ST 32L152CDISCOVERY User manual

October 2023 UM1079 Rev 5 1/38
1
UM1079
User manual
Discovery kit with STM32L152RC MCU
Introduction
The 32L152CDISCOVERY Discovery kit helps the development of applications based on
the STM32L1 series microcontrollers and benefits from the ultra-low-power features of
these devices.
Based on the STM32L152RC microcontroller, this Discovery kit includes an ST-LINK/V2
embedded debugging tool interface, a 24-segment 4-common LCD, LEDs, push-buttons, a
linear touch sensor, and touchkeys.
Figure 1. 32L152CDISCOVERY board
1. Picture is not contractual.
www.st.com

Contents UM1079
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Contents
1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2 Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.1 Codification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.1 System requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2 Development toolchains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.3 Demonstration software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
4 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5 Quick start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5.1 Getting started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
6 Hardware and layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.1 32L152CDISCOVERY top and bottom layouts . . . . . . . . . . . . . . . . . . . . 12
6.2 Mechanical drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
6.3 Embedded ST-LINK/V2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.3.1 Using the ST-LINK/V2 to program/debug the on-board microcontroller 16
6.3.2 Using the ST-LINK/V2 to program/debug an external application . . . . . 17
6.4 Power supply and power selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.5 LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.6 Push-buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.7 Linear touch sensor and touchkeys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.8 Built-in IDD measurement circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.8.1 High IDD range mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.8.2 Low IDD range mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.8.3 IBIAS current measurement procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.9 Solder bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.10 LCD (24 segments, four commons) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
7 Extension connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

UM1079 Rev 5 3/38
UM1079 Contents
3
8 32L152CDISCOVERY product information . . . . . . . . . . . . . . . . . . . . . . 32
8.1 Product marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
8.2 32L152CDISCOVERY product history . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
8.3 Board revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
9 Federal Communications Commission (FCC)
and ISED Canada Compliance Statements . . . . . . . . . . . . . . . . . . . . . . 35
9.1 FCC Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9.1.1 Part 15.19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9.1.2 Part 15.21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9.1.3 Part 15.105 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
9.2 ISED Compliance Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
10 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

List of tables UM1079
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List of tables
Table 1. Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 2. Codification explanation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Table 3. ON/OFF conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 4. Executed functions when clicking the B1 button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 5. Jumper states . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Table 6. SWD debug connector (CN2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Table 7. Solder bridges. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 8. LCD connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 9. MCU pin description versus board function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 10. Product history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Table 11. Board revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 12. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

UM1079 Rev 5 5/38
UM1079 List of figures
5
List of figures
Figure 1. 32L152CDISCOVERY board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2. Hardware block diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 3. Top layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 4. Bottom layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 5. Mechanical drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 6. 32L152CDISCOVERY connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 7. ST-LINK connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 8. IDD measurement circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 9. Low IDD range measurement timing diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 10. LCD segment mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Features UM1079
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1 Features
•STM32L152RC Arm®(a) Cortex®-M3 core-based microcontroller with 256 Kbytes of
flash memory, 32 Kbytes of RAM, and 8 Kbytes of data EEPROM in an LQFP64
package
•24-segment 4-common LCD in a DIP28 package
•Four LEDs:
– LD1 (red/green) for USB communication
– LD2 (red) for 3.3 V power-on
– Two user LEDs, LD3 (green) and LD4 (blue)
•User and reset push-buttons
•One linear touch sensor and four touchkeys
•Board connectors:
– Serial Wire Debug port (SWD)
– Extension header for LQFP64 I/Os for quick connection to prototyping board and
easy probing
•Flexible power supply options: ST-LINK USB VBUS or external sources
•External application power supply: 3 V and 5 V
•IDD current measurement
•Comprehensive free software libraries and examples available with the STM32Cube
MCU Package
•On-board ST-LINK/V2 debugger/programmer with USB re-enumeration capability:
Virtual COM port, and debug port
•Support of a wide choice of Integrated Development Environments (IDEs) including
IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE
•The former STM32L-DISCOVERY Discovery kit offered the same features except for
the STM32L152RB microcontroller with 128 Kbytes of flash memory, 16 Kbytes of
RAM, and 4 Kbytes of data EEPROM, in an LQFP64 package.
a. Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.

