Analog Devices Inc./Maxim Integrated MAX38902AETA+

Overview

MAX38902AETA+ from Analog Devices is a low-noise, pin-selectable 500mA LDO linear regulator delivering 10.5µVRMS output noise (10Hz–100kHz), ±1% DC output accuracy over load/line/temperature, and only 100mV max dropout at 500mA with 3.6V input. It features active discharge (800Ω), programmable soft-start via BYP capacitor, and operates from 1.7V to 5.5V input for powering sensitive analog circuitry in high-resolution data acquisition systems.

For engineers reviewing the MAX38902AETA+ datasheet, MAX38902AETA+ pinout, MAX38902AETA+ application, or MAX38902AETA+ equivalent, key selection criteria include its nine factory-configurable output voltages (1.2V–5.0V), TDFN-8 package compatibility, ultra-low noise performance, and integrated thermal/overcurrent protection - critical for noise-sensitive power domains in precision instrumentation and audio front-ends.

Technical Context

The MAX38902AETA+ uses a pMOS pass transistor architecture enabling ultra-low dropout and reverse-current protection triggered when VIN falls 10mV below VOUT. Its reference voltage is internally trimmed to 0.6V, and output voltage selection is determined by SELA/SELB logic states sampled at enable startup - not dynamically reconfigurable during operation.

Regulator stability relies on a 2µF minimum ceramic output capacitor and a 0.001–0.1µF BYP-to-OUT capacitor that simultaneously filters reference noise and sets soft-start slew rate (e.g., 5V/ms with 0.01µF). PSRR remains ≥70dB at 1kHz and 10kHz, supporting rejection of switching supply ripple in mixed-signal systems.

Key Specifications

Pinout & Package

MAX38902AETA+ is housed in an 8-pin, 2mm × 2mm TDFN package (package code T822+3C) with exposed pad (EP) for thermal dissipation. The pinout is optimized for low-noise layout: IN and GND bypass paths are isolated, BYP is decoupled directly to OUT, and SELA/SELB inputs are high-impedance (1MΩ) for flexible voltage selection without loading.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO regulator applications.

Compared with MAX8902AETA+, MAX38902AETA+ delivers 2.4× lower output noise and integrated active discharge for tighter power sequencing control; versus TPL7407LADGNR, it trades resistor-based adjustability for simplified layout, faster enable response, and guaranteed ±1% accuracy without calibration overhead.

Availability

MAX38902AETA+ is available at Aetrix Electronics and suitable for high-resolution data acquisition systems, audio signal processing modules, communication circuitry, and industrial sensor nodes requiring stable component supply, long-term manufacturability, and consistent parametric performance across temperature and load.

Supply support for MAX38902AETA+ 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

MAX38902AETA+ belongs to Analog Devices' precision low-noise LDO family, engineered specifically for powering noise-sensitive analog signal chains where PSRR, output accuracy, and fast transient response are critical design constraints.

FAQ

What output voltages does the MAX38902AETA+ support?

The MAX38902AETA+ supports nine fixed output voltages: 1.2V, 1.5V, 1.8V, 2.5V, 3.0V, 3.1V, 3.3V, 4.0V, and 5.0V. These are selected using the SELA and SELB pins, which are sampled only at power-up or EN assertion. For example, connecting SELA to GND and SELB to GND configures the MAX38902AETA+ for 3.0V output. No external resistors are required.

How does the active discharge feature work on the MAX38902AETA+?

When the EN pin of the MAX38902AETA+ is pulled low, an internal 800Ω resistor connects the OUT pin to GND, rapidly discharging output capacitance. This feature ensures predictable, sub-millisecond discharge times - critical for safe power sequencing in multi-rail systems. The discharge path remains active until EN is reasserted high, and it operates independently of load conditions or input voltage level.

Can the MAX38902AETA+ be used with ceramic output capacitors smaller than 4.7µF?

Yes - the MAX38902AETA+ is stable with a minimum 2µF ceramic output capacitor (including DC bias derating), unlike many legacy LDOs requiring ≥10µF. A 4.7µF X5R/X7R capacitor is recommended for margin, but designs using 2.2µF or 3.3µF ceramics meeting ESR <0.03Ω remain fully stable. This enables compact layouts and reduced bill-of-materials cost.

What is the purpose of the BYP pin on the MAX38902AETA+?

The BYP pin on the MAX38902AETA+ connects a capacitor (0.001µF–0.1µF) to the OUT pin to filter reference noise and set the soft-start slew rate. A 0.01µF BYP capacitor yields a 5V/ms startup ramp, limiting inrush current to ~50mA for a 10µF output cap. This controlled ramp prevents input rail droop and avoids false triggering of upstream power monitors during system boot.

Does the MAX38902AETA+ provide reverse-current protection?

Yes - the MAX38902AETA+ includes integrated reverse-current protection that activates when VIN falls 10mV below VOUT. At that point, the internal pMOS pass device is turned off, blocking reverse current flow from the output capacitor into the input supply. This protects upstream sources during brown-out or hot-swap events and eliminates the need for an external series diode or MOSFET.