Holtek HT66F2740 User manual

12V High Current Flash MCU
HT66F2740
Revision: V1.20 Date: November 20, 2019

Rev. 1.20 2 November 20, 2019 Rev. 1.20 3 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Table of Contents
Features................................................................................................................. 7
CPU Features ...............................................................................................................................7
Peripheral Features.......................................................................................................................7
General Description.............................................................................................. 8
Block Diagram....................................................................................................... 8
Pin Assignment..................................................................................................... 9
Pin Description ................................................................................................... 10
Absolute Maximum Ratings............................................................................... 14
D.C. Characteristics............................................................................................ 14
Operating Voltage Characteristics ..............................................................................................14
Standby Current Characteristics .................................................................................................14
Operating Current Characteristics...............................................................................................15
A.C. Characteristics............................................................................................ 15
High Speed Internal Oscillator – HIRC – Frequency Accuracy ................................................... 15
Low Speed Internal Oscillator Characteristics – LIRC ................................................................16
Operating Frequency Characteristic Curves ...............................................................................16
System Start Up Time Characteristics ........................................................................................16
Input/Output Characteristics ............................................................................. 17
Memory Characteristics ..................................................................................... 17
LVR/LVD Electrical Characteristics ................................................................... 18
Internal Reference Voltage Characteristics...................................................... 18
Over Voltage Protection Electrical Characteristics ......................................... 19
High Voltage I/O Electrical Characteristics ...................................................... 19
Voltage Detector Electrical Characteristics .................................................................................19
High Voltage I/O Other Electrical Characteristics........................................................................20
Low Dropout Regulator Electrical Characteristics.......................................... 20
LDO Other Electrical Characteristics ..........................................................................................21
A/D Converter Electrical Characteristics.......................................................... 22
Power-on Reset Characteristics........................................................................ 22
System Architecture........................................................................................... 22
Clocking and Pipelining...............................................................................................................23
Program Counter.........................................................................................................................23
Stack ...........................................................................................................................................24
Arithmetic and Logic Unit – ALU .................................................................................................24
Flash Program Memory...................................................................................... 25
Structure......................................................................................................................................25
Special Vectors ...........................................................................................................................25
Look-up Table..............................................................................................................................26

Rev. 1.20 2 November 20, 2019 Rev. 1.20 3 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Table Program Example..............................................................................................................26
In Circuit Programming – ICP .....................................................................................................27
On-Chip Debug Support – OCDS ...............................................................................................28
Data Memory ....................................................................................................... 29
Structure......................................................................................................................................29
Data Memory Addressing............................................................................................................30
General Purpose Data Memory ..................................................................................................30
Special Purpose Data Memory ...................................................................................................30
Special Function Register Description............................................................. 32
Indirect Addressing Registers – IAR0, IAR1, IAR2 .....................................................................32
Memory Pointers – MP0, MP1L, MP1H, MP2L, MP2H...............................................................32
Accumulator – ACC.....................................................................................................................33
Program Counter Low Register – PCL........................................................................................34
Look-up Table Registers – TBLP, TBHP, TBLH...........................................................................34
Status Register – STATUS ..........................................................................................................34
EEPROM Data Memory....................................................................................... 36
EEPROM Data Memory Structure ..............................................................................................36
EEPROM Registers ....................................................................................................................36
Reading Data from the EEPROM ...............................................................................................37
Writing Data to the EEPROM......................................................................................................38
Write Protection...........................................................................................................................38
EEPROM Interrupt ......................................................................................................................38
Programming Considerations......................................................................................................38
Oscillators ........................................................................................................... 40
Oscillator Overview .....................................................................................................................40
System Clock Congurations......................................................................................................40
Internal High Speed RC Oscillator – HIRC .................................................................................41
Internal 32kHz Oscillator – LIRC ................................................................................................41
Operating Modes and System Clocks .............................................................. 41
System Clocks ............................................................................................................................41
System Operation Modes............................................................................................................42
Control Registers ........................................................................................................................43
Operating Mode Switching ..........................................................................................................45
Standby Current Considerations .................................................................................................48
Wake-up......................................................................................................................................48
Watchdog Timer.................................................................................................. 49
Watchdog Timer Clock Source....................................................................................................49
Watchdog Timer Control Register ...............................................................................................49
Watchdog Timer Operation .........................................................................................................50
Reset and Initialisation....................................................................................... 51
Reset Functions ..........................................................................................................................51
Reset Initial Conditions ...............................................................................................................53