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UM1079 Ordering information
37
2 Ordering information
To order the 32L152CDISCOVERY ultra-low-power Discovery kit, refer to Table 1.
2.1 Codification
The meaning of the codification is explained in Table 2.
Table 1. Ordering information
Order code Board reference Target STM32L1
STM32L152C-DISCO(1)
1. Subsequently called main board in the rest of the documentation.
MB963 STM32L152RCT6
STM32L-DISCOVERY(2)
2. STM32L-DISCOVERY is replaced by STM32L152C-DISCO.
STM32L152RBT6
Table 2. Codification explanation
STM32XXYYZ-
DISCO Description Example: STM32L152C- DISCO
STM32XX MCU series in STM32 32-bit Arm Cortex
MCUs STM32L1 series
YY MCU product line in the series STM32L151/152
ZSTM32L1 flash memory size:
-C for 256 Kbytes 256 Kbytes
DISCO Discovery kit Discovery kit

System requirements UM1079
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3 System requirements
3.1 System requirements
•Multi-OS support: Windows®10, Linux®64-bit, or macOS®(a)(b)(c)
•USB Type-A or USB Type-C® to Mini-B cable
3.2 Development toolchains
•IAR Systems®- IAR Embedded Workbench®(d)
•Keil®- MDK-ARM(d)
•STMicroelectronics - STM32CubeIDE
3.3 Demonstration software
The demonstration software, included in the STM32Cube MCU Package corresponding to
the on-board microcontroller, is preloaded in the STM32 flash memory for easy
demonstration of the device peripherals in standalone mode. The latest versions of the
demonstration source code and associated documentation can be downloaded from
www.st.com.
a. macOS®is a trademark of Apple Inc., registered in the U.S. and other countries and regions.
b. Linux®is a registered trademark of Linus Torvalds.
c. Windows is a trademark of the Microsoft group of companies.
d. On Windows®only.

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UM1079 Conventions
37
4 Conventions
Table 3 provides the conventions used for the ON and OFF settings in the present
document.
The following sections of this user manual are also applicable to the STM32L-DISCOVERY
except for specific features of the STM32L152RB microcontroller with 128 Kbytes of flash
memory, 16 Kbytes of RAM, and 4 Kbytes of data EEPROM.
Table 3. ON/OFF conventions
Convention Definition
Jumper JPx ON Jumper fitted
Jumper JPx OFF Jumper not fitted
Jumper JPx [1-2] Jumper fitted between pin 1 and pin 2
Solder bridge SBx ON SBx connections closed by 0 resistor
Solder bridge SBx OFF SBx connections left open
Resistor Rx ON Resistor soldered
Resistor Rx OFF Resistor not soldered
Capacitor Cx ON Capacitor soldered
Capacitor Cx OFF Capacitor not soldered

