Analog Devices Inc./Maxim Integrated MAX1615AEUK

Overview

The MAX1615AEUK from Maxim Integrated is a micropower, fixed-output linear regulator in SOT23-5 package, delivering 3.3V or 5V at up to 30mA output current with 8µA max quiescent supply current and 4V–28V input range. It provides keep-alive power for CMOS RAM and microcontrollers in high-voltage battery systems such as notebook computers and smart-battery packs.

For engineers reviewing the MAX1615AEUK datasheet, MAX1615AEUK pinout, MAX1615AEUK application, or MAX1615AEUK equivalent, key selection criteria include dropout voltage (350mV @30mA), ±2% initial output accuracy, thermal shutdown at +150°C, and pin-selectable output configuration - critical for low-power backup and always-on subsystems.

Technical Context

The MAX1615AEUK uses a PNP pass transistor architecture enabling low dropout and ultra-low quiescent current. Its internal resistor divider and 5/3 pin select logic determine fixed 3.3V (5/3 = GND) or 5V (5/3 = OUT) output without external feedback components.

Shutdown is active-low on SHDN pin, reducing supply current to <1µA; thermal overload protection engages at +150°C with +20°C hysteresis. The device requires only a 5µA minimum load to maintain regulation and supports fast line transients during battery-to-adapter switchover.

Key Specifications

Pinout & Package

SOT23-5 package: 2.9mm × 1.6mm footprint, 1.1mm height, thermally enhanced GND pad for 571mW dissipation at +70°C ambient.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS76333DBVR and MCP1700T-3302E/MB, the MAX1615AEUK uniquely balances ultra-low I_Q, pin-selectable output, integrated shutdown, and thermal protection in a single SOT23-5 package - making it optimal for space-constrained, long-life backup power designs where both 3.3V and 5V variants share the same layout.

Availability

MAX1615AEUK is available at Aetrix Electronics and suitable for notebook computers, smart-battery packs, and microcontroller keep-alive circuits requiring stable component supply across extended production lifecycles.

Supply support for MAX1615AEUK 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, computing, and portable applications.

The MAX1615AEUK belongs to Maxim's high-voltage, micropower linear regulator product line, engineered specifically for battery-backed systems requiring ultra-low quiescent current and robust operation across wide input voltage ranges.

FAQ

What output voltage does the MAX1615AEUK deliver, and how is it selected?

The MAX1615AEUK delivers either 3.3V or 5.0V, selected by the state of its 5/3 pin: connect pin 4 (5/3) to GND for 3.3V output, or to OUT for 5.0V output. This pin-selectable feature eliminates external feedback resistors and allows one PCB layout to support both output voltages. The MAX1615AEUK achieves ±2% initial accuracy across temperature and load, ensuring reliable logic-level compatibility in both configurations.

How does the MAX1615AEUK achieve ultra-low quiescent current, and what is its impact on battery life?

The MAX1615AEUK achieves 8µA maximum quiescent supply current through optimized biasing and PNP pass transistor architecture. In a typical 3.3V SRAM backup application drawing 5µA minimum load, this enables over two years of operation from a standard CR2032 coin cell. The MAX1615AEUK maintains this low I_Q across its full 4V–28V input range and -40°C to +85°C operating temperature, making it ideal for long-duration keep-alive functions.

What protection features does the MAX1615AEUK include, and how do they operate?

The MAX1615AEUK integrates foldback current limiting and thermal shutdown. Current limit activates at ~100mA (typical), protecting against short-circuit conditions for up to 30 seconds. Thermal shutdown triggers at +150°C junction temperature, disabling the pass transistor until the die cools by +20°C hysteresis. These protections require no external components and ensure robust operation in compact, thermally constrained layouts where the MAX1615AEUK is deployed.

Can the MAX1615AEUK be used in shutdown mode, and what is its shutdown current?

Yes - the MAX1615AEUK enters ultra-low-power shutdown when its SHDN pin is pulled low, reducing supply current to <1µA (typical). This mode disables the pass transistor, reference, and all internal bias circuits. The MAX1615AEUK resumes regulation within 1ms of SHDN returning high. For automatic startup, tie SHDN to IN; for controlled sequencing, drive SHDN from a system controller - a key capability for power-managed embedded systems.

What are the minimum and recommended capacitor requirements for stable operation of the MAX1615AEUK?

The MAX1615AEUK requires a minimum 0.1µF ceramic capacitor on IN and 1µF on OUT. For full 30mA load capability, a 4.7µF output capacitor is recommended; values below 1µF may cause instability or excessive transient deviation. The output capacitor's ESR must remain below 1Ω. These values ensure stable regulation, optimal line-transient response, and compliance with the MAX1615AEUK's internal compensation - verified in Maxim's typical application circuits.