Analog Devices Inc./Maxim Integrated MAX16999AUA11+

Overview

MAX16999AUA11+ from Maxim Integrated is a high-temperature ultra-low-quiescent-current linear regulator delivering 100mA at preset 1.1V output, operating from 2.5V to 5.5V input, with 13μA typical quiescent current and active-low open-drain reset with programmable POR delay via external CRES capacitor. It serves as a parallel low-I_Q supply for microcontroller core/interrupt sections during sleep mode in telematics and industrial control systems.

For engineers reviewing the MAX16999AUA11+ datasheet, MAX16999AUA11+ pinout, MAX16999AUA11+ application, or MAX16999AUA11+ equivalent, key selection criteria include guaranteed operation up to +125°C ambient, ±2.5% output voltage accuracy over load/temperature, thermal shutdown at +165°C, logic-controlled enable with latched state, and reset timeout programmability via CRES capacitance.

Technical Context

The MAX16999AUA11+ integrates a p-channel MOSFET pass transistor, precision bandgap reference, error amplifier, and dual-timer POR circuitry. Its reset function uses a 10μA pullup current on CRES to charge an external capacitor until reaching 600mV threshold, triggering high-impedance RESET release after timeout.

Thermal protection employs a +165°C shutdown threshold with 15°C hysteresis, enabling pulsed regulation under sustained overload. UVLO activates below 2.2V (max) with 45mV hysteresis, forcing OUT into high-impedance state independent of EN state.

Key Specifications

Pinout & Package

MAX16999AUA11+ is housed in an 8-pin μMAX® package with exposed thermal pad (U8E+2 outline), optimized for high-power-density PCB layouts in thermally constrained applications.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16999AUA11+, both alternatives lack integrated programmable POR reset and thermal robustness for +125°C ambient operation, making them unsuitable for automotive telematics or industrial motor control where deterministic power-up and high-temperature reliability are mandatory.

Availability

MAX16999AUA11+ is available at Aetrix Electronics and suitable for industrial motor control, telematics ECUs, and SDRAM power supplies requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for MAX16999AUA11+ 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 demanding industrial, automotive, and communications applications.

The MAX16999 series targets high-reliability power management in extreme-temperature environments, specifically engineered for always-on microcontroller subsystems requiring ultra-low quiescent current and integrated power-on reset.

FAQ

What is the exact output voltage of MAX16999AUA11+ and how is it set?

The MAX16999AUA11+ delivers a factory-preset 1.1V output, confirmed by the "11" suffix in its part number per Maxim's Selector Guide. This voltage is internally trimmed using laser calibration during wafer sort and requires no external resistors or configuration. The 1.1V output matches common microcontroller core voltage rails, enabling direct integration without feedback network design. MAX16999AUA11+ maintains ±2.5% accuracy across -40°C to +125°C ambient and 1mA–100mA load range.

How does the CRES pin control reset timeout in MAX16999AUA11+?

The CRES pin on MAX16999AUA11+ accepts an external capacitor that sets the power-on reset timeout duration. An internal 10μA current source charges the capacitor until it reaches ~600mV, at which point the RESET pin transitions from low to high-impedance. Using the formula t = C_CRES × 60 × 10³, a 15nF capacitor yields ~90ms timeout. MAX16999AUA11+ also includes a 100ms fault timer to prevent indefinite reset assertion if CRES is shorted or missing.

Does MAX16999AUA11+ support parallel operation with other regulators?

Yes, MAX16999AUA11+ is explicitly designed for parallel operation with equal-voltage supplies. When disabled via EN = low, its OUT pins go high-impedance, eliminating reverse current flow and enabling seamless stacking with higher-current regulators like the MAX1745. This architecture allows MAX16999AUA11+ to serve as a low-quiescent "keeper" supply while the main regulator handles dynamic loads - a configuration validated in Maxim's Figure 2 reference design.

What thermal performance can be expected from MAX16999AUA11+ at +125°C ambient?

MAX16999AUA11+ delivers full 100mA output current at +125°C ambient when mounted on a multilayer PCB, thanks to its 77.6°C/W θ_JA and +165°C thermal shutdown threshold. Its exposed paddle (EP) must be soldered to a minimum 100mm² copper area for optimal heat transfer. At +125°C, junction temperature remains below +150°C limit with 100mA load and 3.3V input, satisfying industrial and automotive under-hood requirements without derating.

Is MAX16999AUA11+ RoHS-compliant and what package does it use?

Yes, MAX16999AUA11+ is RoHS-compliant, indicated by the "+" suffix per Maxim's ordering nomenclature. It uses the 8-pin μMAX® package with exposed thermal pad (outline U8E+2), measuring 3mm × 3mm × 0.8mm. The exposed paddle must be soldered to PCB ground for both thermal management and EMI reduction. This compact, thermally enhanced package enables high-density placement in space-constrained telematics and industrial modules.