Rev. 1.20 4 November 20, 2019 Rev. 1.20 5 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Input/Output Ports .............................................................................................. 57
Pull-high Resistors ......................................................................................................................57
Port A Wake-up ...........................................................................................................................58
I/O Port Control Registers ...........................................................................................................58
I/O Port Source Current Control..................................................................................................58
Pin-shared Functions ..................................................................................................................59
I/O Pin Structures........................................................................................................................65
Programming Considerations......................................................................................................65
Timer Modules – TM ........................................................................................... 66
Introduction .................................................................................................................................66
TM Operation ..............................................................................................................................66
TM Clock Source.........................................................................................................................66
TM Interrupts...............................................................................................................................67
TM External Pins.........................................................................................................................67
Programming Considerations......................................................................................................68
Compact Type TM – CTM ................................................................................... 69
Compact Type TM Operation ......................................................................................................69
Compact Type TM Register Description......................................................................................70
Compact Type TM Operating Modes ..........................................................................................74
Standard Type TM – STM ................................................................................... 80
Standard Type TM Operation......................................................................................................80
Standard Type TM Register Description .....................................................................................80
Standard Type TM Operation Modes ..........................................................................................85
Periodic Type TM – PTM..................................................................................... 95
Periodic Type TM Operation........................................................................................................95
Periodic Type TM Register Description .......................................................................................95
Periodic Type TM Operation Modes..........................................................................................100
Over Voltage Protection – OVP........................................................................ 109
Over Voltage Protection Registers ............................................................................................109
Input O󰀨set Calibration ............................................................................................................. 111
Low Dropout Regulator – LDO ........................................................................ 112
High Voltage I/O Ports ...................................................................................... 112
High Voltage I/O Registers............................................................................... 114
Voltage Detector........................................................................................................................ 117
Short-circuit Protection Function ............................................................................................... 118
Universal Serial Interface Module – USIM ...................................................... 119
SPI Interface ............................................................................................................................. 119
I2C Interface ..............................................................................................................................127
UART Interface..........................................................................................................................137
Analog to Digital Converter ............................................................................ 152
A/D Converter Overview ...........................................................................................................152
A/D Converter Register Description ..........................................................................................153

Rev. 1.20 4 November 20, 2019 Rev. 1.20 5 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
A/D Converter Reference Voltage.............................................................................................155
A/D Converter Input Signals......................................................................................................156
A/D Converter Operation...........................................................................................................156
Conversion Rate and Timing Diagram ......................................................................................157
Summary of A/D Conversion Steps ..........................................................................................158
Programming Considerations....................................................................................................159
A/D Conversion Function ..........................................................................................................159
A/D Conversion Programming Examples..................................................................................160
Low Voltage Detector – LVD ............................................................................ 161
LVD Register .............................................................................................................................161
LVD Operation...........................................................................................................................162
Interrupts ........................................................................................................... 163
Interrupt Registers.....................................................................................................................163
Interrupt Operation ....................................................................................................................167
External Interrupts.....................................................................................................................168
Over Voltage Protection Interrupt..............................................................................................169
USIM Interrupt...........................................................................................................................169
Standard and Periodic Type TM Interrupts................................................................................169
LVD Interrupt .............................................................................................................................170
A/D Converter Interrupt .............................................................................................................170
EEPROM Interrupt ....................................................................................................................170
Time Base Interrupts.................................................................................................................170
High Voltage Short Circuit Interrupt...........................................................................................172
Multi-function Interrupt ..............................................................................................................172
Compact Type TM Interrupts.....................................................................................................172
Interrupt Wake-up Function.......................................................................................................173
Programming Considerations....................................................................................................173
Conguration Options...................................................................................... 174
Application Circuits.......................................................................................... 174
Instruction Set................................................................................................... 175
Introduction ...............................................................................................................................175
Instruction Timing ......................................................................................................................175
Moving and Transferring Data...................................................................................................175
Arithmetic Operations................................................................................................................175
Logical and Rotate Operation ...................................................................................................176
Branches and Control Transfer .................................................................................................176
Bit Operations ...........................................................................................................................176
Table Read Operations .............................................................................................................176
Other Operations.......................................................................................................................176
Instruction Set Summary ................................................................................. 177
Table Conventions.....................................................................................................................177
Extended Instruction Set ...........................................................................................................179

Rev. 1.20 6 November 20, 2019 Rev. 1.20 7 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Instruction Denition........................................................................................ 181
Extended Instruction Denition .................................................................................................190
Package Information ........................................................................................ 197
16-pin NSOP-EP (150mil) Outline Dimensions.........................................................................198
24-pin SSOP-EP (150mil) Outline Dimensions .........................................................................199
24-pin SOP (300mil) Outline Dimensions .................................................................................200
28-pin SOP (300mil) Outline Dimensions .................................................................................201

Rev. 1.20 6 November 20, 2019 Rev. 1.20 7 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Features
CPU Features
• Operating voltage
♦fSYS=8MHz: 4.5V~5.5V
♦fSYS=12MHz: 4.5V~5.5V
♦fSYS=16MHz: 4.5V~5.5V
• Up to 0.25μs instruction cycle with 16MHz system clock at VDD=5V
• Power down and wake-up functions to reduce power consumption
• Oscillator types
♦Internal High Speed 8/12/16MHz RC – HIRC
♦Internal Low Speed 32kHz RC – LIRC
• Multi-mode operation: FAST, SLOW, IDLE and SLEEP
• Fully integrated internal oscillators require no external components
• All instructions executed in 1~3 instruction cycles
• Table read instructions
• 115 powerful instructions
• 8-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Flash Program Memory: 4K×16
• RAM Data Memory: 256×8
• True EEPROM Memory: 128×8
• Watchdog Timer function
• Up to 14 bidirectional I/O lines
• 10 bidirectional High Voltage I/O lines with short-circuit protection function
• 2 pin-shared external interrupts
• Multiple Timer Modules for time measurement, capture input, compare match output or PWM
output or single pulse output function
• Over Voltage Protection function with interrupt
• Universal Serial Interface Module – USIM for SPI, I2C or UART communication
• Programmable I/O port source current for LED driving applications
• Dual Time-Base functions for generation of xed time interrupt signals
• 8 external channel 12-bit resolution A/D Converter with Internal Reference Voltage VBG
• Internal 5V LDO
• Low voltage reset function
• Low voltage detect function
• Package types: 16-pin NSOP-EP, 24/28-pin SOP, 24-pin SSOP-EP

