Analog Devices Inc./Maxim Integrated MAX16999AUA05+T

Overview

MAX16999AUA05+T from Maxim Integrated is a low-quiescent-current linear regulator delivering 100mA at 0.5V output with 13μA typical ground current, operating from 2.5V–5.5V input across –40°C to +125°C. It integrates an active-low open-drain reset with adjustable POR timeout via CRES capacitor, logic-controlled enable, and thermal/short-circuit protection-designed for always-on μC core or interrupt supply in automotive telematics and industrial keep-alive systems.

For engineers reviewing the MAX16999AUA05+T datasheet, MAX16999AUA05+T pinout, MAX16999AUA05+T application, or MAX16999AUA05+T equivalent, key selection criteria include ultra-low 0.5V fixed output, 13μA quiescent current at light load, ±2.5% output accuracy over temperature, 8-pin μMAX-EP package with exposed pad for thermal management, and programmable reset timeout using external CRES capacitance.

Technical Context

The MAX16999AUA05+T uses a p-channel MOSFET pass transistor with internal feedback divider to regulate 0.5V output, supported by a precision 0.825×VREF error amplifier reference. Its POR timer relies on 10μA CRES pullup current charging an external capacitor to 600mV threshold, enabling deterministic reset timeout independent of supply ramp rate.

Thermal shutdown activates at +165°C (15°C hysteresis), while undervoltage lockout disables regulation below 2.2V VIN with 45mV hysteresis. The EN input features 120kΩ internal pullup/pulldown latching, ensuring stable state retention even if the control line disconnects.

Key Specifications

Pinout & Package

MAX16999AUA05+T is housed in an 8-pin μMAX-EP package (outline 21-0107) with exposed paddle (EP) soldered to PCB ground plane for thermal conduction and EMI reduction.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16999AUA05+T, TPS7A0505PDBVR offers smaller footprint but omits the integrated CRES-based POR timer and latch-enabled EN, while NCP114AMX050TBG lacks both reset and UVLO-making MAX16999AUA05+T uniquely suited for automotive and industrial systems requiring guaranteed power-up sequencing and fault-resilient operation.

Availability

MAX16999AUA05+T is available at Aetrix Electronics and suitable for automotive telematics, industrial sensor nodes, and keep-alive timer applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX16999AUA05+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 precision analog, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX16999 series targets high-reliability, high-temperature linear regulation-specifically engineered for always-on subsystems in automotive and industrial electronics where ultra-low quiescent current and deterministic power-up behavior are critical.

FAQ

What is the exact output voltage tolerance of MAX16999AUA05+T over temperature?

The MAX16999AUA05+T guarantees ±2.5% output voltage accuracy over the full –40°C to +125°C operating temperature range, verified for 0.5V output with 1mA–80mA load current. This specification holds regardless of input voltage variation within 2.5V–5.5V, ensuring stable bias for sensitive low-voltage logic and memory interfaces throughout thermal cycling.

How does the CRES capacitor value affect the reset timeout of MAX16999AUA05+T?

The CRES capacitor directly sets the MAX16999AUA05+T reset timeout via the formula t_{POR_DELAY} = C_CRES × 60 × 10³ seconds, where C_CRES is in farads. For example, a 15nF capacitor yields ~90ms timeout, while the datasheet specifies 30–80ms range with CRES = GND. The internal 10μA pullup current charges CRES to 600mV threshold, making timeout highly predictable and immune to supply ramp variations.

Can MAX16999AUA05+T be used in parallel with another regulator of the same output voltage?

Yes, MAX16999AUA05+T is explicitly designed for parallel operation with equal-voltage supplies-such as pairing with a high-current regulator to reduce overall system quiescent power. Its output impedance and enable timing allow seamless current sharing without external ballast components, provided both regulators share common IN and GND paths and use matched output capacitors.

What thermal derating applies to MAX16999AUA05+T on a multilayer PCB?

On a multilayer PCB, MAX16999AUA05+T has θ_JA = 77.6°C/W and maximum continuous power dissipation of 1030.9mW at +70°C ambient. Derating is 12.9mW/°C above +70°C, meaning usable power drops to ~773mW at +90°C ambient. The exposed pad (EP) must be soldered to a solid ground plane to achieve this rating; insufficient thermal land area will degrade performance.

Does MAX16999AUA05+T include undervoltage lockout, and what is its threshold?

Yes, MAX16999AUA05+T includes built-in undervoltage lockout (UVLO) that disables regulation when input voltage falls below 2.2V (max) with 45mV hysteresis. Below this threshold, OUT goes high-impedance and EN is ignored-preventing erratic behavior during brownout conditions. UVLO re-enables regulation only after VIN rises above 2.245V, ensuring clean startup in automotive and industrial power systems.