Skip to main content

BS801B Touch Key Controller

BS801B is a touch key controller with single key input. It is a very useful alternative to standard physical electronic or mechanical switches with a very low component count. It can detect human body contact using an external touch sensor.


The controller uses internal circuitry specially designed for power-related noise rejection that effects in the reduction of false detection. Thus making it reliable for operations in adverse environmental conditions as well as in industrial applications. The sensor enables auto-calibration, hence there is no need to calibrate it manually.


Pin Description of BS801B

Pin Number

Pin Name




Touch output pin



Negative power supply Pin



Touch key input



Touch key reference capacitor input



Negative power supply or Ground



Output key type selection


The pinout is shown in the below image- 

BS801B Pin Diagram


Features and Specification of BS801B

  • Ultra-low standby current: 1.5uA at 3V
  • Operating Voltage (VCC = 2.2V - 5.5V)
  • Auto-calibration
  • High-reliability touch detections
  • Output type selection: Level-hold or Toggle
  • One-Key wake-up mode


Note: Complete technical details can be found in the BS801B Datasheet, linked at the bottom of this page.


Alternative for BS801B

The following are the equivalents for BS801B-

1.    TTP223

2.    TTP226

3.    AT24QT1010


BS801B Touch Controller IC Overview

The BS801B touch controller is equipped with a single touch detection feature with the output type selection pin. It offers a wide operating voltage from 2.2V to 5.5V. BS801B offers LHF pins that can be set as open or low externally and the output can be selected as Level-Hold output or toggle type.


The touch controller sensitivity can also be adjusted by using an external capacitor ranging from 0pF to 10pF. Higher value capacitance results in higher sensitivity.


Overall, BS801B offers an easy and cost-effective implementation of touch sensor capabilities in various applications.


How to Use BS801B Touch Key Controller IC

The below BS801B Application Diagram is showing the standard connection of the BS801B controller.

BS801B Application Diagram

The LHF pin can be open or connected with the ground to set it low. However, the logic level of the LHF pin mustn't change state after power on.


Applications of BS801B

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


2D Model of BS801B

The dimensions of BS801B is given below to help you with selecting the PCB footprint for BS801B.

2D Model of BS801B

BS801B Dimensions

Component Datasheet

Related Post

Join 20K+subscribers

We will never spam you.

* indicates required

Be a part of our ever growing community.