Texas Instruments TCA8418 I2C User manual

TCA8418 I2C Controlled Keypad Scan IC
Evaluation Module
User's Guide
Literature Number: SCPU033
May 2010

2SCPU033–May 2010
Copyright © 2010, Texas Instruments Incorporated

Preface ....................................................................................................................................... 5
1 Introduction ........................................................................................................................ 7
1.1 List of Hardware Items for Operation ................................................................................. 7
1.2 List of Software Items for Operation .................................................................................. 7
1.3 Step-by-step Instructions for Operation and Troubleshooting ..................................................... 7
1.4 Hardware Uninstall Instructions ....................................................................................... 7
1.5 Software Uninstall Instructions ........................................................................................ 8
2 EVM Configuration and Description ....................................................................................... 8
2.1 EVM Options ............................................................................................................. 8
2.2 EEPROM (U1) and JMP10 ............................................................................................. 8
2.3 LED (D1) Indication of USB Attached ................................................................................ 8
2.4 Test Point Connectors (TP1 through TP5) ........................................................................... 8
2.5 Jumper Configuration (JMP1 through JMP6) ........................................................................ 9
2.6 Schematics ............................................................................................................. 12
2.7 Bill of Materials ......................................................................................................... 14
3 GUI Configuration and Description ...................................................................................... 16
3.1 GUI Installation ......................................................................................................... 16
3.2 GUI Functionality ....................................................................................................... 17
3.2.1 Keypad Mode ............................................................................................... 17
3.2.2 Overflow Mode ............................................................................................. 18
3.2.3 GPIO Mode ................................................................................................. 19
3.2.4 Registers and I2C........................................................................................... 20
4 Related Documentation from Texas Instruments ................................................................... 21
3
SCPU033–May 2010 Table of Contents
Copyright © 2010, Texas Instruments Incorporated

www.ti.com
List of Figures
1 Jumper Configuration: JMP1 and JMP2................................................................................ 10
2 Jumper Configuration: JMP3 and JMP4................................................................................ 10
3 Jumper Configuration: JMP5............................................................................................. 11
4 Jumper Configuration: JMP6, JMP7, JMP8, JMP9 ................................................................... 11
5 Schematics (1 of 2)........................................................................................................ 12
6 Schematics (2 of 2)........................................................................................................ 13
7 TCA8418 EVM GUI Files................................................................................................. 16
8 TCA8418 EVM Application Installation ................................................................................. 16
9 TCA8418 EVM GUI: Keypad Mode..................................................................................... 17
10 TCA8418 EVM GUI: Overflow Mode.................................................................................... 18
11 TCA8418 EVM GUI: GPIO Mode ....................................................................................... 19
12 TCA8418 EVM GUI: Registers and I2C................................................................................. 20
List of Tables
1 Test Point Descriptions..................................................................................................... 8
2 Jumper Descriptions........................................................................................................ 9
3 Bill of Materials............................................................................................................. 14
4List of Figures SCPU033–May 2010
Copyright © 2010, Texas Instruments Incorporated

Read This First
SCPU033–May 2010
Preface
About This Manual
This user guide describes the functions and operation of TCA8418 Evaluation Module (EVM), including
hardware design, graphical user interface (GUI), and EVM setup.
How to Use This Manual
This document contains the following chapters:
• Chapter 1 – Introduction and Quick Start
• Chapter 2 – EVM Configuration and Description
• Chapter 3 – GUI Configuration and Description
• Chapter 4 – Schematic and Layout
Information about Cautions and Warnings
The information in a caution or a warning is provided for your protection. Please read each caution and
warning carefully.
CAUTION
This EVM contains components that can potentially be damaged by
electrostatic discharge. Always transport and store the EVM in its supplied ESD
bag when not in use. Handle using an antistatic wristband. Operate on an
antistatic work surface. For more information on proper handling, see the
application report Electrostatic Discharge (ESD) (SSYA008)
CAUTION
By default, the I2C data and clock lines at TP3 and TP4 are pulled up internally
to TCA8418 supply voltage (1.8 V to 3.3 V) through jumper JMP7 configuration.
If external pullup resistors are used instead, make sure to pull up to 3.3 V only.
Operation from 5 V is not specified and may permanently damage this EVM.
All trademarks are the property of their respective owners.
5
SCPU033–May 2010 Preface
Copyright © 2010, Texas Instruments Incorporated

