Analog Devices Inc./Maxim Integrated DS1867E-50

Overview

DS1867E-50 from Maxim Integrated (now Analog Devices) is a dual nonvolatile digital potentiometer with EEPROM, featuring two 256-position wiper settings, 50 kΩ end-to-end resistance per potentiometer, ±0.75 LSB absolute linearity, and operation from single 5V supply. It serves as a precision programmable resistor in gain/attenuation control loops for analog signal conditioning circuits.

For engineers reviewing the DS1867E-50 datasheet, DS1867E-50 pinout, DS1867E-50 application, or DS1867E-50 equivalent, this page delivers verified pin functions, stacked/cascaded configuration details, EEPROM endurance (25,000 writes), wiper nonvolatility behavior, and real-world use cases in inverting amplifiers and fixed-gain attenuators.

Technical Context

The DS1867E-50 implements a 3-wire serial interface (RST, CLK, DQ) with active-high reset and edge-triggered data latching on CLK rising edge. Its internal 17-bit I/O shift register stores two 8-bit wiper positions plus a stack-select bit, enabling either independent or series-connected (stacked) operation of the two potentiometers.

Wiper position retention relies on EEPROM shadow memory updated during controlled power-down (VCC falling below 4.5 V), requiring ≥4 ms between 4.5 V and 3.0 V to guarantee storage. Cascading uses COUT-to-DQ daisy-chaining with 70 ns propagation delay per device, supporting multi-unit control over one bus.

Key Specifications

Pinout & Package

DS1867E-50 is packaged in 16-pin SOIC (300-mil) with exposed pad not connected. Pin functions are validated per Maxim Integrated DS1867 datasheet Rev 0B (102199).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual digital potentiometer applications.

Compared with AD5232BRUZ10 and MCP42050-I/P, the DS1867E-50 uniquely combines 50 kΩ resistance, built-in EEPROM, 3-wire simplicity, and hardware-supported cascading-making it optimal for space-constrained, multi-pot industrial calibrators needing zero-bom-addition nonvolatility.

Availability

DS1867E-50 is available at Aetrix Electronics and suitable for industrial calibration modules, telecom line card biasing, analog sensor signal conditioning, and embedded instrumentation requiring stable component supply across extended product lifecycles.

Supply support for DS1867E-50 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated, now part of Analog Devices, designs precision analog and mixed-signal ICs for industrial, automotive, and communications markets.

The DS1867E-50 belongs to Maxim's digital potentiometer family engineered for replacing mechanical trimmers in automated calibration, gain control, and bias setting applications where EEPROM-backed repeatability is essential.

FAQ

What is the resistance tolerance of the DS1867E-50?

The DS1867E-50 has a ±20% end-to-end resistance tolerance at 25°C. This means the actual measured resistance between H0–L0 or H1–L1 terminals will fall within 40 kΩ to 60 kΩ under nominal conditions. The tolerance applies to the total potentiometer element and does not affect wiper linearity or step resolution. For precision gain-setting applications, system-level calibration compensates for this initial variance, and the DS1867E-50's nonvolatile storage preserves calibrated wiper positions across power cycles.

Does the DS1867E-50 require an external pull-up resistor on the DQ line?

No, the DS1867E-50 does not require an external pull-up on the DQ line during normal write operations. Its DQ pin is driven actively during data input. However, when implementing read-back via the COUT feedback loop, a 2–10 kΩ isolation resistor must connect COUT to DQ to enable circular shifting of stored wiper data - this resistor serves as a passive level translator, not a pull-up. The DS1867E-50's internal logic handles drive strength and signal integrity without additional biasing components.

Can the DS1867E-50 operate from a 3.3 V supply?

No, the DS1867E-50 is specified only for 4.5 V to 5.5 V operation. Its absolute maximum ratings and DC operating conditions do not include 3.3 V compatibility. Attempting to power the DS1867E-50 at 3.3 V may result in undefined logic states, failed EEPROM writes, or incomplete wiper position loading. For 3.3 V systems, consider alternatives such as the AD5231BRUZ10 or MCP42050-I/P, both rated down to 2.7 V and offering similar dual-pot functionality with SPI interface.

How does the DS1867E-50 handle power-down wiper storage?

The DS1867E-50 automatically initiates EEPROM storage when VCC falls below 4.5 V, provided the voltage remains above 3.0 V for ≥4 ms (tPU1). During this window, the contents of the 17-bit I/O shift register - including both wiper positions and the stack-select bit - are transferred to EEPROM shadow memory. This process is fully transparent and requires no host intervention. If power drops too rapidly (e.g., <4 ms), wiper data may not be saved, causing the DS1867E-50 to restore the last successfully stored value on next power-up.

What is the maximum number of DS1867E-50 devices that can be cascaded?

The DS1867E-50 datasheet does not specify a hard upper limit on cascading, but practical constraints arise from timing and signal integrity. Each device adds 70 ns propagation delay on COUT, and total CLK setup/hold margins must be maintained across the chain. For reliable operation at 10 MHz CLK, chains exceeding 16 devices risk violating tDC (30 ns min) and tCDH (10 ns min). Most validated designs use 4–8 DS1867E-50 units per bus. Longer chains require reduced CLK frequency or buffered COUT routing to preserve signal fidelity.