DS1855E-050+

Digital Potentiometers Overview

The DS1855E-050+ is a dual nonvolatile digital potentiometer and secure memory device from Analog Devices. It integrates one 10kΩ, 100-position linear taper potentiometer and one 50kΩ, 256-position linear taper potentiometer, alongside 256 bytes of EEPROM memory. The component operates on a 2-wire serial interface (SDA/SCL) with supply voltages ranging from 2.7V to 5.5V. It features hardware write protection via the WP pin and software-controlled locking for specific memory blocks. The device supports industrial temperature ranges (-40°C to +85°C) and includes nonvolatile wiper storage to retain settings across power cycles.

Digital Potentiometers Feature Summary

• Dual linear taper potentiometers: Pot 0 (10kΩ, 100 positions) and Pot 1 (50kΩ, 256 positions).
• 256-byte EEPROM with dedicated registers for wiper position storage at addresses F8h and F9h.
• Hardware write-protect pin (WP) and software-configurable lock bytes for data security.
• Standard 2-wire serial interface supporting standard (100kHz) and fast (400kHz) modes.

Digital Potentiometers Applications

• Bias voltage and current setting in control applications.
• System configuration and calibration data storage.
• Multi-device bus systems requiring addressable potentiometer control.

Digital Potentiometers Procurement Notes

Verify the ordering suffix '+P' or absence thereof against the manufacturer's current datasheet revision to confirm lead-free status and RoHS compliance. Ensure the package type matches the required footprint, as the DS1855 family offers TSSOP, CSBGA, and flip-chip options. Confirm that the '-050' variant specifically provides the 50kΩ second potentiometer, as other suffixes like '-010' or '-020' have different resistance values.

Digital Potentiometers Selection Notes

Select the DS1855E-050+ when a combination of a low-resistance 100-step pot and a higher-resistance 256-step pot is required. The 50kΩ value of Potentiometer 1 distinguishes this model from the -010, -020, and -100 variants. Consider the 256-byte EEPROM capacity for storing calibration data alongside wiper positions. Ensure the application requires nonvolatile retention of wiper settings upon power-up, which is a key feature of this device compared to volatile digital pots.

Digital Potentiometers Part Context

The DS1855 is an upgrade to the DS1845, adding software write protect capabilities. It belongs to the Maxim Integrated (now Analog Devices) line of nonvolatile digital potentiometers. The 'E' indicates an extended industrial temperature range (-40°C to +85°C), while the '+' denotes lead-free/RoHS compliant packaging. This part is designed for applications needing persistent adjustment of analog parameters without external nonvolatile memory components.

Digital Potentiometers Replacement Considerations

Direct replacements include other DS1855 variants with different resistor values (DS1855-010, DS1855-020, DS1855-100) if resistance values are flexible. The DS1845 is a compatible predecessor but lacks the software write protect feature. Verify pin compatibility and EEPROM size when substituting with other digital potentiometer families.