Quick start UM1079
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5 Quick start
Before using the Discovery kit, accept the evaluation product license agreement available
on the 32L152CDISCOVERY page of the www.st.com/mcu website.
5.1 Getting started
The following sequence configures 32L152CDISCOVERY and launches the Discovery
application:
•Check jumper positions on the board: JP1 and CN3 must be ON (Discovery selected)
(refer to Figure 3).
•Connect the 32L152CDISCOVERY to a computer with a USB cable to power the
board. The red LEDs LD2 (PWR) and LD1 (COM) are lit up. Function 1 is executed.
•Click on the user button (B1) to change the executed function as described in Table 4.
The 4-LED bar shows the performed function (up to four bars can be switched ON).
Depending on the function selected, the voltage value, the linear touch sensor position, the
touchkeys status, or the STM32L152RC, the current consumption is displayed on the LCD.
Refer to the www.st.com/mcu website for more details on the Discovery project and the
STM32L152RC features.
Table 4. Executed functions when clicking the B1 button
Function LED LD3/4 Bar
status Value displayed on LCD Main function
1LD3 and
LD4 blink Measured STM32L152RC VDD voltage Voltage measurement
2 LD3 ON Linear touch sensor position from 0 to 100% Touch sensing
3 LD4 ON Status of the four touchkeys
4
LD3 and
LD4 OFF
STM32L152RC consumption is measured in Run
mode (4 MHz).
STM32L152RC current
consumption
measurement
STM32L152RC consumption is measured in Sleep
mode (4 MHz).
5
STM32L152RC consumption is measured in Run
mode (32 KHz).
STM32L152RC consumption is measured in
Low-power sleep mode (32 KHz).
6
STM32L152RC consumption is measured in Stop
mode, RTC ON.
STM32L152RC consumption is measured in Stop
mode, RTC OFF.
7STM32L152RC consumption is measured in Standby
mode.

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37
6 Hardware and layout
The 32L152CDISCOVERY is designed around one STM32L152RC packaged in an
LQFP64.
Figure 2 illustrates the connections between the STM32L152RC microcontroller and its
peripherals (ST-LINK/V2, push-buttons, LEDs, LCD, linear touch sensor, touchkeys, and
connectors). These connections are the same for the STM32L-DISCOVERY.
Figure 2. Hardware block diagram
Figure 3 and Figure 4 locate these features on the board.
DT19048V1
I/O
USB
Mini-B
Green LED
(LD3)
RESET
(B2)
RESE
T
I/OI/O
Header
Header
SWD
LCD (24 segments, four commons)
IDD
measurement
Embedded
ST-LINK/V2
STM32L152RCT6
Linear touch sensor
and touchkeys
Blue LED
(LD4)
USER
(B1)

Hardware and layout UM1079
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6.1 32L152CDISCOVERY top and bottom layouts
Figure 3. Top layout
1. A square identifies pin1 of the CN1, CN2, P1, and P2 connectors.
MSv19049V4
COM LED
(LD1)
SWD connector
(CN2)
LCD
24 segments
I
DD measurement
(JP1)
ST-LINK/V2
3V power supply
input/output 5V power supply
input/output
STM32L152RCT6
User button
(B1)
Reset button
(B2)
Green LED
(LD3)
Blue LED
(LD4)
PWR LED
(LD2)
IDD module
ST-LINK/DISCOVERY
selector
(CN3)
Linear touch sensor
and touch keys
B1-USER
(SB4) B2-RESET
(SB5)
BOOT0
(SB3)
3V/VBAT selector
(JP2)
(optional not mounted)
IDD measurement
(SB1 and SB2)

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UM1079 Hardware and layout
37
Figure 4. Bottom layout
1. A square identifies pin 1 of the CN1, CN2, P1, and P2 connectors.
MSv19050V2
Reserved
(SB6, SB8, SB10, and SB12)
Default
(SB7, SB9, SB11, and SB13)
Male header
(P2)
I
DD
(JP1)
CR2032 battery holder
(CR1)
(optional)
X3 crystal
(SB18 and SB20)
I
DD
measurement
(SB14)
X2 crystal
(SB15 and SB16)
V
DD
powered from 3V
(SB21)
Battery enable
(SB22)
NRST
(SB100)
SB101
(SWO)
STM_RST
(SB102)
BOOT1
(SB19) MCO
(SB17)
Male header
(P1)

Hardware and layout UM1079
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6.2 Mechanical drawing
Figure 5. Mechanical drawing
MS31848V1
www.st.com/stm32l152c-discovery
MB963 C

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UM1079 Hardware and layout
37
6.3 Embedded ST-LINK/V2
The ST-LINK/V2 programming and debugging tool is integrated into the
32L152CDISCOVERY. The embedded ST-LINK/V2 can be used in two different ways
according to the jumper configuration (refer to Table 5):
•Program/debug the MCU on board
•Program/debug an MCU in an external application board using a cable connected to
the SWD connector (CN2)
The embedded ST-LINK/V2 supports only SWD for STM32 devices. For information about
debugging and programming features, refer to the user manual ST-LINK/V2 in-circuit
debugger/programmer for STM8 and STM32 (UM1075).
Table 5. Jumper states
Jumper state Description
Both CN3 jumpers ON ST-LINK/V2 functions are enabled for on-board programming
(default).
Both CN3 jumpers OFF ST-LINK/V2 functions are enabled for external application
through the CN2 connector (SWD supported).

