HOW DOES IT WORK?

POT 4 Click is based on the PRS11R-425F-S103B1, a high-quality rotary 10k potentiometer from Bourns providing very accurate voltage output. The PDB081-P10-103B1 features a small form factor, offers a push-on momentary switch, a flatted shaft style, and a wide operating temperature range, withstanding 50V maximum voltage. Typical applications include consumer white goods, test and measurement equipment, communications and laboratory equipment, and other applications requiring an analog or digitized control voltage.

The output of the potentiometer is brought to the non-inverting input of the OPA344, a rail-to-rail operational amplifier from Texas Instruments, used as a stable unity gain buffer, providing a constant input and output impedance. Without a buffer, the variable impedance would affect the reference voltage. Therefore, the OPA344 ensures good stability of the circuit.

A buffered signal can be converted to a digital value using the MCP3221, a successive approximation A/D converter with a 12-bit resolution from Microchip using a 2-wire I2C compatible interface, or can be sent directly to an analog pin of the mikroBUS™ socket labeled as AN. The selection can be performed by using an onboard SMD switch labeled as VIN SEL, placing it in an appropriate position marked as AN or ADC. Noting that the PRS11R-425F-S103B1 has an optional push momentary switch, this Click board™ also has an interrupt that will signal to users when this feature is used.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. The Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS