Created on: 6 December 2017
Pinout of the knock sensor module from the 37 in 1 sensor kit for Arduino from Geekcreit, Elegoo, Elektor and others.
The knock sensor module detects a knock or tap. If the knock is hard enough, the sensor switch will briefly close, allowing the knock to be detected by a circuit or device such as an Arduino. A built in 10k resistor on the module can be used as a pull-up or pull-down resistor.
This knock sensor module is found in the 37 in 1 sensor kit that is branded under several different names and found in many online shops.
There appear to be two different configurations for this module, depending on which kit they come from. The difference is which pins the 10k resistor is connected to on the module.
Before continuing, check your module with a multimeter to make sure which configuration your module is using. Both configurations are shown in the pinout images below.
Note one difference in the below images of the module – on the first module, the text R1 is silk-screened to the left of the board and is upside down. In the second image, R1 is silk-screened at the right of the board.
The image below shows the pinout for the Geekcreit knock sensor module. The knock sensor switch connects between the outer two pins of the module. A 10k resistor connects from the middle pin to the right pin as can be seen in the circuit diagram of the module at the right of the image.
It is suggested to use a multimeter to check whether this is indeed the configuration of your module, or if your module uses the configuration in the next pinout image below.
In the image below, an alternate configuration of the knock sensor module can be seen. The 10k resistor connects between the middle pin and the left pin of the module.
There are two ways to wire the the knock sensor module as shown in the circuit diagrams below. In the left circuit, the module's resistor is used as a pull-down resistor. In the right circuit, the resistor is used as a pull-up resistor.
The right pin (marked -) in both circuits is used as the sense pin to detect the Knock. When using an Arduino, the sense pin can be connected to an Arduino input pin to detect when the switch closes.
These circuits work as described above, but are for the modules with the 10k resistor between the left and middle pins.
The knock sensor module tutorial shows basic use and testing of the knock sensor module with Arduino.