Analog Devices Inc./Maxim Integrated MAX16999AUA33+T

Overview

MAX16999AUA33+T from Maxim Integrated is a low-quiescent-current linear regulator delivering 100mA at 3.3V output, operating from 2.5V–5.5V input, with 13μA typical quiescent current and −40°C to +125°C operation. It features active-low open-drain RESET with programmable timeout via external CRES capacitor, logic-controlled enable (EN), and thermal/short-circuit protection-designed for always-on μC core or interrupt supply in automotive telematics and industrial control.

For engineers reviewing the MAX16999AUA33+T datasheet, MAX16999AUA33+T pinout, MAX16999AUA33+T application, or MAX16999AUA33+T equivalent, key selection criteria include ultra-low IQ for battery-backed keep-alive timers, factory-trimmed 3.3V output accuracy (±2.5%), adjustable POR delay for power sequencing, and high-temperature reliability up to +125°C ambient.

Technical Context

The MAX16999AUA33+T integrates a p-channel MOSFET pass transistor, precision error amplifier, and internal 0.825×VREF reference to regulate 3.3V output with <0.1V dropout at 80mA. Its POR timer uses a 10μA CRES pullup current charging an external capacitor to generate reset timeout, with fault-timer fallback ensuring startup even if CRES fails short.

Thermal shutdown activates at +165°C junction temperature with 15°C hysteresis, while undervoltage lockout disables regulation below 2.2V input (with 45mV hysteresis). EN input is internally latched via 120kΩ resistor, maintaining state during signal loss-critical for fail-safe microcontroller wake-up sequencing.

Key Specifications

Pinout & Package

MAX16999AUA33+T is housed in an 8-pin μMAX® package with exposed thermal pad (U8E+2 outline), optimized for high-power-density PCB layouts and thermal dissipation on multilayer boards (θJA = 77.6°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-quiescent linear regulator applications.

Compared with TPS7A0533PDBVR and NCP114AMX33TCG, the MAX16999AUA33+T uniquely combines ultra-low 13μA IQ, integrated programmable POR delay, and high-temperature reliability in a thermally enhanced μMAX package-making it irreplaceable in automotive telematics and industrial keep-alive systems requiring self-contained sequencing.

Availability

MAX16999AUA33+T is available at Aetrix Electronics and suitable for automotive telematics modules, industrial PLC keep-alive timers, and handheld device core bias applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX16999AUA33+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-performance analog and mixed-signal ICs for automotive, industrial, and communications markets-with emphasis on reliability, integration, and extreme-environment operation.

The MAX16999 series targets high-temperature linear regulation in safety-critical subsystems, specifically engineered for always-on μC core supply, POR sequencing, and fail-safe reset generation in harsh environments.

FAQ

What is the output voltage tolerance of the MAX16999AUA33+T over temperature and load?

The MAX16999AUA33+T delivers a factory-trimmed 3.3V output with ±2.5% accuracy across the full −40°C to +125°C temperature range and for load currents from 1mA to 100mA. This specification is guaranteed by design and 100% tested at +25°C, with no external components required to maintain this tolerance.

How does the CRES pin determine the RESET timeout in the MAX16999AUA33+T?

The CRES pin in the MAX16999AUA33+T sources a precise 10μA current to charge an external capacitor; RESET transitions from low to high-impedance when the CRES voltage reaches 600mV. The timeout is calculated as t = CCRES × 60 × 10³ seconds, enabling programmable delays from ~30ms to several seconds depending on capacitor value.

Can the MAX16999AUA33+T be used in parallel with another regulator?

Yes-the MAX16999AUA33+T is explicitly designed for parallel operation with other equal-voltage supplies (e.g., MAX1745), providing low-quiescent bias to μC cores while a higher-current regulator handles active loads. Its high output impedance in shutdown and controlled turn-on prevent backfeeding or instability.

What thermal protection features does the MAX16999AUA33+T include?

The MAX16999AUA33+T incorporates thermal-overload protection that disables the pass transistor when junction temperature exceeds +165°C, with 15°C hysteresis. During sustained overload, it enters pulsed operation-allowing thermal monitoring while preventing permanent damage. Its μMAX-EP package achieves θJA = 77.6°C/W on multilayer PCBs.

Is the EN pin of the MAX16999AUA33+T latched, and why does that matter?

Yes-the EN pin of the MAX16999AUA33+T is internally latched via a 120kΩ resistor, preserving its last state even if the EN signal line becomes disconnected. This ensures deterministic behavior during transient faults or connector vibration, critical for automotive and industrial systems where signal integrity cannot be assumed.