Analog Devices Inc./Maxim Integrated MAX5424ETA

Overview

MAX5424ETA from Maxim Integrated is a 256-tap, nonvolatile digital potentiometer with 200kΩ end-to-end resistance, SPI-compatible 3-wire interface (up to 5MHz), ±0.5 LSB INL/DNL in voltage-divider mode, and 5ppm/°C ratiometric temperature coefficient-designed for precision programmable gain amplifiers and LCD contrast control where stable resistance over temperature is critical.

For engineers reviewing the MAX5424ETA datasheet, MAX5424ETA pinout, MAX5424ETA application, or MAX5424ETA equivalent, key selection criteria include its 200kΩ resistance value, TDFN-EP 8-pin package, nonvolatile EEPROM wiper storage, low 500nA standby current, and guaranteed monotonicity across -40°C to +85°C operation.

Technical Context

The MAX5424ETA implements a 255-element resistor string with 256 accessible tap points between H and L terminals, supporting both voltage-divider and variable-resistor configurations. Its BiCMOS process enables precise ratiometric TC of 5ppm/°C and end-to-end TC of 35ppm/°C-critical for low-drift analog signal conditioning.

Digital control uses a write-only 3-wire SPI interface with command encoding (C1/C0 bits) for wiper register writes, NV register writes, and copy operations. Power-on reset loads the wiper position from nonvolatile memory within 10µs, and standby mode draws only 0.5µA typical supply current.

Key Specifications

Pinout & Package

MAX5424ETA is housed in an 8-pin TDFN-EP package (3mm × 3mm × 0.8mm) with exposed pad (EP), rated for -40°C to +85°C operation. The EP is not internally connected and may be left floating or tied to GND for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5242BRUZ200 and MCP41HV50-204E/SN, the MAX5424ETA uniquely delivers SPI compatibility with ultra-low 5ppm/°C ratiometric tempco and guaranteed monotonicity-making it optimal for precision voltage-scaling and gain-control applications where temperature-induced drift must be minimized.

Availability

MAX5424ETA is available at Aetrix Electronics and suitable for LCD contrast control, programmable gain amplifiers, adjustable voltage references, and programmable filter designs requiring stable component supply, long-term calibration retention, and industrial temperature operation.

Supply support for MAX5424ETA 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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and communications markets.

The MAX5422/MAX5423/MAX5424 family was designed specifically for replacing mechanical potentiometers in precision analog control loops-emphasizing nonvolatile storage, low tempco, and robust digital interface integrity under extended temperature operation.

FAQ

What is the maximum allowable voltage across the H and L terminals of the MAX5424ETA?

The MAX5424ETA specifies absolute maximum ratings of VDD to GND = -0.3V to +6.0V and all other pins to GND = -0.3V to (VDD + 0.3V). Since H and L are analog terminals referenced to GND, their voltage must remain within GND and VDD. Therefore, the maximum voltage across H and L is limited to the supply voltage range: +2.7V to +5.25V. Exceeding this risks permanent damage, as confirmed in the Absolute Maximum Ratings table.

Does the MAX5424ETA support true bidirectional current flow through the wiper terminal?

Yes-the MAX5424ETA allows bidirectional current flow through the wiper (W), high (H), and low (L) terminals, as explicitly stated in the Pin Description: "The voltage at H can be greater than or less than the voltage at L. Current can flow into or out of H." This enables flexible configuration as either a voltage divider or variable resistor in AC-coupled or dual-supply circuits, provided all terminal voltages stay within GND and VDD.

How many times can the nonvolatile memory of the MAX5424ETA be written before failure?

The nonvolatile EEPROM in the MAX5424ETA is rated for 200,000 store cycles at +85°C, as specified in the Electrical Characteristics table under "NONVOLATILE MEMORY RELIABILITY." This endurance rating applies to write operations that store the wiper position to NV memory (via "Write NV Register" or "Copy Wiper to NV" commands), and is validated across the full operating temperature range.

Can the MAX5424ETA be used in variable-resistor mode with the H terminal left unconnected?

Yes-per the Detailed Description, the MAX5424ETA supports variable-resistor mode with H unconnected and L tied to GND. In this configuration, the wiper (W) and L form a two-terminal adjustable resistor. The datasheet confirms DNL and INL are characterized under this condition (Note 2), and guarantees monotonicity for the MAX5424 at VDD = 2.7V with 10µA source current-validating safe use in this topology.

What is the typical wiper resistance of the MAX5424ETA, and how does it vary with tap position?

The MAX5424ETA has a typical wiper resistance (R_W) of 500Ω, with a guaranteed range of 325Ω to 675Ω (Electrical Characteristics table). Per Typical Operating Characteristics (Figure MAX5422 toc03), R_W varies by <±5% across tap positions at VDD = 2.7V, remaining stable and predictable-critical for minimizing insertion error in series-adjustment applications like gain-setting resistors.