Rev. 1.20 8 November 20, 2019 Rev. 1.20 9 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
General Description
The device is a Flash Memory A/D type 8-bit high performance RISC architecture microcontroller
with 12V high current driver. Oering users the convenience of Flash Memory multi-programming
features, this device also includes a wide range of functions and features. Other memory includes an
area of RAM Data Memory as well as an area of true EEPROM memory for storage of non-volatile
data such as serial numbers, calibration data etc.
Analog features include a multi-channel 12-bit A/D Converter and an internal 5V LDO (Low
Dropout Regulator) for voltage regulator. Multiple and extremely exible Timer Modules provide
timing, pulse generation and PWM generation functions. Communication with the outside world
is catered for by including fully integrated SPI, I2C and UART interface functions, these popular
interfaces which provide designers with a means of easy communication with external peripheral
hardware. Protective features such as an internal Watchdog Timer, Low Voltage Reset and Low
Voltage Detector coupled with excellent noise immunity and ESD protection ensure that reliable
operation is maintained in hostile electrical environments.
The device also includes fully integrated high and low speed oscillators which require no external
components for their implementation. The ability to operate and switch dynamically between a range
of operating modes using dierent clock sources gives users the ability to optimise microcontroller
operation and minimise power consumption.
This device contains a programmable I/O port source current function which is used to implement
LED driving function. The High Voltage I/O function specic to 12V high current applications is
also fully integrated within the device. The inclusion of exible I/O programming features, Time-
Base functions, Over Voltage Protection function along with many other features ensure that the
device will nd excellent use in home applications such as Kitchen Ventilators in addition to many
others.
Block Diagram
Interrupt
Controller
12-bit
ADC
Bus
MUX
V
DD
Reset
Circuit
Port A
Driver
VDD
HIRC
8/12/16MHz
LIRC
32kHz
MUX
VSS
VCC1
Timers Pin-Shared
Function
5V LDO
HVIO
INT0~INT1
AN0~AN7
Pin-Shared
With Port A & D
Pin-Shared
With Port A
Port D
Driver
PA0~PA7
PD0~PD5
VCC2
PB0~PB7
PC0~PC1
VREF
Clock System
Time
Bases
HT8 MCU Core
Analog Peripherals
SYSCLK
Digital Peripherals
Pin-Shared
With Port B&C
PTP/STP/CTP
Pin-Shared
With Port A
1.04V
V
CC1O
V
CC2O
Port B
Driver
Port C
Driver
Analog to Digital
Converter
I/O
Pin-Shared
Function
USIM
Comparator
V
DD
+
_
OVPI0
OVPI1
Pin-Shared
With Port A
*：USIM including SPI,I
2
C,UART：Pin- Shared Node
8-bit
DAC
ROM
4K × 16
EEPROM
128 × 8
Watchdog
Timer
RAM
256 × 8
Stack
8-level
LVD/LVR
*
High Voltage
Analog Peripherals

Rev. 1.20 8 November 20, 2019 Rev. 1.20 9 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Pin Assignment
HT66F2740/HT66V2740
16 NSOP-EP-A
VCC2
PB5/CTPPB3
PB4
PB1
PB2
PB0
PA3/INT1/PTPI/SCS/OVPI1/AN1
PA1/INT0/STPI/SCK/SCL/OVPI0/AN0
AVSS/VSS/HVSS PA2/SDI/SDA/RX/ICPCK/OCDSCK
PA0/SDO/TX/SCK/SCL/ICPDA/OCDSDA
PC1/PTP
PC0/STP
AVDD/VDD/VLDO
VCC1
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
HT66F2740/HT66V2740
24 SOP-A/SSOP-EP-A
VCC2
PB7
PB6
PB5/CTP
PB3
PB4
PB1
PB2
PB0
PA3/INT1/PTPI/SCS/OVPI1/AN1
PD0/STPI/SCS/AN2
PA6/INT1/SDI/SDA/RX/STP/AN6
PA7/PTPI/SDO/TX/PTP/AN7
PA1/INT0/STPI/SCK/SCL/OVPI0/AN0
PA4/CTCK/STCK/PTCK/SDI/SDA/RX/VREF/AN4
PA2/SDI/SDA/RX/ICPCK/OCDSCK
PA0/SDO/TX/SCK/SCL/ICPDA/OCDSDA
PD1/STCK/PTCK/SDO/TX/AN3
PC1/PTP
PC0/STP
VCC1
PA5/INT0/SCK/SCL/STPB/AN5
24
23
22
21
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
9
10
11
12
AVDD/VDD/VLDO
AVSS/VSS/HVSS
28
27
26
25
24
23
22
21
20
19
18
17
16
15
1
2
3
4
5
6
7
8
9
10
11
12
13
14
VCC2
PB3
PB4
PB0
PB2
PB1
PA3/INT1/PTPI/SCS/OVPI1/AN1
PD0/STPI/SCS/AN2
PA6/INT1/SDI/SDA/RX/STP/AN6
PA7/PTPI/SDO/TX/PTP/AN7
PA1/INT0/STPI/SCK/SCL/OVPI0/AN0
PD1/STCK/PTCK/SDO/TX/AN3
PB7
PB6
PB5/CTP
PA4/CTCK/STCK/PTCK/SDI/SDA/RX/VREF/AN4
PA2/SDI/SDA/RX/ICPCK/OCDSCK
PA0/SDO/TX/SCK/SCL/ICPDA/OCDSDA
PC1/PTP
PC0/STP
VCC1
PA5/INT0/SCK/SCL/STPB/AN5
AVDD/VDD/VLDO
AVSS/VSS/HVSS
PD4/CTPB/PTPB
PD5/OVPCOUT/PTP
PD3/CTCK/OVPINT
PD2/CTP
HT66F2740/HT66V2740
28 SOP-A
Note: 1. If the pin-shared pin functions have multiple outputs, the desired pin-shared function is determined by the
corresponding software control bits.
2. The OCDSDA and OCDSCK pins are supplied as OCDS dedicated pins and as such only available for
the HT66V2740 device which is the OCDS EV chip for the HT66F2740 device.
3. For less pin-count package types there will be unbonded pins which should be properly congured to
avoid unwanted current consumption resulting from floating input conditions. Refer to the “Standby
Current Considerations” and “Input/Output Ports” sections.
4. The backside plate of EP shall be well soldered to ground on PCB.