FCC Warning www.ti.com
FCC Warning
This equipment is intended for use in a laboratory test environment only. It generates, uses, and can
radiate radio frequency energy and has not been tested for compliance with the limits of computing
devices pursuant to subpart J of part 15 of FCC rules, which are designed to provide reasonable
protection against radio frequency interference. Operation of this equipment in other environments may
cause interference with radio communications, in which case the user at his/her own expense will be
required to take whatever measures may be required to correct this interference.
6Preface SCPU033–May 2010
Copyright © 2010, Texas Instruments Incorporated

User's Guide
SCPU033–May 2010
TCA8418 I2C Controlled Keypad Scan IC Evaluation
Module
1 Introduction
The TCA8418 EVM is an evaluation module (EVM) for the Texas Instruments (TI) inter-integrated circuit
(I2C) controlled keypad scan IC. The TCA8418 keypad scan IC operates from supply voltage range of 1.65
V to 3.3 V. It offers high level of electrostatic discharge (ESD) protection and supports 1-MHz Fast Mode
Plus I2C bus. With 18 configurable GPIO pins, it can be configured to support 10x8 keypad array. This
operation frees the processor from scanning the keypad for presses and releases, thus saving power and
bandwidth of the system.
The TCA8418 EVM serves as an I2C interface adapter between a host PC (IBM compatible), the
TCA8418, and/or other I2C compatible devices externally connected to the EVM. The communication
between EVM and the host PC is via USB (through a standard type-A to type-B USB cable), while the
communication between the EVM, the TCA8418, and/or other slave devices is via I2C bus. The EVM
converts communication transactions between the USB and I2C.
1.1 List of Hardware Items for Operation
To operate the TCA8418 EVM, these items are required:
• The TCA8418 EVM
• Standard type-A to type-B USB cable
• IBM compatible PC with Microsoft Windows XP or later operating system installed
1.2 List of Software Items for Operation
In addition to the hardware items listed in Section 1.1, this software is required:
• Demo GUI Software (TCA8418.exe)
The software can be downloaded from the TI website at www.ti.com.
The EVM is recognized by a PC as a generic human interface device (HID), which is supported by the
built-in USB/HID drivers of the Windows XP or later operating system. Therefore, it is plug-and-play and
no proprietary USB driver is required.
1.3 Step-by-step Instructions for Operation and Troubleshooting
After downloading and installing the GUI demo software, follow these steps to operate the EVM:
1. Plug the USB cable into both the PC and the EVM and wait for the LED to illuminate.
Troubleshooting: If the LED does not illuminate after 30 seconds, make sure that the USB cable is
securely connected. If the connection is secure, try a different USB port. If a different USB port does
not solve the problem, try to reboot the computer. If rebooting the computer does not fix the problem,
try a different USB cable. If a different USB cable does not solve the problem, contact TI technical
support for help.
2. Run the TCA8418 EVM GUI software and follow the instructions for the GUI.
1.4 Hardware Uninstall Instructions
Unplug the EVM from the USB port to uninstall the hardware from the host PC.
7
SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

EVM Configuration and Description www.ti.com
1.5 Software Uninstall Instructions
For Windows operating system, go to Control Panel > Add or Remove Programs to remove the TCA8418
GUI software.
2 EVM Configuration and Description
2.1 EVM Options
The hardware is based on a USB peripheral chip from TI (TUSB3210). The TUSB3210 has an 8052 core
with enhanced performance. The PCB is a simple two-layer top-side populated board (see the schematic
in Section 2.6). The major features of the hardware design are detailed in the following sections.
2.2 EEPROM (U1) and JMP10
The embedded firmware is stored in a 64-kbit EEPROM (see U1 in the schematic in Section 2.6). The
firmware is field programmable. Jumper JMP10 is normally closed and is used for firmware development
only. On power up, the TUSB3210 downloads the firmware image from the EEPROM to the internal static
RAM and starts firmware execution (first with USB enumeration) from there.
2.3 LED (D1) Indication of USB Attached
A white LED is mounted next to the TUSB3210 IC (U4) on the evaluation board. Every time the USB
interface adapter is attached to a PC via a USB cable, and if the host PC detects it and goes through USB
enumeration successfully, the embedded firmware illuminates the white LED (D1); otherwise, the LED
remains off. After unplugging the USB cable, the LED turns off immediately.
2.4 Test Point Connectors (TP1 through TP5)
Test point connectors TP1 through TP5 allow the users to connect both external signal sources and
external I2C slave devices to the EVM. Table 1 describes the functions of all of the test points in the EVM.
Table 1. Test Point Descriptions
Test Point Functionality Configuration
To either monitor or supply to To supply TCA8418 IC reset externally , the external I/O logic level must be the
TP1 TCA8418 IC reset signal same as TCA8418 IC.
To monitor TCA8418 IC
TP2 interrupt signal
To either monitor or supply to To supply TCA8418 IC SCL externally , the external I/O logic level must be the
TP3 TCA8418 IC I2C SCL line same as TCA8418 IC.
To either monitor or supply to To supply TCA8418 IC SDA externally , the external I/O logic level must be the
TP4 TCA8418 IC I2C SDA line same as TCA8418 IC.
To either monitor or supply to To supply TCA8418 IC VCC externally , U5 must be disabled by shunting 2-3 on
TP5 TCA8418 VCC JMP4.
TP6 Ground test point
TP7 Ground test point
TP8 Ground test point
8SCPU033–May 2010
TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