Hardware and layout UM1079
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6.3.1 Using the ST-LINK/V2 to program/debug the on-board microcontroller
Figure 6 shows how to plug the two jumpers on CN3 to program the STM32L152RC on the
board. The usage of CN2 is forbidden as it might disturb communication with the
microcontroller.
Figure 6. 32L152CDISCOVERY connections
Both jumpers ON
(CN3)
SWD connector
(pin 1 of CN2)
MSv19053V3

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37
6.3.2 Using the ST-LINK/V2 to program/debug an external application
The ST-LINK/V2 allows also the programming of an STM32 device on an external
application. Figure 7 shows how to remove the two jumpers from CN3 and connect the
external application to the CN2 debug connector according to the instructions in Table 6.
Note: SB100 must be OFF if the CN2 pin 5 is used in the external application.
Figure 7. ST-LINK connections
Table 6. SWD debug connector (CN2)
Pin CN2 Designation
1 VDD_TARGET VDD from application
2 SWCLK SWD clock
3 GND Ground
4 SWDIO SWD data input/output
5 NRST RESET of target MCU
6SWOReserved
Both jumpers OFF
(CN3)
SWD connector
(pin 1 of CN2)
MSv19058V3

Hardware and layout UM1079
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6.4 Power supply and power selection
The power supply is provided either by the host computer through the USB cable, or by an
external 5 V or 3.3 V power supply.
The D1 and D2 protection diodes allow using the EXT_5V and EXT_3V pins independently
as input or output power supplies (refer to Figure 3):
•EXT_5V and EXT_3V can be used as output power supplies when the application
board is connected to pins P1 and P2. In this case, the EXT_5V and EXT_3V pins
deliver a 5 V or 3 V power supply and power consumption must be lower than 100 mA.
•EXT_5V and EXT_3V can also be used as input power supplies when the USB
connector is not connected to the computer. In this case, a power supply unit or
auxiliary equipment complying with standard EN-60950-1: 2006+A11/2009 must
provide the power to the board. This power source must be safety extra low voltage
(SELV) with limited power capability.
Battery-powered (optional)
The 32L152CDISCOVERY board has been designed to run from a CR2032 standalone
battery (no connection with USB or other power supply is required).
By default, no battery holder is mounted on the board, and SB21 and SB22 are configured
in their default state (refer to Table 7).
Follow the procedure below to power the 32L152CDISCOVERYfrom the battery:
•Solder a B7410AP2L battery holder from LOTES on CR1
•Configure SB100 OFF
•Remove both jumpers from CN3 (refer to Figure 7)
•Select the battery as a power supply. Two solutions are possible:
– Solder bridge: configure SB21 OFF and SB22 ON. No header is required on JP2.
– Jumper: configure SB21 and SB22 OFF. Solder a header on JP2, identical to JP1
on the top side. Set a jumper between VDD and VBAT to power the
STM32L152RC of the board
Note: In this configuration, it is possible to power the STM32L152RC from the 3 V supply voltage
of the board by setting a jumper between VDD and 3V.
•Plug the CR2032 battery into the CR1 holder.
The demonstration is now ready to run.
Warning: Wrong solder bridge configuration can damage the board
components.

