An Overview of TTP229 Module
The TTP229 Capacitive Touch Keypad is a semiconductor-based touchpad that is a reliable alternative to classic keyboards with switches. This capacitive touch sensor module has the TTP229 IC with sensitive touchpads that are an excellent replacement for the old-fashioned keypads. Module Capacitive touch allows sensing when a finger is within a few millimeters. We may use capacitive sensing in any place where low to no force of human touch sensing is needed.
Keypad of Module
TTP229 Capacitive Touch Module is a conventional 4×4 keypad with a touch-based keypad. The module allows two working modes. First, an 8 key mode that gives an independent 8 channel output. And, a 16 key mode that can be used with the I2C interface of the module, saving more pins of the microcontroller board. Through capacitance, one can adjust the sensitivity.
Features and Specification of TTP229 Module
Features
- 16-channel maximum touch key sensing
- Operating voltage – 2.4V – 5.5V for built-in regulator mode
- Operating voltage – 2.0V – 5.5V for built-in regulator disabled
- Inbuilt regulator for touch sensors
- Operating current 2.5uA typically in 16-key mode. Operating current 2.0uA for 8-key mode.
- I2C enabled for communication with host.
- Adjustable sensitivity using an external capacitor (1-50 pF)
- Stable touch detection of the human body
- All output modes can be configurable for high or active low by pad options.
- Direct mode and Toggle mode selection pin available
- Provides one output pin TPQ0D that has no diode protection circuit inbuilt and it is active low
- Provides fast mode and low power mode selection by pad optional (LPMB pin).
- Auro calibration feature for life. The re-calibration period is about 4.0sec when the key has not been touch.
- Provides direct mode or toggle mode, CMOS output, or open-drain output. active high or active low by option (TOG/AHLF/OD pin)
Specifications
- Operating voltage：2.4V~5.5V
- Stand-by current At 3V, 2.5uA
- On-Board Power Indicator LED
- Operates In 8 Or 16 Channel Mode
- Output Can Configured Be Active High Or Low
- Output Mode Can Be Configured To Toggle Or Momentary
- 0.5 Second Startup Calibration Delay
- Configurable Output Mode
- 8 Key or 16 key modes
- Separate outputs to 8 keys in 8 key mode
- PCB Size At 49.3 x 64.5mm
Pinouts of TTP229
| Pin Name | Description |
| Out 1 | Direct Output pin |
| Out 2 | Direct Output pin |
| Out 3 | Direct Output pin |
| Out 4 | Direct Output pin |
| Out 5 | Direct Output pin |
| Out 6 | Direct Output pin |
| Out 7 | Direct Output pin |
| Out 8 | Direct Output pin |
| SDO | The 8-Bit serial data shows the status of the touch buttons 1-8. |
| SCL | Serial clock pin |
| Vcc | Power pin typically requires 5V |
| GND | The ground pin needs to be connected to the ground of the system. |
Applications of TTP229 Module
Consumer products
Because of its great sensing ability and keypads, we can utilize the sensor in various consumer products that require keypads and works on a single human touch.
Matrix Keypad
A matrix keypad is a popular interface component for embedded systems. The keypad gets designed by multiplexing push buttons into rows and columns, which serve as a matrix of push buttons. Each push-button is related to only one row and only one column. TTP229 Module can serve as a matrix keypad.