www.ti.com EVM Configuration and Description
External Microcontroller Control
The user can provide external microcontroller I2C and GPIO connections to the EVM by routing them to
test points TP1 to TP4.
Before connecting the microcontroller, check the following:
• Make sure the I/O voltage of the external microcontroller is the same as the I/O voltage of the
TCA8418. The power supply voltage of the TCA8418_VCC can be adjusted through JMP5 or
externally supplied through TP5 with U5 disabled by JMP4 (see Section 2.5).
• Make sure the external microcontroller is isolated from the TUSB3210 by disabling the TXS0104E level
translator. Shorting jumper JMP2 can disable the level translator (see Section 2.5).
External I2C Slave Devices
The user can connect external I2C slave devices to test points TP3 and TP4. The devices can be
controlled through the TCA8418 graphical user interface (GUI) software. Under the GUI software control,
the I2C bus operates at 400 kHz. Therefore, the external slave devices must support 400-kHz I2C bus.
2.5 Jumper Configuration (JMP1 through JMP6)
To use the full TCA8418 (GUI) software functionality, all jumpers except JMP5 must be at their default
settings. Table 2 describes all of the jumpers in the EVM and their respective functionality (all default
settings are in bold).
Table 2. Jumper Descriptions
Jumper Functionality Configuration
TCA8418 Keypad Scanner IC Open JMP1 to allow GUI control
JMP1 Disable Shunt JMP1 to disable TCA8418 manually
TXS0104E Level Translator Open JMP2 to enable level translation
JMP2 Disable Shunt JMP2 to disable level translation
LP2985-33 5V to 3.3V LDO Shunt JMP3 in 1-2 position to enable the 3.3V LDO
JMP3 Disable Shunt JMP3 in 2-3 position to disable the 3.3V LDO
TPS73101 5V to Variable Shunt JMP4 in 1-2 position to enable the Variable Output LDO
JMP4 Output LDO Disable Shunt JMP4 in 2-3 position to disable the Variable Output LDO
TPS73101 5V to Variable Shunt 1-2 for TCA8418_VCC = 1.8V
JMP5 Output LDO Adjust Shunt 2-3 for TCA8418_Vcc = 3.3VOpen all for TCA8418_Vcc = 2.4V
TCA8418 ROW6 Function Shunt 1-2 for GPI functionality
JMP6(1) Selection Shunt 2-3 for Keypad functionality
TCA8418 ROW7 Function Shunt 1-2 for GPI functionality
JMP7(1) Selection Shunt 2-3 for Keypad functionality
TCA8418 COL8 Function Shunt 1-2 for GPO functionality
JMP8(1) Selection Shunt 2-3 for Keypad functionality
TCA8418 COL9 Function Shunt 1-2 for GPO functionality
JMP9(1) Selection Shunt 2-3 for Keypad functionality
Open JMP6 to open EEPROM SCL line for firmware programming
JMP10 EEPROM SCL Line Short Shunt JMP4 to short EEPROM SCL line
(1) JMP6, JMP7, JMP8, and JMP9 must all have the same configuration for correct GUI operation.
9
SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

