Analog Devices Inc./Maxim Integrated MAX6329SHUT+

Overview

MAX6329SHUT+ from Maxim Integrated is a 150mA, +3.3V fixed-output, low-dropout linear regulator with integrated microprocessor reset circuit and active-low open-drain RESET output. It features 25µA quiescent current, 180mV dropout at 100mA, ±3.0% output accuracy, and operates from 2.5V to 5.5V input. Used in battery-powered handheld instruments and USB devices for stable power and reliable processor initialization.

For engineers reviewing the MAX6329SHUT+ datasheet, MAX6329SHUT+ pinout, MAX6329SHUT+ application, or MAX6329SHUT+ equivalent, key selection criteria include its preset +3.3V output, -5% reset threshold (SH suffix), SOT23-6 package, shutdown control (U suffix), and compatibility with 1µF ceramic output capacitors.

Technical Context

The MAX6329SHUT+ integrates a P-channel MOSFET LDO regulator core and a precision reset supervisor sharing the same 1.23V reference. Its regulator uses internal feedback for fixed +3.3V output (SET = GND), while the reset circuit monitors VOUT against a -5% threshold and asserts open-drain RESET for ≥100ms after recovery.

It includes thermal shutdown (160°C trip, 20°C hysteresis), short-circuit protection (350mA limit), reverse leakage protection, and SHDN-controlled shutdown (<1µA). The device requires no external components for basic operation beyond a 1µF output capacitor and supports manual reset only in MAX6349 variants - not applicable here.

Key Specifications

Pinout & Package

MAX6329SHUT+ is housed in a 6-pin SOT23-6 package with exposed pad for thermal dissipation. GND pin serves as both electrical reference and heatsink; recommended soldering to large PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LDO-with-reset applications.

Compared with MAX6329SHUT+, MAX6326TUT+T offers higher RESET drive but no shutdown capability, while TPS3808G33DBVR reduces size and quiescent current but sacrifices regulator integration and reverse leakage protection - making MAX6329SHUT+ optimal for space-constrained, battery-sensitive designs needing full power management.

Availability

MAX6329SHUT+ is available at Aetrix Electronics and suitable for hand-held instruments, USB devices, and palm top computers requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX6329SHUT+ 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 precision analog and mixed-signal ICs for power, sensing, and connectivity applications.

The MAX6329 series targets battery-powered portable electronics, integrating regulation and reset supervision to reduce component count and improve system reliability in space- and power-constrained environments.

FAQ

What output voltage does the MAX6329SHUT+ provide?

The MAX6329SHUT+ provides a fixed +3.3V regulated output with ±3.0% accuracy across 0°C to +85°C. This value is factory-trimmed and requires no external resistors - SET pin is tied to GND internally or externally to enable the preset mode. The output delivers up to 150mA and maintains regulation down to a 180mV input-output differential.

What does the 'SH' suffix in MAX6329SHUT+ indicate?

The 'SH' suffix in MAX6329SHUT+ specifies a -5% reset threshold (VTH = 0.95 × VOUT) and an active-low open-drain RESET output. The 'U' denotes the SHDN shutdown input, and 'T' indicates the SOT23-6 package. Together, SHUT+ confirms the device is the +3.3V, -5%, open-drain RESET, shutdown-enabled variant in tape-and-reel packaging.

Does the MAX6329SHUT+ require an external capacitor?

Yes, the MAX6329SHUT+ requires a minimum 1µF ceramic output capacitor between OUT and GND for stability across temperature and load. A 1µF capacitor on the IN-to-GND node is also recommended to improve line transient response and PSRR. X7R or X5R dielectrics are preferred; Z5U/Y5V types may require ≥2.2µF below -10°C.

How does the SHDN pin function on the MAX6329SHUT+?

The SHDN pin on the MAX6329SHUT+ is an active-low digital control input. When pulled low, it disables the regulator core, reducing total supply current to <1µA. During shutdown, OUT is unregulated and floats, RESET remains asserted (low), and all internal bias circuits power down. Connect SHDN to IN for normal operation; use a pullup resistor if driven by open-drain logic.

Is the MAX6329SHUT+ compatible with backup battery operation?

Yes, the MAX6329SHUT+ includes reverse leakage protection that blocks current flow from OUT to IN when VOUT > VIN - enabling safe backup battery operation (e.g., coin cell on OUT) without external diodes. This feature ensures no parasitic discharge of the backup source while the main supply is active or absent.