Analog Devices Inc./Maxim Integrated MAX6771TASD2+T

Overview

MAX6771TASD2+T from Maxim Integrated is a dual-enable, automotive-grade micropower linear regulator with integrated supervisor and watchdog timer. It operates from 4V to 72V input, delivers 100mA output at fixed 3.3V, features open-drain active-low RESET with 12.5ms timeout (D2 suffix), and supports ignition-switch + bus-transceiver enable schemes. Used in automotive body control modules for stable low-power microcontroller supply under cold-crank conditions.

For engineers reviewing the MAX6771TASD2+T datasheet, MAX6771TASD2+T pinout, MAX6771TASD2+T application, or MAX6771TASD2+T equivalent, key selection criteria include dual-enable logic compatibility, AEC-Q100 qualification, 31µA quiescent current, 620mV dropout at 100mA/3.3V, and 12.5ms reset timeout - all critical for always-on vehicle subsystems requiring robust brownout recovery.

Technical Context

The MAX6771TASD2+T implements dual active-high enable inputs (ENABLE1 and ENABLE2) to support independent control via ignition switch and CAN/LIN transceiver signals, enabling flexible power sequencing in automotive gateways. Its supervisor circuit monitors the regulated 3.3V output and asserts an open-drain RESET signal when voltage falls below 2.888V (S threshold), holding it low for ≥12.5ms after recovery.

This variant includes a 50ms watchdog timer (MAX6771B-series designation confirmed by D2 suffix and S output code per Table 2), which triggers RESET if WDI remains static beyond timeout - a feature essential for fail-safe microcontroller supervision in ASIL-B systems. Thermal shutdown activates at +160°C with 20°C hysteresis, and overcurrent protection limits sink current to 150–250mA during short-circuit events.

Key Specifications

Pinout & Package

MAX6771TASD2+T uses a thermally enhanced 6-pin TDFN-EP package (3mm × 3mm, exposed pad), rated for 1.951W dissipation on multilayer PCBs. The exposed pad (EP) must be soldered to ground plane for thermal and EMI performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar automotive linear regulator with supervisor applications.

Compared with MAX6772TASD2+T, the MAX6771TASD2+T offers identical electrical and thermal performance with certified tape-and-reel delivery for automated SMT lines; versus TLV70733PDQNR, it provides 72V input tolerance, dual-enable sequencing, and integrated 50ms watchdog - essential for ASIL-compliant automotive power domains.

Availability

MAX6771TASD2+T is available at Aetrix Electronics and suitable for automotive body control modules, door ECU designs, and seat control units requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX6771TASD2+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) designs high-reliability analog and mixed-signal ICs for automotive, industrial, and communications markets, with deep expertise in power management and supervisory circuits.

The MAX6765–MAX6774B family was engineered specifically for automotive always-on modules, combining ultra-low quiescent current, wide-input voltage tolerance, and integrated supervision to meet AEC-Q100 and ISO 16750 requirements.

FAQ

What is the function of the TIMEOUT pin on the MAX6771TASD2+T?

The TIMEOUT pin on the MAX6771TASD2+T sets the duration of the active-low RESET assertion after brownout recovery. When connected to the OUT pin, it configures a fixed 12.5ms timeout (D2 suffix). For adjustable timing, a capacitor is connected from TIMEOUT to GND. This pin directly controls the reset pulse width critical for MCU initialization stability in automotive applications.

Does the MAX6771TASD2+T support adjustable output voltage?

No, the MAX6771TASD2+T provides a fixed 3.3V output (S suffix per Table 2). Adjustable output (1.8V–11V) is only supported by MAX6767–MAX6774B variants with SET pin functionality. The MAX6771TASD2+T lacks the SET pin and internal feedback divider for voltage adjustment - its output is factory-trimmed and unchangeable.

Is the MAX6771TASD2+T qualified for automotive use?

Yes, the MAX6771TASD2+T is AEC-Q100 qualified and specified for -40°C to +125°C operation. Its 3mm × 3mm TDFN-EP package, 1.951W thermal dissipation capability, and built-in protections (overtemperature, short-circuit, brownout) meet stringent automotive reliability standards for under-hood and chassis-mounted ECUs.

How does the dual-enable feature work on the MAX6771TASD2+T?

The MAX6771TASD2+T uses ENABLE1 and ENABLE2 as independent active-high inputs: ENABLE1 typically connects to ignition switch voltage, while ENABLE2 links to bus transceiver READY signal. Both must be high to activate regulation. Either input pulled low disables the regulator, enabling coordinated power control between vehicle key state and communication bus activity - a core requirement for automotive gateway architectures.

What watchdog timeout period does the MAX6771TASD2+T implement?

The MAX6771TASD2+T implements a 50ms watchdog timeout, confirming it belongs to the MAX6771B subfamily (per datasheet distinction between MAX6773/MAX6774 = 1.6s and MAX6773B/MAX6774B = 50ms). This fast timeout is optimized for real-time fault detection in safety-critical body domain functions like window lift or mirror control, where rapid MCU reset is mandatory.