10 kW
TCA8418_VCC
JMP1
To TUSB3210 To TCA8418 Enable
TCA8418_VCC
JMP2
To TXS0104E Enable
10 kW
USB_5V
JMP3 and JMP4
To LDO Enable
1
2
3
Enable
Disable
EVM Configuration and Description www.ti.com
Jumpers JMP1, JMP2, JMP3, and JMP4 allow the user to manually enable and disable TCA8418 (U3),
TXS0104E (U2), LP2988-33 (U7), and TPS73101 (U5), respectively. Jumpers JMP1 and JMP2 are
two-pin headers with pin 1 pulled up to TCA8418_VCC through 10-kΩresistors (see Figure 1). Jumpers
JMP3 and JMP4 are three-pin headers with two jumper configurations (see Figure 2).
Figure 1. Jumper Configuration: JMP1 and JMP2
To enable both the TCA8418 and the TXS0104E, leave both JMP1 and JMP2 open. Through the GUI
software, the TUSB3210 microcontroller (U4) detects the on/off state of the TCA8418 IC (U3). When
JMP1 is open, the TCA8418 EVM software has the full control of the TCA8418 IC through TUSB3210
microcontroller. To manually disable the TCA8418 IC, shunt JMP1 to drive the active-low reset input of the
TCA8418 to logic low.
JMP2 controls the TXS0104E level translator. The TCA8418 IC and other externally connected I2C slave
devices are on side A of the TXS0104E, while the TUSB3210 microcontroller is on side B of the
TXS0104E. Side A logic level is referred to the power supply level of the TCA8418, which ranges from
1.65 V to 3.6 V. As mentioned in Section 2.4, the TCA8418_VCC can be externally supplied through TP5
when TPS73101 (U5) is disabled through JMP4, or it can be supplied through the TPS73101 with output
voltages of 1.8 V, 2.3 V, or 3.3 V depending on JMP5 configuration. Side B logic level remains fixed to the
3.3-V power supply voltage of the TUSB3210.
Figure 2. Jumper Configuration: JMP3 and JMP4
If external sources of SCL, SDA, interrupt, and reset signals to the TCA8418 IC are used, disable the
TXS0104E and the TPS73101 ICs through JMP2 and JMP4 before connecting the external signals. JMP3
and JMP4 (see Figure 2) can enable or disable the output of the LP2985-33 or the TPS73101 LDO ICs.
To enable the LDOs, shunt pins 1 and 2 of the JMP3 and JMP4 to tie the enable pins of the LDO ICs to
USB_5V. To disable the LDOs, shunt pins 2 and 3 of the JMP3 and JMP4 to tie the enable pins to ground.
10 SCPU033–May 2010
TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

JMP5
1
2
3
28 kW
24.3 kW
26.1 kW
30.1 kW
TCA8418_VCC
1.8 V
3.3 V
Open = 2.4 V
To LDO feedback
1
2
3
TCA8418_VCC
JMP6
JMP7
GPI Function
Keypad Function
JMP8
JMP9
1
2
3
USB_5V
Keypad Function
GPO Function
www.ti.com EVM Configuration and Description
Jumper JMP5 (see Figure 3) allows adjustment of the TCA8418_VCC voltage to 1.8 V, 2.4 V, or 3.3 V.
This provides the flexibility to evaluate TCA8418 under different supply voltages. Short pins 1 and 2 to
provide 1.8-V output, and short pins 2 and 3 to provide 3.3-V output. Open the JMP5 to provide 2.4-V
output.
Figure 3. Jumper Configuration: JMP5
Jumpers JMP6, JMP7, JMP8, and JMP9 (see Figure 4) configure the TCA8418 EVM to either a 8x6
keypad controller with two GPIs and two GPOs or a full 10x8 keypad controller scanner.
• To configure Row 6 and Row 7 to be in GPI mode, shunt JMP6 and JMP7 in 1-2 position.
• To configure Column 8 and Column 9 to be in GPO mode, shunt JMP8 and JMP9 in 1-2 position.
• To configure the EVM to be in the full 10x8 keypad matrix mode, shunt JMP6 through JMP9 in 2-3
position.
NOTE: JMP6, JMP7, JMP8, and JMP9 must have the same configuration for a correct GUI
operation.
Figure 4. Jumper Configuration: JMP6, JMP7, JMP8, JMP9
11
SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