Rev. 1.20 10 November 20, 2019 Rev. 1.20 11 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Pin Description
With the exception of the power pins and some relevant transformer control pins, all pins on the
device can be referenced by their Port name, e.g. PA0, PA1 etc., which refer to the digital I/O
function of the pins. However these Port pins are also shared with other function such as the Analog
to Digital Converter, Timer Module pins etc. The function of each pin is listed in the following table,
however the details behind how each pin is congured is contained in other sections of the datasheet.
Note that the pin description refers to the largest package size, as a result some pins may not exist on
smaller package types.
Pin Name Function OPT I/T O/T Description
PA0/SDO/TX/
SCK/SCL/ICPDA/
OCDSDA
PA0
PAPU
PAWU
PAS0
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
SDO PAS0 — CMOS SPI serial data output
TX PAS0 — CMOS UART data transmitter pin
SCK PAS0
IFS0 ST CMOS SPI serial clock
SCL PAS0
IFS0 ST NMOS I2C clock line
ICPDA — ST CMOS ICP address/data
OCDSDA — ST CMOS OCDS address/data, for EV chip only
PA1/INT0/STPI/
SCK/SCL/OVPI0/
AN0
PA1
PAPU
PAWU
PAS0
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
INT0 PAS0
IFS1 ST — External Interrupt 0 input
STPI PAS0
IFS1 ST — STM capture input
SCK PAS0
IFS0 ST CMOS SPI serial clock
SCL PAS0
IFS0 ST NMOS I2C clock line
OVPI0 PAS0 AN — OVP signal input
AN0 PAS0 AN — A/D Converter external input channel 0
PA2/SDI/SDA/RX/
ICPCK/OCDSCK
PA2
PAPU
PAWU
PAS0
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
SDI PAS0
IFS0 ST — SPI serial data input
SDA PAS0
IFS0 ST NMOS I2C data line
RX PAS0
IFS0 ST — UART data receiver pin
ICPCK — ST — ICP clock pin
OCDSCK — ST — OCDS clock pin, for EV chip only

Rev. 1.20 10 November 20, 2019 Rev. 1.20 11 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Pin Name Function OPT I/T O/T Description
PA3/INT1/PTPI/
SCS/OVPI1/AN1
PA3
PAPU
PAWU
PAS0
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
INT1 PAS0
IFS1 ST — External Interrupt 1 input
PTPI PAS0
IFS2 ST — PTM capture input
SCS PAS0
IFS0 ST CMOS SPI slave select
OVPI1 PAS0 AN — OVP signal input
AN1 PAS0 AN — A/D Converter external input channel 1
PA4/CTCK/STCK/
PTCK/SDI/SDA/
RX/VREF/AN4
PA4
PAPU
PAWU
PAS1
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
CTCK PAS1
IFS2 ST — CTM clock input
STCK PAS1
IFS1 ST — STM clock input
PTCK PAS1
IFS0 ST — PTM clock input
SDI PAS1
IFS0 ST — SPI serial data input
SDA PAS1
IFS0 ST NMOS I2C data line
RX PAS1
IFS0 ST — UART data receiver pin
VREF PAS1 AN — A/D Converter external reference input
AN4 PAS1 AN — A/D Converter external input channel 4
PA5/INT0/SCK/
SCL/STPB/AN5
PA5
PAPU
PAWU
PAS1
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
INT0 PAS1
IFS1 ST — External Interrupt 0 input
SCK PAS1
IFS0 ST CMOS SPI serial clock
SCL PAS1
IFS0 ST NMOS I2C clock line
STPB PAS1 — CMOS STM inverting output
AN5 PAS1 AN — A/D Converter external input channel 5
PA6/INT1/SDI/
SDA/RX/STP/AN6
PA6
PAPU
PAWU
PAS1
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
INT1 PAS1
IFS1 ST — External Interrupt 1 input
SDI PAS1
IFS0 ST — SPI serial data input
SDA PAS1
IFS0 ST NMOS I2C data line
RX PAS1
IFS0 ST — UART data receiver pin
STP PAS1 — CMOS STM output
AN6 PAS1 AN — A/D Converter external input channel 6

