MCP40D18T-503E/LT

Overview

The MCP40D18T-503E/LT is a single-channel digital potentiometer featuring a 7-bit resistor network with 128 adjustable steps. It utilizes an I²C serial control interface and volatile RAM memory to store wiper settings. The device supports both potentiometer and rheostat configurations, offering end-to-end resistance options of 5 kΩ, 10 kΩ, 50 kΩ, or 100 kΩ. It operates within a supply voltage range of 1.8V to 5.5V and includes power-on reset protection that defaults the wiper to mid-scale. The component is housed in a compact SC70-6 surface-mount package.

Feature Summary

• I²C Serial Interface: Supports SMBus 2.0 Write Byte/Word and Read Byte/Word protocol formats.
• Dual Configuration: Operates as either a potentiometer or rheostat with zero-scale to full-scale wiper operation.
• Low Power Consumption: Features typical static current of 2.5 µA and low wiper resistance of 100 Ω (typical).
• Protection Features: Includes Brown-out Reset (BOR) protection at 1.5V typical and Power-on Reset (POR) for mid-scale initialization.

Applications

• Amplifier Gain Control and Offset Adjustment
• Sensor Calibration (Pressure, Temperature, Position, Optical, and Chemical)
• Set Point or Offset Trimming
• RF Amplifier Biasing
• LCD Brightness and Contrast Adjustment

Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and temperature range. Ensure the I²C address configuration matches the system design, as this model supports specific standard addresses. Confirm RoHS compliance status if required by assembly specifications.

Selection Notes

Select this component when a volatile memory digital potentiometer with I²C control is required. The 7-bit resolution provides 128 distinct tap positions suitable for precision trimming. Verify that the application voltage falls within the 1.8V to 5.5V operating range and that the SC70-6 package dimensions fit the PCB layout constraints.

Part Context

This part belongs to the MCP40D17/18/19 family of 7-bit digital potentiometers manufactured by Microchip Technology. The 'D' series distinguishes these devices by their support for the I²C Command Code feature, allowing for higher data throughput compared to simplified command formats found in other variants like the MCP4018.

Replacement Considerations

The MCP4018T-503E/LTY is a functional equivalent within the same family but uses a simplified I²C command format. When substituting, verify that the host controller software supports the specific command code structure required by the replacement part.