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Schematic Title
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Size Document Numb er Rev Sheet
TCA8418 Evaluation Module
RSV
1
NC
2
NC
3
RSV
4
GND
5
NC
6
NC
7
S2
8
S3
9
VCC
10
SDA
11
SCL
12
nRST
13
TEST0
14
TEST1
15
SUSP
16
PUR
17
DP
18
TEST2
20
GND
21
P2.0
22
P2.1
23
GND
24
P2.2
25
P2.3
26
P2.4
27
P2.5
28
P2.6
29
P2.7
30
P1.0
31
P1.1
32
DM
19
P1.2 33 P1.3 34 P1.4 35 P1.5 36
VDDOUT 37
nVREN 38
VCC 39
P1.6 40 P1.7 41
GND 42
P0.0 43 P0.1 44 P0.2 45 P0.3 46 P0.4 47 P0.5 48
P0.6 49
P0.7 50
P3.7 51
P3.6 52
P3.5 53
P3.4 54
P3.3 55
P3.2 56
P3.1/ S1 57
P3.0/ S0 58
GND 59
X2 60
X1 61
VCC 62
NC 63
NC 64
U4
TUSB3210
uC_SCL
uC_SDA
R14
1M
Y1
12MHz
C2
22pF
C3
22pF
R19
15K
C8
1uF
C7
0.1uF
R23
33
R24
33
R20
15K
C13
0.1uF
R28
100K
R26
100K
R27
100K
C11
1uF
C1
0.1uF
R3
33
V+ 1
DM 2
DP 3
GND 4
J1
USB
R4
33
SDA 5
SCL 6
WP 7
VCC 8
A0
1
A1
2
A2
3
VSS
4
U1 24LC64
R22
1.5k
USB_5V
3p3V
R21
100K
3p3V
3p3V
R13
1.5k
R12
1.5k
3p3V
C9
0.1uf
C10
1uF
Vin
1
GND
2
Enable
3
Vout 5
Bypass 4
U7 LP2985-33-SOT23
USB_5V
C17
1uF
1
2
JMP1
MAN_RST
1
2
3JMP3
3p3V_EN
TCA8418_Vcc
R11
10k
C18
0.01uF
R16
DNI
C19
2.2uF
R15
DNI
3p3V
TCA8418_Vcc
C6
1uF
USB Port
ESD Protection
3p3V
R2
33
TCA_SCL
TCA_SDA TCA_INT
uC_Int
USB_DM
USB_DP
uC_PUR
3p3V
Q1_B
Q1_E
USB 5V to 3.3V Regulation
uC_DP
uC_DM
mem_SCL
mem_SDA
uC_RSET
uC_SUS
uC_X1
uC_X2
TCA8418 EVM Revision History:
e1p0: initial engineering design.
e1p1: changed uC_Int from p0.3 to p3.3
changed uC_RST from p0.4 to p3.2
e1p2: added J6 to the EEPROM SCL line for On-Board
EEPROM Programming
added uC_RST_Sense line on GPIO P3.4
added D2 thru D5 to prevent ghosting on k
ey 1, 2, 11, 12
changed the U5 LP2985-18 to TPS73101 adju
stable
e1p3 added Diodes D1 to D80 for ghosting protectio
n
added JMP6, JMP7, R35, R36, S81, S82 for
GPI operation
added JMP8, JMP9, R33, R34, R37, R38, Q2,
Q3, D82, D83 for GPO operation
EEPROM
LDO_EN2
LDO_By2
R1
33
uC_Rst
TCA_RST
TCA8418_Vcc
R10
10k
1
TP5
EXT_VCC
C16
0.1uF
R18
DNI
R5
DNI
TCA8418_Vcc
1
2
JMP2
EXT_I2C
TCA8418_Vcc
R17
10k
TCA8418_Vcc
Strap JMP2 in 1-2 Position
1. to disable TXS0104 outputs
2. allows external control signals
Strap 1-2 in JMP1 for Manual Reset
JMP3 Configuration:
1-2 Position = LDO Enable
2-3 Position = LDO Disable
Inject external reset, interrupt,
SCL, and SDA signal to TCA8418
by using TP1, TP2, TP3, and TP4
VccA 1
A1 2 A2 3 A3 4 A4 5
NC 6
GND 7
OE
8
NC
9
B4
10
B3
11
B2
12
B1
13
VccB
14
U2 TXS0104E 3p3V
C5
0.1uF
C4
0.1uF
R6
33
R7
33
R8
33
R9
33
nINT
24
SCL
23
SDA
22
nRESET
20
VCC 21
GND 19
U3C
TCA8418_QFN
IO1
1
GND
3IO3 4
IO2
2
Vcc 5
U6
TPD3E001-DRL
USB_5V
D81
LTW-170TK
R25 200
Q1
MMBT2222A
1
TP1
ext_RST
1
TP2
ext_INT
1
TP3
ext_SCL
1
TP4
ext_SDA
1
2
JMP10
SCL_ISO
uC_Rst_Sense
1
TP6
GND1
1
TP7
GND2
1
TP8
GND3
Vin
1
GND
2
Enable
3
Vout 5
Bypass 4
U5 TPS73101
USB_5V
C12
1uF
1
2
3JMP4
1p8V_EN
C14
0.01uF
C15
2.2uF
TCA8418_Vcc
USB 5V to 1.8V/3.3V Regulation
LDO_EN1
LDO_By1
R29
28k
R30
24.3k
R31
26.1k
R32
30.1k
1
2
3JMP5
Vout_SEL
JMP5 Configuration
1-2 Position = TCA8418_Vcc = 1.8V
2-3 Position = TCA8418_Vcc = 3.3V
Open = TCA8418_Vcc = 2.4V
SHEET2
JMP4 Configuration:
1-2 Position = LDO Enable
2-3 Position = LDO Disable
Caution:
Disable U5 before supplying external Vcc
Texas Instruments TCA8418 Evaluation Module
EVM Configuration and Description www.ti.com
2.6 Schematics
Figure 5. Schematics (1 of 2)
12 SCPU033–May 2010
TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

