KY-051

This level shifter converts digital signals from one voltage down to another or up. A total of four channels are available on which conversions can be made.

Nowadays there are a lot of microcontroller systems which operate in different voltage ranges: For example, the inputs and outputs of older systems such as the Arduino, based on an Atmega controller, operate at 5 V levels. Newer devices, such as the Raspberry-Pi computer based on an ARM controller, operate at a 3.3 V voltage level.

However, if communication between two systems with different voltage levels is desired, the voltage level must be "shifted", i.e. adjusted. If no adjustment is made, the excess voltage must be consumed elsewhere (e.g. in the form of heat). Depending on the system, this can lead to permanent damage to the device.

Pin assignment

The pin assignment is printed on the module board.

The signals at the inputs/outputs A1-A4, as well as B1-B4 are shifted to the respective voltage level (VCCa -> A1-A4 | VCCb -> B1-B4).

Example:

Arduino output -> Digital [ON] = 5V @ B1 >>>>>>> 3.3V @ A1 -> Raspberry Pi input

Additional software or code is not required for operation; the module works autonomously.

Please note that VCCb must be greater than / equal to VCCa (example VCCb = 5V - VCCa = 3.3V)

Example connection assignment between Arduino and Raspberry Pi:

Pin assignment Arduino:

Arduino Sensor
5 V Vccb
Pin 3 B1
Pin 4 B2
Pin 5 B3
Pin 6 B4
Ground GND

Pin assignment Raspberry Pi

Raspberry Pi Sensor
3.3 V [pin 1] Vcca
GPIO 18 [pin 12] A1
GPIO 3 / SCL [Pin 5] A2
GPIO 2 / SDA [Pin 3] A3
GPIO 11 [pin 8] A4
Ground [pin 6] GND

Please make sure that both systems are connected to the same GND (ground) - OE does not have to be connected with this module.

Example connection assignment between Arduino and Micro:Bit:

Pin assignment Arduino:

Arduino Sensor
5 V Vccb
Pin 3 B1
Pin 4 B2
Pin 5 B3
Pin 6 B4
Ground GND

Pin assignment Raspberry Pi

Micro: bit Sensor
3.3 V [pin 3V] Vcca
P0 [pin 0] A1
P1 [pin 1] A2
P2 [pin 2] A3
P8 [pin 8] A4
Ground [pin GND] GND

Please make sure that both systems are connected to the same GND (ground) - OE does not have to be connected to this module.