Rev. 1.20 12 November 20, 2019 Rev. 1.20 13 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Pin Name Function OPT I/T O/T Description
PA7/PTPI/SDO/
TX/PTP/AN7
PA7
PAPU
PAWU
PAS1
ST CMOS General purpose I/O. Register enabled pull-up and wake-up
PTPI PAS1
IFS2 ST — PTM capture input
SDO PAS1 — CMOS SPI serial data output
TX PAS1 — CMOS UART data transmitter pin
PTP PAS1 — CMOS PTM output
AN7 PAS1 AN — A/D Converter external input channel 7
PB0~PB4 PB0~PB4 — ST CMOS High voltage I/O
PB5/CTP PB5 PBS1 ST CMOS High voltage I/O
CTP PBS1 — CMOS High voltage CTM output
PB6~PB7 PB6~PB7 — ST CMOS High voltage I/O
PC0/STP PC0 PCS0 ST CMOS High voltage I/O
STP PCS0 — CMOS High voltage STM output
PC1/PTP PC1 PCS0 ST CMOS High voltage I/O
PTP PCS0 — CMOS High voltage PTM output
PD0/STPI/SCS/
AN2
PD0 PDPU
PDS0 ST CMOS General purpose I/O. Register enabled pull-up
STPI PDS0
IFS1 ST — STM capture input
SCS PDS0
IFS0 ST CMOS SPI slave select
AN2 PDS0 AN — A/D Converter external input channel 2
PD1/STCK/PTCK/
SDO/TX/AN3
PD1 PDPU
PDS0 ST CMOS General purpose I/O. Register enabled pull-up
STCK PDS0
IFS1 ST — STM clock input
PTCK PDS0
IFS0 ST — PTM clock input
SDO PDS0 — CMOS SPI serial data output
TX PDS0 — CMOS UART data transmitter pin
AN3 PDS0 AN — A/D Converter external input channel 3
PD2/CTP PD2 PDPU
PDS0 ST CMOS General purpose I/O. Register enabled pull-up
CTP PDS0 — CMOS CTM output
PD3/CTCK/
OVPINT
PD3 PDPU
PDS0 ST CMOS General purpose I/O. Register enabled pull-up
CTCK PDS0
IFS2 ST — CTM clock input
OVPINT PDS0 — CMOS OVP comparator output (after debounce)
PD4/CTPB/PTPB
PD4 PDPU
PDS1 ST CMOS General purpose I/O. Register enabled pull-up
CTPB PDS1 — CMOS CTM inverting output
PTPB PDS1 — CMOS PTM inverting output
PD5/OVPCOUT/
PTP
PD5 PDPU
PDS1 ST CMOS General purpose I/O. Register enabled pull-up
OVPCOUT PDS1 — CMOS OVP comparator output (before debounce)
PTP PDS1 — CMOS PTM output

Rev. 1.20 12 November 20, 2019 Rev. 1.20 13 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Pin Name Function OPT I/T O/T Description
VDD/AVDD/VLDO
VDD — PWR — Digital positive power supply
AVDD — PWR — A/D Converter positive power supply
VLDO — PWR — LDO output voltage
VSS/AVSS/HVSS
VSS — PWR — Digital negative power supply
AVSS — PWR — A/D Converter negative power supply
HVSS — PWR — High Voltage Power negative power supply
VCC1 VCC1 — PWR — High Voltage Power for LDO input voltage
VCC2 VCC2 — PWR — High Voltage Power for HVIO & Level Shifter input voltage
Legend: I/T: Input type; O/T: Output type;
OPT: Optional by register option; PWR: Power;
ST: Schmitt Trigger input; CMOS: CMOS output;
NMOS: NMOS output; AN: Analog signal.

Rev. 1.20 14 November 20, 2019 Rev. 1.20 15 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Absolute Maximum Ratings
Supply Voltage (VCC1, VCC2).....................................................................................VSS-0.3V to 15.0V
Supply Voltage (VDD).................................................................................................VSS-0.3V to 6.0V
High Voltage Input Voltage .............................................................................. VSS-0.3V to VCC2+0.3V
Input Voltage ..................................................................................................... VSS-0.3V to VDD+0.3V
Storage Temperature..................................................................................................... -50°C to 125°C
Operating Temperature................................................................................................... -40°C to 85°C
High Voltage IOH Total.............................................................................................................. -150mA
IOH Total...................................................................................................................................... -80mA
High Voltage IOL Total ............................................................................................................... 150mA
IOL Total ....................................................................................................................................... 80mA
Total Power Dissipation ........................................................................................................... 500mW
Note: These are stress ratings only. Stresses exceeding the range specified under “Absolute
Maximum Ratings” may cause substantial damage to the device. Functional operation of the
device at other conditions beyond those listed in the specication is not implied and prolonged
exposure to extreme conditions may aect device reliability.
D.C. Characteristics
For data in the following tables, note that factors such as oscillator type, operating voltage, operating
frequency, pin load conditions, temperature and program instruction type, etc., can all exert an
inuence on the measured values.
Operating Voltage Characteristics
Ta=-40°C~85°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD
Operating Voltage – HIRC
fHIRC=8MHz 4.5 — 5.5
VfHIRC=12MHz 4.5 — 5.5
fHIRC=16MHz 4.5 — 5.5
Operating Voltage – LIRC fLIRC=32kHz 4.5 — 5.5 V
Standby Current Characteristics
Ta=25°C
Symbol Standby Mode Test Conditions Min. Typ. Max. Unit
VDD Conditions
ISTB
SLEEP Mode 5V WDT o󰀨 — 0.5 1.0 μA
WDT on — 3.0 5.0 μA
IDLE0 Mode – LIRC 5V fSUB on — 5.0 10.0 μA
IDLE1 Mode – HIRC 5V
fSUB on, fSYS=8MHz — 0.6 0.8
mAfSUB on, fSYS=12MHz — 0.8 1.2
fSUB on, fSYS=16MHz — 1.4 2.0
Note: When using the characteristic table data, the following notes should be taken into consideration:
1. Any digital inputs are setup in a non-oating condition.
2. All measurements are taken under conditions of no load and with all peripherals in an o state.
3. There are no DC current paths.

