Analog Devices Inc./Maxim Integrated MAX17634CATP+T

Overview

MAX17634CATP+T from Maxim Integrated is a high-efficiency, synchronous step-down DC-DC converter with integrated high-side and low-side MOSFETs, delivering up to 4.25A output current across a 4.5V–36V input range. It features adjustable output voltage (0.9V to 90% of VIN), ±1.3% feedback regulation accuracy over –40°C to +125°C, and peak-current-mode control architecture. Designed for industrial point-of-load regulation, it enables compact designs via 400kHz–2.2MHz programmable switching frequency and internal compensation.

For engineers reviewing the MAX17634CATP+T datasheet, MAX17634CATP+T pinout, MAX17634CATP+T application, or MAX17634CATP+T equivalent, key selection criteria include its adjustable output configuration (vs. fixed-output A/B variants), EXTVCC-supported efficiency optimization, hiccup-mode overload protection, and TQFN-20 (4mm × 4mm) thermal performance with θ_JA = 26°C/W.

Technical Context

The MAX17634CATP+T implements peak-current-mode control with an internal transconductance error amplifier, slope compensation generator, and PWM comparator. Its MODE/SYNC pin selects between PFM (pulse-skipping), DCM (discontinuous conduction), or forced PWM operation-enabling >94% peak efficiency and enhanced light-load performance without external loop compensation.

It integrates dual nMOS power switches (R_DS(on)H = 60–115mΩ, R_DS(on)L = 37–73mΩ), a 5V INTVCC LDO, and auxiliary EXTVCC input for reduced conduction loss when V_OUT = 5V. Built-in features include monotonic soft-start (via SS pin), open-drain RESET with FB-based monitoring, and programmable EN/UVLO threshold (1.19V–1.26V rising).

Key Specifications

Pinout & Package

MAX17634CATP+T is housed in a thermally enhanced 20-pin TQFN package (4mm × 4mm, 0.5mm pitch) with exposed pad (EP) for optimal thermal dissipation (θ_JA = 26°C/W on multilayer board). The EP must be soldered to SGND with ≥6 thermal vias.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down DC-DC converter applications.

Compared with LM5164QPWPRQ1 and TPS54560BQDDARQ1, MAX17634CATP+T provides superior light-load efficiency via PFM/DCM modes, integrated EXTVCC for 5V output optimization, and guaranteed ±1.3% regulation accuracy across full industrial temperature range - critical for precision analog and high-reliability embedded systems.

Availability

MAX17634CATP+T is available at Aetrix Electronics and suitable for industrial control power supplies, base station power supplies, distributed supply regulation, and high-voltage single-board systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MAX17634CATP+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 industrial, communications, and computing applications.

The MAX17634x family targets high-voltage industrial point-of-load conversion, emphasizing thermal robustness, wide input range, and simplified design through integrated MOSFETs and internal compensation.

FAQ

What output voltage range does the MAX17634CATP+T support?

The MAX17634CATP+T supports an adjustable output voltage from 0.9V up to 90% of the input voltage (VIN), set via an external resistor divider on the FB pin. This enables precise regulation for common logic rails including 1.2V, 1.8V, 2.5V, 3.3V, and 5V without changing the IC. Unlike the fixed-output MAX17634A (3.3V) and MAX17634B (5V), the MAX17634CATP+T variant provides full flexibility across the entire family's operating range.

How does the MODE/SYNC pin configure operation modes on the MAX17634CATP+T?

The MODE/SYNC pin on the MAX17634CATP+T selects among three operating modes: open for PFM (pulse-frequency modulation), grounded for forced PWM (constant frequency), or tied to INTVCC for DCM (discontinuous conduction mode). In PFM mode, the device skips pulses at light loads to maximize efficiency; in PWM mode, it maintains constant frequency regardless of load; in DCM mode, it operates in discontinuous conduction at light loads while retaining PWM at heavy loads. External clock synchronization is supported only in PWM or DCM modes.

What is the purpose of the EXTVCC pin on the MAX17634CATP+T?

The EXTVCC pin on the MAX17634CATP+T accepts an external 4.56V–4.84V supply (typically the regulated 5V output) to power the internal gate driver and bias circuitry, reducing losses in the INTVCC LDO and improving overall efficiency by up to 2–3% at full load. When not used, EXTVCC must be connected to SGND. This feature is especially beneficial in 5V-output configurations where the output voltage aligns with the EXTVCC switchover threshold.

Does the MAX17634CATP+T include built-in protection features?

Yes, the MAX17634CATP+T integrates multiple protection features: hiccup-mode overload protection (self-recovering short-circuit response), overtemperature shutdown (165°C trip with 10°C hysteresis), programmable EN/UVLO for input brown-out detection, and built-in output-voltage monitoring with open-drain RESET assertion when FB drops below 92% of regulation. These features ensure robust operation in industrial environments without requiring external supervision circuitry.

What package type and thermal characteristics does the MAX17634CATP+T use?

The MAX17634CATP+T uses a 20-pin TQFN package (4mm × 4mm, 0.5mm pitch) with exposed thermal pad (EP). On a standard four-layer PCB, its junction-to-ambient thermal resistance (θ_JA) is 26°C/W, and junction-to-case (θ_JC) is 2°C/W. The EP must be soldered to SGND with ≥6 thermal vias to achieve rated performance. This package enables compact, high-power-density designs while maintaining safe junction temperatures up to +150°C.