The TCA8418 is a keypad scan device with integrated ESD protection. It can operate from 1.65 V to 3.6 V and has 18 general purpose inputs/outputs (GPIO) that can be used to support up to 80 keys via the I2C interface.
The key controller debounces inputs and maintains a 10 byte FIFO of key-press and release events which can store up to 10 keys with overflow wrap capability. An interrupt (INT) output can be configured to alert key presses and releases either as they occur, or at maximum rate.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
TCA8418 | WQFN (24) | 4.00 mm × 4.00 mm |
Changes from F Revision (July 2017) to G Revision
Changes from E Revision (November 2015) to F Revision
Changes from D Revision (July 2014) to E Revision
Changes from B Revision (March 2010) to C Revision
PIN | TYPE | DESCRIPTION | |
---|---|---|---|
No. | NAME | ||
1 | ROW7 | I/O | GPIO or row 7 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
2 | ROW6 | I/O | GPIO or row 6 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
3 | ROW5 | I/O | GPIO or row 5 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
4 | ROW4 | I/O | GPIO or row 4 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
5 | ROW3 | I/O | GPIO or row 3 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
6 | ROW2 | I/O | GPIO or row 2 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
7 | ROW1 | I/O | GPIO or row 1 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
8 | ROW0 | I/O | GPIO or row 0 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
9 | COL0 | I/O | GPIO or column 0 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
10 | COL1 | I/O | GPIO or column 1 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
11 | COL2 | I/O | GPIO or column 2 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
12 | COL3 | I/O | GPIO or column 3 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
13 | COL4 | I/O | GPIO or column 4 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
14 | COL5 | I/O | GPIO or column 5 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
15 | COL6 | I/O | GPIO or column 6 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
16 | COL7 | I/O | GPIO or column 7 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
17 | COL8 | I/O | GPIO or column 8 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
18 | COL9 | I/O | GPIO or column 9 in keypad matrix. If unused, connect to VCC through a pull-up resistor. |
19 | GND | – | Ground |
20 | RESET | I | Active-low reset input. Connect to VCC through a pull-up resistor, if no active connection is used. |
21 | VCC | - | Supply voltage of 1.65 V to 3.6 V |
22 | SDA | I/O | Serial data bus. Connect to VCC through a pull-up resistor. |
23 | SCL | I | Serial clock bus. Connect to VCC through a pull-up resistor. |
24 | INT | O | Active-low interrupt output. Open drain structure. Connect to VCC through a pull-up resistor. |