MCP40D18T-502E/LTY

Overview

The MCP40D18T-502E/LTY is a single-channel digital potentiometer IC manufactured by Microchip Technology. It features a 7-bit resistor network providing 128 tap positions and operates in a potentiometer configuration. The device utilizes an I2C serial interface with command code support and SMBus 2.0 compatibility. Electrical specifications include a nominal resistance (RAB) of 5 kΩ, a typical wiper resistance of 100 Ω, and a supply voltage range of 1.8 V to 5.5 V. Static current consumption is typically 2.5 µA. The component is housed in a compact SC70-6 surface-mount package and supports an extended operating temperature range from -40°C to +125°C.

Feature Summary

• 7-bit resolution with 128 discrete tap steps for precise resistance adjustment
• I2C protocol interface supporting SMBus 2.0 Write Byte/Word and Read Byte/Word formats
• Volatile RAM memory retaining wiper settings only during power
• Power-on reset defaults the wiper to mid-scale position

Applications

• Amplifier gain control and offset adjustment circuits
• Sensor calibration for pressure, temperature, and optical sensors
• Set point or offset trimming in electronic systems
• Replacement for mechanical trim potentiometers in cost-sensitive designs
• LCD brightness and contrast adjustment modules

Procurement Notes

Verify the specific ordering suffix 'LTY' against the manufacturer's datasheet to confirm packaging details and tape-and-reel quantities. Ensure the design accounts for the volatile nature of the internal RAM, as wiper settings will be lost upon power loss. Confirm that the I2C address '0111110' matches the system bus requirements.

Selection Notes

Select this component when a single-channel potentiometer configuration is required rather than a rheostat. The MCP40D18 differs from the MCP40D17 and MCP40D19 primarily in its terminal configuration and available I2C addresses. Verify that the 5 kΩ resistance value aligns with the target circuit impedance and that the 1.8 V minimum supply voltage meets the system's low-power constraints.

Part Context

This part belongs to the MCP40D17/18/19 family of 7-bit digital potentiometers. While the MCP40D17 and MCP40D19 are configured as rheostats, the MCP40D18 is specifically designed for potentiometer applications. All three devices share similar electrical characteristics, including the I2C interface and low static current consumption, but differ in pinout and terminal connectivity.

Replacement Considerations

The MCP4018T-502E/LTY is a parameter-equivalent alternative within the same family. Both devices offer identical 7-bit resolution, 5 kΩ resistance, and I2C interface capabilities in the SC70-6 package.