Microchip MCP4013T-103E/CH 7-Bit Digital Potentiometer: Features and Application Circuits

The Microchip MCP4013T-103E/CH is a compact, 7-bit resolution digital potentiometer (digipot) from Microchip Technology, offering a simple yet effective digital alternative to traditional mechanical potentiometers and trimmers. As a member of the MCP40D1x series, this device is designed for applications requiring programmable resistance changes via a digital interface. It features a standard I²C-compatible serial interface for easy communication with microcontrollers and other digital circuits.

This digipot provides 128 wiper positions (7-bit), with a nominal end-to-end resistance of 10 kΩ. It operates from a single power supply ranging from 1.8V to 5.5V, making it suitable for both 3.3V and 5V systems. The MCP4013T-103E/CH is offered in a space-saving SOT-23-6 package, ideal for compact PCB designs. A key feature is its non-volatile memory (EEPROM), which allows the wiper position to be stored and recalled upon power-up, ensuring the device resumes operation at the last set value without requiring reprogramming.

The MCP4013T-103E/CH is commonly used for system calibration, parameter adjustments, and signal conditioning. Typical applications include:

- Volume control in audio systems, where it digitally adjusts audio signal levels.

- LCD display contrast or brightness adjustment in embedded systems.

- Programmable gain amplification in op-amp circuits by replacing fixed resistors with the digipot.

- Sensor calibration and trimming, where manual adjustment is impractical.

A basic application circuit for programmable gain in a non-inverting amplifier configuration is shown below. The digipot replaces the traditional feedback resistor network, allowing digital control of the amplifier’s gain.

```

Vdd ---[MCP4013T-103E/CH]--- Vss

| (Wiper)

|

+--- To Inverting Input of Op-Amp

```

In this setup, the wiper output is connected to the inverting input of the op-amp, while one end terminal (e.g., Terminal A) is connected to the op-amp output, forming a feedback path. The gain can be digitally adjusted by changing the wiper position through the I²C interface.

Another common circuit is for digital volume control, where the digipot is placed between the audio source and amplifier input. The wiper taps the audio signal, and its position sets the attenuation level.

ICGOOODFIND: The MCP4013T-103E/CH is a versatile and cost-effective digital potentiometer, combining ease of use with non-volatile memory. Its small form factor, low power operation, and simple digital interface make it an excellent choice for modern electronic designs requiring reliable and programmable resistance adjustments.

Keywords: Digital Potentiometer, I²C Interface, Non-Volatile Memory, Programmable Gain, Signal Conditioning