MCP4561-503E/MS

Digital Potentiometers Overview

The MCP4561-503E/MS is a single-channel, nonvolatile digital potentiometer from Microchip Technology. It features an 8-bit resistor network providing 257 discrete taps and a nominal resistance of 50 kΩ (indicated by the '503' suffix). The device operates on a supply voltage ranging from 2.7V to 5.5V and communicates via a standard I²C serial interface. Key specifications include a typical wiper resistance of 75 Ω, a temperature coefficient of 150 ppm/°C across the extended operating range (-40°C to +125°C), and integrated WiperLock™ technology for securing calibration settings in EEPROM.

Digital Potentiometers Feature Summary

• Nonvolatile Memory with WiperLock™ Technology: Automatically recalls saved wiper settings upon power-up and allows locking specific calibration data in 10 general-purpose memory locations.
• I²C Serial Interface: Supports Standard Mode (100 kHz), Fast Mode (400 kHz), and High-Speed modes (up to 3.4 MHz) for efficient communication.
• High-Voltage Tolerant Inputs: Digital input pins (HVC/A0, SDA, SCL, WP) tolerate voltages up to 12.5V, enabling direct interfacing with higher voltage logic systems.
• Flexible Configuration: Operates as a potentiometer or rheostat with zero-scale to full-scale wiper movement and includes a terminal disconnect feature via the TCON register.

Digital Potentiometers Applications

• Precision gain control in instrumentation amplifiers
• Voltage reference trimming and offset adjustment
• Audio volume control and tone shaping circuits
• Calibration of sensor signal conditioning paths

Digital Potentiometers Procurement Notes

Verify the package marking and datasheet revision when sourcing. Confirm that the application circuit respects the absolute maximum ratings, particularly the 12.5V tolerance on digital inputs versus the VDD limit. Ensure the I²C bus speed matches the device's specified AC characteristics for the chosen supply voltage.

Digital Potentiometers Selection Notes

Select this component over volatile variants (e.g., MCP4531) if power-down retention of the resistance setting is required. Choose the 50kΩ version for applications requiring higher impedance levels compared to the 5kΩ or 10kΩ options. Verify that the 2.7V minimum supply voltage aligns with the system's lowest operating voltage, as operation below this threshold is not guaranteed for analog characteristics.

Digital Potentiometers Part Context

This part belongs to the MCP454X/456X family of 7/8-bit digital potentiometers. The '61' designation indicates a single-potentiometer configuration with nonvolatile memory and 8-bit resolution. It shares the same pinout and core architecture as the dual-channel MCP4661 but contains only one resistor network within the MSOP-8 package.

Digital Potentiometers Replacement Considerations

For direct functional replacement, consider the MCP4561T-503E/MS (tape and reel variant) or other resistors within the MCP456X series with matching resistance values. Cross-family replacements like the MCP4541 require verification of nonvolatile memory support and voltage range compatibility.

Digital Potentiometers FAQ

What is the function of the WiperLock™ technology?

WiperLock™ technology allows the user to save the current wiper position into the internal EEPROM and lock it against further changes. This ensures that critical calibration settings are retained after power cycles and protected from accidental modification.

Can the MCP4561 operate with a 1.8V supply?

No. While some devices in the broader family support 1.8V, the MCP4561 specifies an operating voltage range of 2.7V to 5.5V for its analog characteristics. Operation at 1.8V is not supported for this specific model.

How does the device handle high-voltage signals on the digital pins?

The digital input pins, including HVC/A0, SDA, SCL, and WP, are high-voltage tolerant and can withstand voltages up to 12.5V. This allows them to be driven by logic levels higher than the VDD supply voltage.