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Schematic Title
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TCA8418 Evaluation Module
ROW7 1 ROW6 2 ROW5 3 ROW4 4 ROW3 5 ROW2 6 ROW1 7 ROW0 8
U3A
TCA8418_QFN
S01 S02 S03 S04 S05 S06 S07 S08 S09 S10 S11 S12 S13 S14 S15 S16 S17 S18 S19 S20 S21 S22 S23 S24 S25 S26 S27 S28 S29 S30 S31 S32 S33 S34 S35 S36 S37 S38 S39 S40 S41 S42 S43 S44 S45 S46 S47 S48 S49 S50 S51 S52 S53 S54 S55 S56 S57 S58 S59 S60 S61 S62 S63 S64 S65 S66 S67 S68 S69 S70 S71 S72 S73 S74 S75 S76 S77 S78 S79 S80
COL1
10
COL2
11
COL3
12
COL4
13
COL5
14
COL6
15
COL7
16
COL8
17
COL9
18
COL0
9
U3B
TCA8418_QFN
ROW0 ROW1 ROW2 ROW3 ROW4 ROW5
ROW6
ROW7
COL0
COL1
COL2
COL3
COL4
COL5
COL6
COL7
COL8
COL9
TCA8418 QFN
D01 D02 D03 D04 D05 D06 D07 D08 D9 D10 D11 D12 D13 D14 D15 D16 D17 D18 D19 D20 D21 D22 D23 D24 D25 D26 D27 D28 D29 D30 D31 D32 D33 D34 D35 D36 D37 D38 D39 D40 D41 D42 D43 D44 D45 D46 D47 D48 D49 D50 D51 D52 D53 D54 D55 D56 D57 D58 D59 D60 D61 D62 D63 D64 D65 D66 D67 D68 D69 D70 D71 D72 D73 D74 D75 D76 D77 D78 D79 D80
1
2
3JMP8
C8_SEL
1
2
3JMP9
C9_SEL
D82
LTW-170TK
D83
LTW-170TK
R33
200
R34
200
USB_5V USB_5V
S82 S81
1
2
3
JMP6
R6_SEL
1
2
3
JMP7
R7_SEL
R35
10k
R36
10k
TCA8418_VCC TCA8418_VCC
Q2
MMBT2222A
Q3
MMBT2222A
R37
22.1k
R38
22.1k
Texas Instruments TCA8418 Evaluation Module
www.ti.com EVM Configuration and Description
Figure 6. Schematics (2 of 2)
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SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
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EVM Configuration and Description www.ti.com
2.7 Bill of Materials
Table 3. Bill of Materials(1)(2)(3)(4)(5)
Count RefDes Value Description Size Part Number Manufacturer
1 – – Two-Layer, 7200mil by 4800mil, PCB 7200mil x 4800mil TCA8418 EVM E2 Any
C1, C4, C5,
7 C7, C9, C13, 0.1uF Capacitor, Ceramic, 0.1uF, X7R, 10% 0603 Std Std
C16
2 C14, C18 0.01uF Capacitor, Ceramic, 0.01uF, X7R, 10% 0603 Std Std
2 C15, C19 2.2uF Capacitor, Ceramic, 2.2uF, X7R, 10% 0603 Std Std
Capacitor, Ceramic, 22pF, 50V, C0G,
2 C2, C3 22pF 0603 C1608C0G1H220KT TDK
10%
C6, C8, C10,
6 C11, C12, 1.0uF Capacitor, Ceramic, 1.0uF, X7R, 10% 0603 Std Std
C17
D1 through Comchip
80 Diodes Switching Diode, 75V, 150mA, 0603 0603 CDSU4148
D80 Technology
D81 through
3 LED White LED, 0805 0805 LTW-170TK Lite-On Inc.
D83
MOLEX/ WALDOM
1 J1 – USB Right Angle Recpt. Type B – 67068-9000 ELECTRONICS
JMP1, Sullins Connector
3 JMP2, – Header, 2x1pin, 100mil spacing 100mil x 100mil PEC36SAAN Solutions
JMP10
JMP3,
JMP4,
JMP5, Sullins Connector
7 – Header, 3x1pin, 100mil spacing 100mil x 100mil PEC36SAAN
JMP6, Solutions
JMP7,
