Analog Devices Inc./Maxim Integrated MAX18002AWT+

Overview

MAX18002AWT+ from Analog Devices is an ultrasonic boost converter IC designed for low-noise, battery-powered systems. It operates from 0.5V to 5.5V input, delivers 2.5V–5.5V adjustable output in 100mV steps, features 3.6A cycle-by-cycle current limiting, True Shutdown™ with 7nA quiescent current, and automatic pass-through mode when VIN > VOUT - enabling efficient power management in wearables and IoT sensors.

For engineers reviewing the MAX18002AWT+ datasheet, MAX18002AWT+ pinout, MAX18002AWT+ application, or MAX18002AWT+ equivalent, key selection criteria include ultrasonic switching (29kHz typ) for audible-noise avoidance, RSEL-based voltage programming without feedback resistors, short-circuit protection limiting output current to 700mA below 0.5V, thermal shutdown at +165°C, and WLP package compatibility with space-constrained PCB layouts.

Technical Context

The MAX18002AWT+ implements adaptive on-time current-mode control to achieve fast transient response and high efficiency across load ranges. It dynamically transitions between ultrasonic mode (≥22kHz), skip mode, and continuous conduction mode based on load current - maintaining acoustic silence at light loads while optimizing regulation accuracy and efficiency at higher loads.

Its architecture integrates a high-side PMOS with 60–90mΩ R_DS(ON) and low-side NMOS with 30–60mΩ R_DS(ON), enabling pass-through operation when VIN exceeds VOUT. The internal RSEL ADC reads a single external resistor to set output voltage, eliminating traditional feedback dividers and reducing BOM count and power loss.

Key Specifications

Pinout & Package

MAX18002AWT+ uses a 1.07mm × 1.57mm, 0.5mm pitch, 6-bump wafer-level package (WLP) with bottom-side solder bumps. Thermal performance is characterized with θ_JA = 81.03°C/W on a four-layer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar boost converter applications.

Compared with TPS61291DRVR and LT3990EMSE#TRPBF, the MAX18002AWT+ uniquely combines ultrasonic switching, true input-output isolation in shutdown, and single-resistor VOUT programming - making it optimal for miniaturized, battery-constrained, and acoustically sensitive applications where design flexibility and long-term energy efficiency are critical.

Availability

MAX18002AWT+ is available at Aetrix Electronics and suitable for wearable health sensors, IoT edge nodes, and portable medical diagnostics requiring stable component supply, RoHS-compliant packaging, and guaranteed long-term availability for production ramp.

Supply support for MAX18002AWT+ 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

Analog Devices, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX18002AWT+ belongs to Analog Devices' ultralow-power boost converter product line, engineered specifically for space- and energy-constrained battery-powered applications demanding silent operation, minimal quiescent current, and flexible output configuration.

FAQ

What is the minimum input voltage required to start up the MAX18002AWT+?

The MAX18002AWT+ has a typical start-up voltage of 1.8V. It can operate continuously down to 0.5V after startup, but initial biasing and internal circuit activation require VIN ≥ 1.8V (with ±0.05V tolerance per datasheet). Below this threshold, the EN pin remains inactive and no switching occurs. This ensures reliable cold-start capability from partially discharged batteries while maintaining regulation stability.

How does the MAX18002AWT+ implement True Shutdown™, and what happens to the OUT pin during shutdown?

The MAX18002AWT+ implements True Shutdown™ by fully disconnecting both the high-side and low-side power switches when EN is pulled low, resulting in bidirectional isolation between VIN and VOUT. During shutdown, the OUT pin is actively discharged through a 100Ω internal resistor to GND, preventing floating output conditions. This behavior ensures zero reverse current flow and eliminates leakage paths that could drain backup batteries in always-off systems.

Can the MAX18002AWT+ be used in applications requiring output voltages above 5.0V?

Yes, the MAX18002AWT+ supports output voltages up to 5.5V, but ultrasonic mode (USM) is explicitly disabled for VOUT > 5.0V per datasheet specification. At 5.1V–5.5V, the device operates in skip or CCM mode with standard switching frequencies - which may introduce audible noise under light loads. For noise-sensitive applications above 5.0V, external filtering or mechanical damping should be considered.

What is the purpose of the RSEL pin, and how accurate must the external resistor be?

The RSEL pin on the MAX18002AWT+ connects to a single external resistor to GND, enabling precise output voltage selection from 2.5V to 5.5V in 100mV increments. The internal ADC requires ±1% resistor tolerance to ensure ±1% output accuracy - verified across temperature and process variation. Using tighter-tolerance resistors does not improve regulation; standard 1% metal-film or thick-film resistors are sufficient and recommended.

Does the MAX18002AWT+ provide overtemperature protection, and how does it behave during thermal fault?

Yes, the MAX18002AWT+ includes thermal shutdown protection with a rising-threshold of +165°C (typ) and falling-threshold of +150°C (typ). When junction temperature exceeds +165°C, the IC disables switching and holds in shutdown until temperature falls below +150°C, then automatically resumes operation. This hysteresis prevents thermal oscillation and provides robust protection during sustained overload or poor heatsinking conditions.