Rev. 1.20 14 November 20, 2019 Rev. 1.20 15 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
4. All Standby Current values are taken after a HALT instruction execution thus stopping all instruction
execution.
5. The above current does not contain the current in the high voltage circuit, so the current consumption in
the high voltage circuit should be added when the device is operating.
Operating Current Characteristics
Ta=25°C
Symbol Operating Mode Test Conditions Min. Typ. Max. Unit
VDD Conditions
IDD
SLOW Mode – LIRC 5V fSYS=32kHz — 30 50 μA
FAST Mode – HIRC 5V
fSYS=8MHz — 1.6 2.4
mAfSYS=12MHz — 2.4 3.6
fSYS=16MHz — 3.2 4.8
Note: When using the characteristic table data, the following notes should be taken into consideration:
1. Any digital inputs are setup in a non-oating condition.
2. All measurements are taken under conditions of no load and with all peripherals in an o state.
3. There are no DC current paths.
4. All Operating Current values are measured using a continuous NOP instruction program loop.
5. The above current does not contain the current in the high voltage circuit, so the current consumption in
the high voltage circuit should be added when the device is operating.
A.C. Characteristics
For data in the following tables, note that factors such as oscillator type, operating voltage, operating
frequency and temperature etc., can all exert an inuence on the measured values.
High Speed Internal Oscillator – HIRC – Frequency Accuracy
During the program writing operation the writer will trim the HIRC oscillator at a user selected
HIRC frequency and user selected voltage of 5V.
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Temp.
fHIRC
8MHz Writer Trimmed HIRC Frequency
5V 25°C -1% 8 +1%
MHz
-40°C~85°C -2% 8 +2%
4.5V~5.5V 25°C -2.5% 8 +2.5%
-40°C~85°C -3% 8 +3%
12MHz Writer Trimmed HIRC Frequency
5V 25°C -1% 12 +1%
MHz
-40°C~85°C -2% 12 +2%
4.5V~5.5V 25°C -2.5% 12 +2.5%
-40°C~85°C -3% 12 +3%
16MHz Writer Trimmed HIRC Frequency
5V 25°C -1% 16 +1%
MHz
-40°C~85°C -2% 16 +2%
4.5V~5.5V 25°C -2.5% 16 +2.5%
-40°C~85°C -3% 16 +3%
Note: 1. The 5V values for VDD are provided as these are the fixed voltage at which the HIRC frequency is
trimmed by the writer.
2. The row below the 5V trim voltage row is provided to show the values for the full VDD range operating
voltage. It is recommended that the trim voltage is xed at 5V for application voltage ranges from 4.5V
to 5.5V.

Rev. 1.20 16 November 20, 2019 Rev. 1.20 17 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
3. The minimum and maximum tolerance values provided in the table are only for the frequency at which
the writer trims the HIRC oscillator. After trimming at this chosen specific frequency any change in
HIRC oscillator frequency using the oscillator register control bits by the application program will give a
frequency tolerance to within ±20%.
Low Speed Internal Oscillator Characteristics – LIRC
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Temp.
fLIRC LIRC Frequency 4.5V~5.5V 25°C -10% 32 +10% kHz
-40°C~85°C -50% 32 +60%
tSTART LIRC Start Up Time — — — — 500 μs
Operating Frequency Characteristic Curves
System Operating Frequency
Operating Voltage
8MHz
12MHz
16MHz
~ ~
4.5V 5.5V
~
~
~ ~
System Start Up Time Characteristics
Ta=25°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
tSST
System Start-up Time
Wake-up from Condition where fSYS is O󰀨
— fSYS=fH~fH/64, fH=fHIRC — 16 — tSYS
— fSYS=fSUB=fLIRC — 2 — tSYS
System Start-up Time
Wake-up from Condition where fSYS is On
— fSYS=fH~fH/64, fH=fHIRC — 2 — tSYS
— fSYS=fSUB=fLIRC — 2 — tSYS
System Speed Switch Time
FAST to SLOW Mode or SLOW to FAST Mode
— fHIRC switches from o󰀨 →on — 16 — tHIRC
tRSTD
System Reset Delay Time
Reset Source from Power-on Reset or
LVR Hardware Reset
— RRPOR=5V/ms
25 50 100 ms
System Reset Delay Time
LVRC/WDTC Software Reset — —
System Reset Delay Time
Reset Source from WDT Overow — — 8.3 16.7 33.3 ms
tSRESET Minimum Software Reset Width to Reset — — 45 90 120 μs
Note: 1. For the System Start-up time values, whether fSYS is on or o depends upon the mode type and the chosen
fSYS system oscillator. Details are provided in the System Operating Modes section.
2. The time units, shown by the symbols tHIRC, tSYS etc. are the inverse of the corresponding frequency
values as provided in the frequency tables. For example tHIRC=1/fHIRC, tSYS=1/fSYS etc.