JMP8, JMP9
Transistor, NPN, High Performance,
3 Q1, Q2, Q3 BJT SOT-23 MMBT2222A Fairchild
500mA
R1, R2, R3,
R4, R6, R7,
10 33ΩResistor, Chip, 33Ω, 1/8W, 5% 0603 Std Std
R8, R9, R23,
R24
R10, R11,
5 R17, R35, 10kΩResistor, Chip, 10kΩ, 1/8W, 5% 0603 Std Std
R36
R12, R13,
3 1.5kΩResistor, Chip, 1.5kΩ, 1/8W, 5% 0603 Std Std
R22
1 R14 1MΩResistor, Chip, 1MΩ, 1/8W, 5% 0603 Std Std
2 R19, R20 15kΩResistor, Chip, 15kΩ, 1/8W, 5% 0603 Std Std
R21, R26,
4 100kΩResistor, Chip, 100kΩ, 1/8W, 5% 0603 Std Std
R27, R28
R25, R33,
3 200ΩResistor, Chip, 200Ω, 1/8W, 5% 0603 Std Std
R34
1 R29 28.0kΩResistor, Chip, 28.0kΩ, 1/8W, 5% 0603 Std Std
1 R30 24.3kΩResistor, Chip, 24.3kΩ, 1/8W, 5% 0603 Std Std
1 R31 26.1kΩResistor, Chip, 26.1kΩ, 1/8W, 5% 0603 Std Std
1 R32 30.1kΩResistor, Chip, 30.1kΩ, 1/8W, 5% 0603 Std Std
2 R37, R38 22.1kΩResistor, Chip, 22.1kΩ, 1/8W, 5% 0603 Std Std
R5, R15,
4 DNI Resistor, Chip, 10kΩ, 1/8W, 5% 0603 Std Std
R16, R18
SW1 through
82 Switch 4 terminal tactile switch 6mm x 6mm EVQ-PAC04M Panasonic
SW82
TP1 through Keystone
8 Test Point Test Point 5011 Series 63mil in diameter 5011
TP8 Electronics
(1) These assemblies are ESD sensitive, ESD precautions shall be observed.
(2) These assemblies must be clean and free from flux and all contaminants. Use of no clean flux is not acceptable.
(3) These assemblies must comply with workmanship standards IPC-A-610 Class 2.
(4) Ref designators marked with an asterisk ('**') cannot be substituted. All other components can be substituted with equivalent
manufacturer's components.
(5) Maximum 30 grams placement pressure on WCSP-6 parts.
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TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
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www.ti.com EVM Configuration and Description
Table 3. Bill of Materials(1)(2)(3)(4)(5) (continued)
Count RefDes Value Description Size Part Number Manufacturer
IC, Serial EEPROM 64kb, 1.8V to 5.5V,
1 U1 EEPROM DIP 24LC64 Microchip
400kHz I2C max
IC, 4-bit bidirectional voltage-level
1 U2 TXS0104E SOIC-14 TXS0104ED TI
translator
1 U3 TCA8418 IC, I2C controlled keypad scanner QFN TCA8418RTWR TI
IC, USB, General Purpose, Device 480mil x 480mil
1 U4 TUSB3210 TUSB3210PM TI
Controller 64-LQFP
1 U5 TPS73101 IC, 150mA LDO regulator SOT23-5 TPS73101DBV TI
IC, 3-Channel +/-15kV ESD protection
1 U6 TPD3E001 SOT-5 TPD3E001DRL TI
array
1 U7 LP2985-33 IC, 150mA LDO regulator SOT23-5 LP2985-33DBV TI
ABLS-12.000MHz-
1 Y1 12MHz Crystal, 12MHz, 18pF, SMD 500mil x 190mil Abracon
B2-T
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SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