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37
6.5 LEDs
•COM LED: LD1 default status is red. LD1 turns to green to indicate that the
communications are in progress between the computer and the ST-LINK/V2.
•PWR LED: Red LD2 indicates that the board is powered.
•User LD3: This user green LED is connected to the PB7 I/O of the STM32L152RC.
•User LD4: This user blue LED is connected to the PB6 I/O of the STM32L152RC.
6.6 Push-buttons
•B1 USER: The user push-button is connected to the I/O PA0 of the MCU.
•B2 RESET: The reset push-button is used to reset the MCU.
6.7 Linear touch sensor and touchkeys
To demonstrate touch sensing capabilities, the 32L152CDISCOVERY includes a linear
touch sensor that can be used either as a 3-position linear touch sensor or as four
touchkeys. Both functionalities are illustrated in the demonstration software (refer to
Table 4).
Three pairs of I/O ports are assigned to the linear touch sensor and the touchkeys. Each
pair must belong to the same analog switch group:
•PA6, PA7 (group 2)
•PC4, PC5 (group 9)
•PB0, PB1 (group 3)
To minimize the noise, these pairs are dedicated to the linear touch sensor and the
touchkeys and are not connected to external headers.
To design a touch-sensing application, refer to the following documentation and firmware:
•For details concerning I/O ports, refer to the STM32L152RC datasheet.
•For information on software development, refer to Discovery application software at
www.st.com/mcu.
•For more detail concerning touch sensing application design and layout, refer to the
application note Guidelines for designing touch sensing applications with surface
sensors (AN4312).
•STM32 touch-sensing library available from www.st.com/mcu

Hardware and layout UM1079
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6.8 Built-in IDD measurement circuit
The 32L152CDISCOVERY built-in IDD measurement circuit allows measuring the
consumption of the STM32L152RC and displaying the value on the LCD glass while the
MCU is in Run or Low-power modes.
•JP1 ON: The STM32L152RC is powered through the IDD measurement circuit
(default).
•JP1 OFF: The STM32L152RC is directly powered. The IDD measurement circuit is
bypassed.
Note: When jumper JP1 is removed, the current consumption of the STM32L152RC can be
measured by connecting an ammeter between jumper pin 1 and pin 2 of JP1.
To perform the IDD measurement by the MCU itself, the circuit shown in Figure 8 is
implemented on the 32L152CDISCOVERY. The solder bridges (SB1, SB2, and SB14) and
jumper (JP1) must be ON. The low IDD range procedure (refer to Section 6.8.2) is
recommended when the MCU is in Low-power mode and the IDD current does not exceed
60 A. The high IDD range procedure (refer to Section 6.8.1) is applicable when the MCU
operates in Run mode and can sink up to 30 mA.
Figure 8. IDD measurement circuit
6.8.1 High IDD range mode
In high IDD range mode, the IDD current is measured using the operational amplifier
MAX9938FEUK+ (U5) connected to the 2 shunt resistor (R21). In this case,
IDD_CNT_EN remains high during the measurement. R22 remains in short-circuit during
the measurement because the FET transistor 1 of U20 remains ON permanently.
MSv19054V2
R2 0
47K
PA 4
PC1 3
PA 0
2
3
4
5
U7
74 L X 1G04CT R
I/O
1O/I 2
GN D
3C
4
VCC 5
U6
74H 1G66STR
VD D
R2 1
2(1% )
R2 2
1K(1%)
VD D
Q1 2
1
Q1 3
2
Q1 4
3
Q6
4
Q5
5
Q7
6
Q4
7
GN D
8CO 9
CO 10
CI 11
CL R 12
Q9 13
Q8 14
Q1 0 15
VCC 16
U3
M74HC4 060TT R
VD D
VD D
R2 5
10K
R1 8
10K C1 3
1uF
VDD _MC U
1
2
3
JP 1
C1 5
1nF
R2 3
15K
R2 4
30K
VD D
R1 9
0
IDD_ Measure ment
IDD_W A K E UP
IDD_CN T _E N
C1 4
100n F
SB2
SB 1
SB1 4
I
DD
measurement
onoff
4
5
2
3
1
U5
MA X 9938FEUK+
VD D
S1
1D1 8
G1
2D1 7
S2
3D2 6
G2
4D2 5
U2 0
STS 4DP F20 L
Oscillator frequency 30 KHz