Rev. 1.20 16 November 20, 2019 Rev. 1.20 17 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
3. If the LIRC is used as the system clock and if it is o when in the SLEEP Mode, then an additional
LIRC start up time, tSTART, as provided in the LIRC frequency table, must be added to the tSST time in the
table above.
4. The System Speed Switch Time is eectively the time taken for the newly activated oscillator to start up.
Input/Output Characteristics
Ta=25°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VIL Input Low Voltage for I/O Ports or Input Pins 5V —0 — 1.5 V
— 0 — 0.2VDD
VIH Input High Voltage for I/O Ports or Input Pins 5V —3.5 — 5.0 V
— 0.8VDD — VDD
IOL
Sink Current for I/O Pins
(PA0~PA7 and PD0~PD5 pins) 5V VOL=0.1VDD 32 65 — mA
IOH
Source Current for I/O Pins
(PA0~PA7 and PD0~PD5 pins) 5V
VOH=0.9VDD
SLEDC[m+1:m]=00B
(m=0, 2, 4, 6)
-1.5 -2.9 —
mA
VOH=0.9VDD
SLEDC[m+1:m]=01B
(m=0, 2, 4, 6)
-2.5 -5.1 —
VOH=0.9VDD
SLEDC[m+1:m]=10B
(m=0, 2, 4, 6)
-3.6 -7.3 —
VOH=0.9VDD
SLEDC[m+1:m]=11B
(m=0, 2, 4, 6)
-8 -16 —
RPH Pull-high Resistance for I/O Ports (Note) 5V — 10 30 50 kΩ
ILEAK Input Leakage Current 5V VIN=VDD or VIN=VSS — — ±1 μA
tTCK TM TCK Input Pin Minimum Pulse Width — — 0.3 — — μs
tTPI TM TPI Input Pin Minimum Pulse Width — — 0.3 — — μs
tINT External Interrupt Minimum Pulse Width — — 10 — — μs
Note: The RPH internal pull high resistance value is calculated by connecting to ground and enabling input pin with
a pull-high resistor and then measuring the pin current at the specied supply voltage level. Dividing the
voltage by this measured current provides the RPH value.
Memory Characteristics
Ta=-40°C~85°C, unless otherwise specied
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VRW VDD for Read / Write — — VDDmin — VDDmax V
Flash Program / Data EEPROM Memory
tDEW Write Cycle Time – Data EEPROM Memory — — — 4 8 ms
EP
Cell Endurance – Flash Program Memory — — 10K — — E/W
Cell Endurance – Data EEPROM Memory — — 100K — — E/W
tRETD ROM Data Retention Time — Ta=25°C — 40 — Year
RAM Data Memory
VDR RAM Data Retention Voltage — Device in SLEEP Mode 1.0 — — V

Rev. 1.20 18 November 20, 2019 Rev. 1.20 19 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
LVR/LVD Electrical Characteristics
Ta=25°C, unless otherwise specied
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VLVR Low Voltage Reset Voltage —
LVR enable, voltage select 2.1V
Ta=-40°C~85°C
-5%
2.1
+5% V
LVR enable, voltage select 2.55V
Ta=-40°C~85°C 2.55
LVR enable, voltage select 3.15V
Ta=-40°C~85°C 3.15
LVR enable, voltage select 3.8V
Ta=-40°C~85°C 3.8
VLVD Low Voltage Detection Voltage —
LVD enable, voltage select 2.0V
Ta=-40°C~85°C
-5%
2.0
+5% V
LVD enable, voltage select 2.2V
Ta=-40°C~85°C 2.2
LVD enable, voltage select 2.4V
Ta=-40°C~85°C 2.4
LVD enable, voltage select 2.7V
Ta=-40°C~85°C 2.7
LVD enable, voltage select 3.0V
Ta=-40°C~85°C 3.0
LVD enable, voltage select 3.3V
Ta=-40°C~85°C 3.3
LVD enable, voltage select 3.6V
Ta=-40°C~85°C 3.6
LVD enable, voltage select 4.0V
Ta=-40°C~85°C 4.0
ILVRLVDBG Operating Current 5V LVD enable, LVR enable, VBGEN=0 — 20 25 μA
LVD enable, LVR enable, VBGEN=1 — 180 200 μA
tLVDS LVDO Stable Time —
For LVR enable, VBGEN=0,
LVD o󰀨 → on
Ta=-40°C~85°C
— — 18 μs
tLVR
Minimum Low Voltage Width to
Reset — — 120 240 480 μs
tLVD
Minimum Low Voltage Width to
Interrupt — — 60 120 240 μs
Internal Reference Voltage Characteristics
Ta=25°C, unless otherwise specied
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VBG Bandgap Reference Voltage — Ta=-40°C~85°C -5% 1.04 +5% V
tBGS VBG Turn On Stable Time — No load — — 150 μs
Note: 1. All the above parameters are measured under conditions of no load condition unless otherwise described.
2. A 0.1μF ceramic capacitor should be connected between VDD and GND.
3. The VBG voltage is used as the A/D Converter internal signal input.

