Analog Devices Inc./Maxim Integrated MAX77839BEWL+T

Overview

The MAX77839BEWL+T from Analog Devices is a high-efficiency buck-boost DC-DC converter optimized for single-cell Li-ion and low-voltage battery chemistries (≥1.8V discharge), delivering 3A continuous output current with 6μA quiescent current, 2.2MHz switching frequency, and 2.3V–5.3V single-resistor adjustable output voltage. It operates in WLP package (2.07mm × 1.51mm, 15-bump) and supports POK (power-ok) open-drain output functionality for system power sequencing in compact portable electronics.

For engineers reviewing the MAX77839BEWL+T datasheet, MAX77839BEWL+T pinout, MAX77839BEWL+T application, or MAX77839BEWL+T equivalent, this page delivers verified technical context, validated pin functions, confirmed WLP package mapping, real-world application constraints, and two rigorously cross-checked alternative parts - all grounded in the official MAX77839 datasheet Rev 2 (Jan 2022).

Technical Context

The MAX77839BEWL+T implements a four-switch H-bridge buck-boost topology with fixed 2.2MHz PWM control and current-mode compensation, enabling seamless mode transition between buck (VIN > VOUT) and boost (VIN < VOUT) without discontinuity. Its proprietary phase control (Φ1–Φ4) manages inductor energy transfer using input-side (LX1) and output-side (LX2) switching nodes.

It integrates cycle-by-cycle peak current limiting (3.6A typical for "C/D" variants), active output discharge (100Ω internal switch), undervoltage lockout (1.75V rising threshold), overvoltage protection (0.5V differential OVP), and thermal shutdown (150°C). The GPIO pin is configured as POK output per ordering option "B", pulling low when VOUT is within ±10% of target.

Key Specifications

Pinout & Package

The MAX77839BEWL+T is supplied in a 2.07mm × 1.51mm, 0.4mm pitch, 15-bump wafer-level package (WLP), compatible with standard SMT assembly and reflow profiles. Thermal resistance θJA = 61.65°C/W (4-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck-boost regulator applications.

Compared with MAX77839AEWL+T, the MAX77839BEWL+T trades higher current capability for integrated POK functionality - essential for autonomous power sequencing in battery-powered SoC systems. Against TPS63802DLAR, it offers superior GPIO configurability and lower IQ, at the cost of slightly larger WLP footprint and vendor-specific ecosystem integration.

Availability

MAX77839BEWL+T is available at Aetrix Electronics and suitable for asset tracking, smartphone sensor subsystems, and 5G/GSM cellular modules requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MAX77839BEWL+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

Analog Devices (acquired Maxim Integrated in 2021) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and consumer markets.

The MAX77839 product line targets ultra-low-power, space-constrained portable electronics - designed specifically for single-cell battery systems needing seamless buck-boost regulation, minimal quiescent current, and flexible system integration via GPIO configuration.

FAQ

What is the GPIO function of the MAX77839BEWL+T?

The GPIO pin on the MAX77839BEWL+T is configured as a POK (power-ok) open-drain output per its "B" ordering option. It pulls low when the regulated output voltage is within ±10% of the target value set by the RSEL resistor. An external pull-up resistor (e.g., 15kΩ to VIO) is required to generate a logic-high signal during valid regulation. This behavior is fixed for MAX77839BEWL+T and cannot be reconfigured as FPWM input.

What package does the MAX77839BEWL+T use, and what are its key mechanical dimensions?

The MAX77839BEWL+T uses a 15-bump wafer-level package (WLP) with outline number 21-100441. Its body dimensions are 2.07mm × 1.51mm, with 0.4mm bump pitch and 0.27mm nominal bump height. The package is RoHS-compliant (lead-free), marked with "+T" indicating tape-and-reel delivery. Land pattern follows Application Note 1891, and thermal resistance θJA is 61.65°C/W on a four-layer board.

How is the output voltage set on the MAX77839BEWL+T?

The output voltage of the MAX77839BEWL+T is set by connecting a precision resistor (RSEL) between the SEL pin and AGND. The device reads this resistance during startup (tRSEL ≈ 450μs) to determine the target VOUT. For example, a 0Ω connection yields 3.3V; a 4.99kΩ resistor yields 2.3V. Table 1 in the datasheet lists 33 validated RSEL values covering 2.3V–5.3V in 0.1V increments. Resistor tolerance must be ≤1% to maintain output accuracy within ±3.5%.

Does the MAX77839BEWL+T support active output discharge, and how does it operate?

Yes, the MAX77839BEWL+T includes integrated active output discharge. When the device is disabled via EN pin low or latched off by protection (e.g., thermal shutdown or UVLO), an internal 100Ω switch connects OUT to PGND, rapidly discharging the output capacitor. This prevents residual voltage from holding downstream logic in undefined states or causing back-powering. The discharge path is automatically disconnected when the regulator is enabled and regulating normally.

What are the key protections built into the MAX77839BEWL+T?

The MAX77839BEWL+T integrates five core protections: (1) Undervoltage lockout (UVLO) with 1.75V rising threshold and 70mV hysteresis; (2) Overvoltage protection (OVP) triggered by 0.5V differential between OUT and OUTS; (3) Cycle-by-cycle inductor peak current limiting (3.6A typical); (4) Thermal shutdown at +150°C with 15°C hysteresis; and (5) Soft-start timeout (4ms) that latches off the device if VOUT fails to reach 90% of target. All protections cause immediate shutdown and require EN or VIN cycling to recover.