Analog Devices Inc./Maxim Integrated MAX38904AATD+

Overview

MAX38904AATD+ from Analog Devices is a 2A, low-noise LDO linear regulator in a 3mm × 3mm 14-pin TDFN package, delivering ±1% output accuracy over load, line, and temperature with only 47mV dropout at full load and 5.1μVRMS output noise (10Hz–100kHz). It features pin-selectable fixed outputs (1.2V–5.0V), active discharge (70Ω), and operates across 1.7V–5.5V input range - ideal for powering high-resolution ADCs and precision analog front-ends in medical instrumentation.

For engineers reviewing the MAX38904AATD+ datasheet, MAX38904AATD+ pinout, MAX38904AATD+ application, or MAX38904AATD+ equivalent, this page provides verified technical context, validated pin functions, confirmed application use cases, and two rigorously cross-checked alternative parts for system-level power design decisions.

Technical Context

The MAX38904AATD+ implements a PMOS-based LDO architecture with internal 0.6V reference and dual configuration pins (SELA/SELB) that are sampled at enable to select one of nine factory-trimmed output voltages. Its low-noise performance stems from a dedicated BYP pin filtering the internal reference and feedback path, while its 70Ω active discharge circuit ensures rapid output capacitor discharge during shutdown.

Thermal protection triggers at 165°C junction temperature with hysteresis (150°C turn-on), and reverse-current protection activates when VIN falls 10mV below VOUT, blocking body-diode conduction. The device maintains stability with ≥8μF ceramic output capacitance and requires no external compensation due to internal unity-gain compensation.

Key Specifications

Pinout & Package

MAX38904AATD+ uses a 3mm × 3mm, 14-pin TDFN package with exposed thermal pad (EP). Pin assignments are validated per Maxim Integrated (now Analog Devices) datasheet Rev 9, March 2023.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A8300RGRT and LT3045EDD#PBF, the MAX38904AATD+ uniquely combines pin-selectable outputs, 70Ω active discharge, and 3mm × 3mm TDFN packaging - enabling compact, sequenced, and noise-sensitive analog power delivery without external configuration components.

Availability

MAX38904AATD+ is available at Aetrix Electronics and suitable for medical imaging signal chains, high-resolution data acquisition systems, and high-end audio DAC supplies requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX38904AATD+ 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, communications, automotive, and healthcare markets.

The MAX38904 family was designed specifically for noise-critical analog power delivery in portable and high-density systems - emphasizing ultra-low noise, minimal dropout, and small-footprint packaging without sacrificing protection or accuracy.

FAQ

What output voltages does the MAX38904AATD+ support?

The MAX38904AATD+ 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 at power-up by the logic states (Hi-Z, IN, or GND) applied to the SELA and SELB pins, as defined in Table 1 of the MAX38904AATD+ datasheet. No external resistors are needed - all configurations are factory-trimmed and verified.

Does the MAX38904AATD+ include reverse-current protection?

Yes, the MAX38904AATD+ includes integrated reverse-current protection. When the input voltage (VIN) falls 10mV below the output voltage (VOUT), the device automatically shuts off the PMOS pass transistor, blocking reverse current flow through the body diode. This prevents battery drain or bus contention in systems with multiple power domains or hot-swap capability - a key feature confirmed in the MAX38904AATD+ Electrical Characteristics table.

What is the minimum output capacitance required for stability with the MAX38904AATD+?

The MAX38904AATD+ requires a minimum of 8μF ceramic output capacitance (X5R or X7R dielectric) for guaranteed stability across temperature and DC bias. This value includes derating - actual installed capacitance must remain ≥8μF under operating voltage and temperature. The MAX38904AATD+ datasheet specifies this in both the Electrical Characteristics and Output Capacitor sections, and stability is maintained without external compensation components.

How does the active discharge function work on the MAX38904AATD+?

When the EN pin is pulled low, the MAX38904AATD+ connects a 70Ω resistor between the OUT pin and GND, actively discharging output capacitors. This feature reduces discharge time significantly - for example, a 22μF capacitor discharges from 3.3V to 0.5V in under 1ms. The 70Ω value is specified in the MAX38904AATD+ Electrical Characteristics table and is independent of load or temperature.

Is the MAX38904AATD+ compatible with standard 3mm × 3mm TDFN footprints?

Yes, the MAX38904AATD+ uses the industry-standard 14-pin, 3mm × 3mm TDFN package with 0.5mm pitch and exposed thermal pad (package code T1433+2C). Its land pattern matches JEDEC MO-229WEED, and the recommended footprint (land pattern number 90-0063) is published in the MAX38904AATD+ Package Information section. Thermal vias to ground are required for thermal performance.