Rev. 1.20 18 November 20, 2019 Rev. 1.20 19 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
Over Voltage Protection Electrical Characteristics
Ta=25°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
IOVP Operating Current 5V OVPEN=1, DAC VREF=VDD — 500 750 μA
VOS Input O󰀨set Voltage 5V With calibration -2 — 2 mV
VHYS Hysteresis
5V HYS[1:0]=00B 0 0 5 mV
5V HYS[1:0]=01B 15 30 45 mV
5V HYS[1:0]=10B 40 60 80 mV
5V HYS[1:0]=11B 60 80 100 mV
VCM Common Mode Voltage Range 5V — VSS — VDD - 1 V
DNL Di󰀨erential Non-linearity 5V DAC VREF=VDD — — ±1 LSB
INL Integral Non-linearity 5V DAC VREF=VDD — — ±1.5 LSB
High Voltage I/O Electrical Characteristics
VDD=5V, Ta=25°C, unless otherwise specify
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VIN Input Voltage — — 7.5 — 12.0 V
VIH Input High Voltage for High Voltage I/O Ports — — 0.7VIN — VIN V
VIL Input Low Voltage for High Voltage I/O Ports — — 0 — 0.3VIN V
IOH Source Current for High Voltage I/O Ports — VOH=0.9×VIN, VIN=12V -60 -120 — mA
IOL Sink Current for High Voltage I/O Ports — VOL=0.1×VIN, VIN=12V 60 120 — mA
tSF Short Flag Response Time
— VIN≥7.5V, SFRTC=0 0.9 — 1.7 ms
—VIN≥7.5V, SFRTC=0,
Ta=-40°C~85°C 0.6 — 3.0 ms
— VIN≥7.5V, SFRTC=1 0.45 — 1.10 ms
—VIN≥7.5V, SFRTC=1,
Ta=-40°C~85°C 0.3 — 1.5 ms
Voltage Detector Electrical Characteristics
Ta=25°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VIN VCC2 Input Voltage — — 7.5 — 12 V
VDET1 VCC2 Detect Level — VIN=0V → 12V 6.5 7.0 7.5 V
VDET2 VDD Detect Level — VDD=0V → 5V 2.8 3.0 3.2 V
IQQuiescent Current(Note) — No load, VIN=12V, VDD=5V — 20 40 μA
Note: When measuring the Quiescent Current IQ, the VCC2O signal cannot be selected for A/D Converter input.
Because if the VCC2O is selected, CWSEL is 0, it will enable the resistance divider circuit to form load,
resulting in wrong measurement result.

Rev. 1.20 20 November 20, 2019 Rev. 1.20 21 November 20, 2019
HT66F2740
12V High Current Flash MCU
HT66F2740
12V High Current Flash MCU
High Voltage I/O Other Electrical Characteristics
Ta=25°C
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VDD Conditions
VIN Input Voltage — — 7.5 — 12.0 V
VCC2O VCC2O Accuracy — VIN=12V -5% 0.2VIN +5% V
Low Dropout Regulator Electrical Characteristics
CLOAD=10μF+0.1μF, VIN=VOUT+1V, Ta=25°C, unless otherwise specied
Symbol Parameter Test Conditions Min. Typ. Max. Unit
VIN Conditions
VIN Input Voltage — — VOUT+0.1 6 12 V
VOUT Output Voltage
— ILOAD=1mA, VOUT=5.0V -2% 5.0 2% V
—Ta=-40°C~85°C,
ILOAD=1mA, VOUT=5.0V -5% 5.0 5% V
ΔVLOAD Load Regulation (1) —1mA≤ILOAD≤250mA, — 0.02 0.05 %/mA
VDROP Dropout Voltage (2)
—ΔVOUT=2%, ILOAD=1mA — 20 — mV
—ΔVOUT=2%, ILOAD=10mA — 100 — mV
—VIN=VOUT+1.5V,
ΔVOUT=2%, ILOAD=70mA — 600 1000 mV
IOUT Output Current — ΔVOUT=-3% 250 — — mA
IQQuiescent Current(3) 12V No load — 80 150 μA
ΔVLINE Line Regulation — VOUT+1V≤VIN≤12V, ILOAD=1mA — — 0.5 %/V
TC Temperature Coe󰀩cient — Ta=-40°C~85°C, ILOAD=10mA — ±1.5 ±2 mV/°C
ΔVOUT_RIPPLE Output Voltage Ripple 6V ILOAD=10mA — — 50 mV
RR Ripple Rejection(4) —VIN=10VDC+2VP-P(AC),
ILOAD≤50mA, f=120Hz 35 — — dB
ILIMIT Current Limit 6V ΔVOUT=-10% 700 — — mA
Note: 1. Load regulation is measured at a constant junction temperature, using pulse testing with a low ON time
and is guaranteed up to the maximum power dissipation. Power dissipation is determined by the input/
output dierential voltage and the output current. Guaranteed maximum power dissipation will not be
available over the full input/output range. The maximum allowable power dissipation at any ambient
temperature is PD=(TJ(MAX)-Ta)/θJA
2. Dropout voltage is dened as the input voltage minus the output voltage that produces a 2% change in the
output voltage from the value at appointed VIN.
3. When measuring the Quiescent Current IQ, the VCC1O signal cannot be selected for A/D Converter input.
Because if the VCC1O is selected, CWSEL is 0, it will enable the resistance divider circuit to form load,
resulting in wrong measurement result.
4. Ripple rejection ratio measurement circuit. RR=20×log(ΔVIN/ΔVOUT).
0.33μF
13
2
10μF
RL
Output
GND
LDO
VIN VOUT