TTP223 Single Channel Touch Detector IC

TTP223 is a single channel touch detector IC that could be used as a 1 touch key driver. It is a useful interface when replaced with a traditional button key. It has a low power consumption with a wide range of operating voltage. It has an auto calibration feature for life and it has a re-calibration period of about 4.0 seconds. The sensitivity can be adjusted using an external capacitor of 0 to 50 pF.

 

Pin Description of TTP223

Pin Number	Pin Name	Description
1	Q	CMOS output pin
2	VSS	Power Supply negative pin
3	I	Input of the Sensor Port
4	AHLB	Output active high or low
5	VDD	Power Supply Positive pin
6	TOG	Output type option pin

 

The pinout is shown in the below image-

 

 

Features and Specification of TTP223

• Single channel touch key sensing
• 2.0V - 5.0V Operating Voltage
• Operating current 1.5uA typically. Maximum operating current 3.0uA at Low power mode.
• Response time - 220ms at low power mode.
• Adjustable sensitivity using external capacitor (0-50 pF)
• Stable touch detection of human body
• All output modes can be configurable for high or active low by pad options.
• Direct mode and Toggle mode selection pin available

 

Note: Complete technical details can be found in the TTP223 Datasheet linked at the bottom of this page.

 

Alternative product of TTP223

The other alternatives for TTP223 are listed below.

1. CAP1203
2. TTP226
3. TTP229

 

TTP223 Touch controller IC - Overview

The TTP223 touch controller is the exact non-contact alternative to traditional button switches. The IC uses an onboard sense pad that uses copper trace as a touch element and the touch sensitivity can be configured using an additional external capacitor ranging from 0 to 50pF.

 

There are two pins, AHLB and TOG that could be used to configure the output state either high or low or toggle mode enable option. The configurable output is set by those two pins as per the below chart.

It is available in SMD, SOT23-6L package.

 

Interfacing Diagram and How to Use the TTP223

The below image is showing standard 2.2-5V interfacing of the touch sensor. It requires basic components followed by a sense pad.

As we can see, the sense pad is connected to the Input pin and two-slide switches are given to select the configuration of TOG and AHLB. The C1 can be configurable as per the required sensitivity.

 

Follow the below guidelines for PCB design related purposes-

1. Place the Sense pad as close as possible to the IC
2. Do not use mechanical enclosure
3. Use proper filter and bypass capacitor to reduce noises or ripple in the input supply
4. Place the capacitor C2 as close as possible.
5. Use an X7R or NPO rated capacitor for better accuracy over a wide temperature.

 

Applications of TTP223

• Appliances control
• Wide range of consumer products
• Replacement of button switches

 

2D Model of TTP223

The dimensions of TTP223 are given below to help you with selecting the PCB footprint for TTP223.