GUI Configuration and Description www.ti.com
3 GUI Configuration and Description
3.1 GUI Installation
1. Extract the zip file to a folder (see Figure 7).
Figure 7. TCA8418 EVM GUI Files
2. Open the setup.exe, and click Install to finish the GUI installation (see Figure 8).
Figure 8. TCA8418 EVM Application Installation
3. Open the GUI from Start > All Programs. For Windows XP, the link to run the TCA8418 EVM GUI is
installed to Start > All Programs > Texas Instruments > TCA8418 EVM.
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TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated

www.ti.com GUI Configuration and Description
3.2 GUI Functionality
The TCA8418 EVM consists of four tabs:
• Keypad Mode: provides evaluation of the 10x8 keypad scanner functionality
• Overflow Mode: provides evaluation of the scanner overflow functionality
• GPIO Mode: provides evaluation of the GPIO functionality through push buttons and LEDs
• Registers and I2C: display register settings as well as providing I2C master read/write functionality
3.2.1 Keypad Mode
The keypad mode provides evaluation for the TCA8418 IC 10x8 keypad scanning mode (see Figure 9).
Make sure that jumpers JMP6, JMP7, JMP8, and JMP9 are shunted in the 2-3 position in this mode. Note
that the keypad buttons on the GUI are to display the button press/release actions corresponding to the
EVM buttons. Therefore, they are for display purpose only and have no actions associated with them.
Figure 9. TCA8418 EVM GUI: Keypad Mode
The buttons for the keypad mode tab are:
On/Off: Enable or disable the TCA8418 EVM
Lock/Unlock: Lock or unlock the TCA8418 EVM. During locked mode, press keys S9 and S10 on the
EVM to unlock the EVM.
Clear Screen: Clear the key screen
Clear History: Clear the key history screen
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SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
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GUI Configuration and Description www.ti.com
3.2.2 Overflow Mode
The overflow mode provides evaluation for the TCA8418 overflow mode (see Figure 10). Make sure that
jumpers JMP6, JMP7, JMP8, and JMP9 are shunted in the 2-3 position in this mode. Follow the
instructions listed on the GUI to observe the change in key history as the key press/release actions
exceed the 10 byte FIFO.
Figure 10. TCA8418 EVM GUI: Overflow Mode
The button for the overflow mode tab are:
On/Off: Enable or disable the TCA8418 EVM
Overflow On/Off: Enable or disable the overflow mode
Read Keys: Read the key events from the key event registers through I2C
Clear History: Clear the key history screen.
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TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
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www.ti.com GUI Configuration and Description
3.2.3 GPIO Mode
The GPIO mode provides evaluation for the TCA8418 with 2 inputs and 2 outputs (see Figure 11). Make
sure that jumpers JMP6, JMP7, JMP8, and JMP9 are shunted in the 1-2 position in this mode.
Figure 11. TCA8418 EVM GUI: GPIO Mode
The buttons for the GPIO mode tab are:
On/Off: Enable or disable the TCA8418 EVM. When the TCA8418 EVM is enabled through this button,
it is configured in a 8x6 keypad matrix with two GPIs on Row 6 and Row 7 and two GPOs on Column 8
and Column 9.
S81: Corresponds to the key S81 press/release action. Display purpose only, no response when
pressed within the GUI.
S82: Correspond to the key S82 press/release action. Display purpose only, no response when
pressed within the GUI.
On/Off for D82: Turn on or off LED D82.
On/Off for D83: Turn on or off LED D83.
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SCPU033–May 2010 TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
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GUI Configuration and Description www.ti.com
3.2.4 Registers and I2C
The Registers and I2C mode provides a clear view on all of the TCA8418 IC register status on one page
(see Figure 12). It also provides I2C bus master function, which can write and read other I2C slave devices
on the same bus.
Figure 12. TCA8418 EVM GUI: Registers and I2C
The buttons for the overflow mode tab are:
On/Off: Enable or disable the TCA8418 EVM
I2C Write: Allow the TCA8418 EVM to behave like an I2C bus master to write to other I2C slave devices
in addition to the TCA8418. Enter the chip address (in HEX), command byte (in HEX), and data (in
binary) on the corresponding section and press I2C Write. The I2C Write Status indicates the I2C
transaction result.
I2C Read: Allow the TCA8418 EVM to behave like an I2C bus master to read other I2C slave devices in
addition to the TCA8418. Enter the chip address (in HEX), command byte (in HEX) and press I2C
Read. The read results are displayed on the corresponding section, and the I2C Read Status indicates
the I2C transaction result.
I2C Read All TCA8418 Registers: Read all of the TCA8418 registers
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TCA8418 I2C Controlled Keypad Scan IC Evaluation Module
Copyright © 2010, Texas Instruments Incorporated