Analog Devices Inc./Maxim Integrated MAX77827BEFD+T

Overview

MAX77827BEFD+T from Maxim Integrated is a high-efficiency, ultra-low-quiescent-current buck-boost DC/DC converter designed for single-cell Li-ion battery systems. It delivers 2.3V–5.3V adjustable output with 1.8A switching current limit, 6μA typical IQ, 96% peak efficiency at 3.3V in/out, and seamless buck-boost mode transition - enabling stable rail generation in space-constrained wearables and LPWAN endpoints.

For engineers reviewing the MAX77827BEFD+T datasheet, MAX77827BEFD+T pinout, MAX77827BEFD+T application, or MAX77827BEFD+T equivalent, key selection factors include its 1.8A ILIM option (B/D variants), FC2QFN-14 package compatibility, 2.5MHz fixed-frequency PWM control, active output discharge, and POK/FPWM GPIO support for system-level power sequencing and monitoring.

Technical Context

The MAX77827BEFD+T implements a four-switch H-bridge buck-boost topology with current-mode PWM control at 2.5MHz nominal frequency, enabling compact 1μH inductor and minimal output capacitance (≥8μF). Its dual-mode operation - automatic SKIP at light load and forced FPWM for low ripple - is managed by internal logic that senses SEL resistor value and monitors VOUT against 92.5%/90% POK thresholds.

It integrates dedicated protection circuits including cycle-by-cycle overcurrent detection (1.8A ILIM), thermal shutdown at +165°C, UVLO with asymmetric rising/falling thresholds (1.75V/1.68V), soft-start (1.5ms typ), and 100Ω active output discharge. All functions operate within -40°C to +125°C junction temperature range using only two external resistors and standard passive components.

Key Specifications

Pinout & Package

MAX77827BEFD+T is packaged in a 2.5mm × 2.5mm, 14-lead FC2QFN (package code F142A2F+1) with 0.55mm pitch and exposed thermal pad. This RoHS-compliant package supports high-density PCB layouts and offers θ_JA = 63.4°C/W on a four-layer board.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS63802DLAR and NCP1529MUTBG, the MAX77827BEFD+T provides unique integration of POK monitoring, FPWM forcing, and resistor-programmable output - reducing external component count and enabling robust power sequencing in battery-critical designs.

Availability

MAX77827BEFD+T is available at Aetrix Electronics and suitable for smart wearables, LPWAN modems, and portable medical devices requiring stable component supply with guaranteed long-term availability and full traceability.

Supply support for MAX77827BEFD+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 consumer applications.

The MAX77827 product line targets ultra-low-power, high-efficiency DC/DC conversion in space-constrained battery-powered systems - emphasizing quiescent current optimization, seamless mode transition, and minimal external component count.

FAQ

What is the switching current limit specification for MAX77827BEFD+T?

The MAX77827BEFD+T has a nominal switching current limit of 1.8A, confirmed in Table 1 of the datasheet for all B/D variants including MAX77827BEFD+T. This value defines the peak inductor current during normal operation and determines maximum achievable output current in buck and boost modes - e.g., up to 900mA in boost mode at 3.0V_IN/3.3V_OUT. The 1.8A ILIM is factory-set and not user-adjustable.

Does MAX77827BEFD+T support adjustable output voltage, and how is it configured?

Yes, MAX77827BEFD+T supports resistor-programmable output voltage from 2.3V to 5.3V via the SEL pin. A single external resistor connected between SEL and AGND sets VOUT according to Table 2 - for example, 47.5kΩ yields 3.4V. The IC measures this resistance during startup and configures its internal reference accordingly; 1% tolerance resistors are required to maintain ±1% output accuracy across temperature.

What package type is used for MAX77827BEFD+T, and what are its thermal characteristics?

MAX77827BEFD+T uses the 2.5mm × 2.5mm, 14-lead FC2QFN package (code F142A2F+1) with exposed thermal pad. On a standard four-layer PCB, its junction-to-ambient thermal resistance (θ_JA) is 63.4°C/W. This enables reliable operation up to +125°C junction temperature with appropriate copper pour and thermal vias - critical for sustained 900mA boost-mode loads in sealed enclosures.

How does the POK (Power-OK) function work on MAX77827BEFD+T?

The POK pin on MAX77827BEFD+T is an open-drain output requiring an external pull-up resistor. It asserts high-impedance (logic high) when VOUT rises above 92.5% of the target voltage, and pulls low when VOUT falls below 90%. This ±2.5% hysteresis prevents chatter during transient events. POK provides direct power-good signaling to microcontrollers for safe boot sequencing and fault detection without additional comparators.

Can MAX77827BEFD+T operate with input voltages below 2.6V?

Yes, MAX77827BEFD+T supports an input voltage range of 1.8V to 5.5V, as explicitly stated in the Electrical Characteristics table for "A and D options". Since MAX77827BEFD+T belongs to the B/D variant group per Table 1, its valid VIN range remains 1.8V–5.5V - enabling full utilization of 1-cell Li-ion batteries down to 2.0V cutoff, unlike some competing regulators limited to ≥2.6V minimum input.