Analog Devices Inc./Maxim Integrated MAX5437EUD+T

Overview

The MAX5437EUD+T from Maxim Integrated is a 128-tap, ±15V high-voltage digital potentiometer in a 14-pin TSSOP package, featuring integrated uncommitted high-voltage amplifier, 50kΩ end-to-end resistance, 35ppm/°C end-to-end tempco, and SPI-compatible serial interface. It replaces mechanical potentiometers in precision analog control circuits requiring stable gain or bias adjustment under wide supply ranges.

For engineers reviewing the MAX5437EUD+T datasheet, MAX5437EUD+T pinout, MAX5437EUD+T application, or MAX5437EUD+T equivalent, this device is selected for high-voltage programmable gain amplifiers, LCD contrast control with dual-supply operation, and low-drift voltage-divider configurations where analog supply separation (VDD–VSS ≥ 9V) and midscale power-on reset are critical design requirements.

Technical Context

The MAX5437EUD+T implements a 7-bit serial interface with chip-select–driven latch timing, supporting SPI/QSPI/MICROWIRE protocols. Its resistor string operates independently from digital logic: VDD/VSS supplies (±5V to ±15V or +10V to +30V) power the analog path, while VCC (+2.7V to +5.25V) powers the digital core - enabling true supply isolation.

It integrates a rail-to-rail input/output amplifier with 100kHz unity-gain bandwidth, ±6mV input offset, and output compliance of VSS+1V to VDD−1V at ±5mA load. The amplifier shares no internal signal path with the potentiometer terminals but is co-packaged to reduce board space in closed-loop gain control designs.

Key Specifications

Pinout & Package

MAX5437EUD+T is housed in a 14-pin TSSOP package (4.4mm body width, 0.65mm pitch), specified per JEDEC MO-153, with exposed pad not electrically connected. Thermal performance supports 727mW max dissipation at +70°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5292BRUZ-20 and DS1804Z-100, the MAX5437EUD+T uniquely combines ±15V analog operation, integrated amplifier, and 128-tap resolution - making it optimal for high-voltage, space-constrained gain/bias control where volatile wiper state is acceptable.

Availability

MAX5437EUD+T is available at Aetrix Electronics and suitable for LCD biasing, programmable gain amplifiers, mechanical potentiometer replacement, precision voltage scaling, and high-voltage sensor interface applications requiring stable component supply and guaranteed extended-temperature performance.

Supply support for MAX5437EUD+T 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, communications, and consumer applications.

The MAX5436–MAX5439 family was designed for high-voltage, low-drift digital potentiometer applications demanding supply flexibility, temperature stability, and board-space efficiency - particularly in LCD systems, data acquisition, and programmable analog signal conditioning.

FAQ

What supply voltages does the MAX5437EUD+T require?

The MAX5437EUD+T requires three independent supplies: VDD and VSS for the analog resistor string and amplifier (VDD–VSS = 9V to 31.5V, e.g., ±15V or +30V), and VCC for digital logic (+2.7V to +5.25V). These domains are isolated - VCC need not track VDD/VSS, enabling mixed-supply system integration without level shifters. All supplies must be present for full functionality.

Does the MAX5437EUD+T retain wiper position after power cycling?

No, the MAX5437EUD+T does not include nonvolatile memory. Upon power-up, its wiper resets to midscale (position 64) via internal power-on reset circuitry. To restore a specific setting, the host microcontroller must retransmit the desired 7-bit code via SPI after power stabilization. This behavior is confirmed in the Electrical Characteristics table under "Power-On Reset".

Can the integrated amplifier in the MAX5437EUD+T operate independently of the potentiometer?

Yes, the amplifier in the MAX5437EUD+T is fully independent: its IN+, IN−, and OUT pins are electrically isolated from the H, W, and L resistor terminals. It can be used as a standalone high-voltage op-amp (e.g., for signal buffering) while the potentiometer functions separately as a voltage divider or variable resistor - or both can be used together in gain-control topologies as shown in Figure 4 of the MAX5437EUD+T datasheet.

What is the maximum analog signal frequency supported at the wiper terminal of the MAX5437EUD+T?

At midscale with 50kΩ end-to-end resistance and 20pF wiper capacitance, the MAX5437EUD+T wiper exhibits a −3dB bandwidth of 400kHz in voltage-divider mode. This is measured under standard conditions (VH = 1.5V_P-P, CWIPER = 20pF) and represents the usable small-signal AC response limit before significant attenuation occurs - sufficient for DC and low-frequency analog control, but not RF or high-speed signal routing.

How does the MAX5437EUD+T handle power-up sequencing between VDD, VSS, and VCC?

The MAX5437EUD+T is designed for robust power-up sequencing: any of VDD, VSS, or VCC may be applied first without causing crowbar currents or latch-up. However, both analog (VDD/VSS) and digital (VCC) supplies must be stable before issuing SPI commands or expecting valid wiper operation. The amplifier remains disabled until all three supplies meet their respective minimum thresholds, as verified in the Absolute Maximum Ratings and Applications Information sections.