Analog Devices Inc./Maxim Integrated MAX17243ETPA+T

Overview

The MAX17243ETPA+T from Maxim Integrated is a 3A, synchronous step-down DC-DC converter with integrated MOSFETs, operating from 3.5V to 36V input and delivering fixed 3.3V/5V or adjustable 1V–10V output. It features 93% peak efficiency, 15µA quiescent current in standby, and 2.2MHz switching frequency with spread-spectrum EMI reduction-used in industrial point-of-load regulation where high efficiency and compact layout are critical.

For engineers reviewing the MAX17243ETPA+T datasheet, MAX17243ETPA+T pinout, MAX17243ETPA+T application, or MAX17243ETPA+T equivalent, key selection criteria include its 3A output capability, 99% max duty cycle for dropout operation, PFM/PWM mode flexibility, integrated BIAS regulator, and 20-pin TQFN (5mm × 5mm) package with exposed pad for thermal management.

Technical Context

This device implements current-mode control with selectable PWM (fixed-frequency) or PFM (pulse-skipping) operation-enabling constant switching frequency under load sensitivity constraints or ultra-low quiescent current at light loads. The internal 5V BIAS regulator powers analog circuitry and supports external capacitor bypassing for stability.

It integrates high-side (60–140mΩ) and low-side (35–70mΩ) MOSFETs, uses resistor-programmable FOSC (220kHz–2.2MHz), supports external clock synchronization via FSYNC, and includes cycle-by-cycle current limiting, thermal shutdown with 15°C hysteresis, and 42V transient protection on SUP/SUPSW pins.

Key Specifications

Pinout & Package

MAX17243ETPA+T is housed in a 20-pin, 5mm × 5mm TQFN package with exposed thermal pad (EP), rated for –40°C to +85°C ambient operation. The EP must be soldered to a large contiguous copper ground plane for effective heat dissipation and cannot serve as the sole ground connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX17242ETPA+T, the MAX17243ETPA+T delivers 50% more output current in the same footprint; versus LM61480RQR, it integrates bias regulation and spread-spectrum EMI control-reducing external component count and simplifying compliance testing.

Availability

MAX17243ETPA+T is available at Aetrix Electronics and suitable for industrial PLC I/O modules, automotive body control units, and smart building sensor nodes requiring stable component supply, long-lifecycle assurance, and consistent parametric performance across production batches.

Supply support for MAX17243ETPA+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, automotive, and communications applications-with emphasis on integration, reliability, and low-power operation.

The MAX1724x family targets high-efficiency, wide-input DC-DC conversion in space- and thermally constrained environments-specifically engineered for point-of-load regulation where minimal external components and robust transient response are mandatory.

FAQ

What is the maximum output current capability of the MAX17243ETPA+T?

The MAX17243ETPA+T delivers up to 3A continuous output current under specified thermal conditions (T_A ≤ +85°C, proper PCB thermal design). Its LX current limit is 3.75A (min), 5A (typ), and 6.25A (max), enabling reliable operation with margin against short-term surges. This makes the MAX17243ETPA+T suitable for powering microcontrollers, FPGAs, and peripheral ICs in industrial and automotive applications where sustained 3A loads occur.

Does the MAX17243ETPA+T support both PWM and PFM operation modes?

Yes, the MAX17243ETPA+T supports both PWM and PFM operation, selected via the FSYNC pin: connecting FSYNC to AGND enables PFM mode for highest light-load efficiency, while connecting it to BIAS or an external clock forces fixed-frequency PWM mode. This dual-mode capability allows designers to optimize for either ultra-low quiescent current (PFM) or EMI-sensitive timing-critical systems (PWM), without changing hardware-making the MAX17243ETPA+T adaptable across diverse power architectures.

What package type and thermal characteristics does the MAX17243ETPA+T use?

The MAX17243ETPA+T uses a 20-pin TQFN package measuring 5mm × 5mm with an exposed thermal pad (EP). Its junction-to-ambient thermal resistance (θ_JA) is 30°C/W on a standard four-layer JEDEC board, and junction-to-case (θ_JC) is 2°C/W. The EP must be soldered to a large contiguous copper ground plane using multiple thermal vias-this configuration ensures safe operation at full 3A load within the –40°C to +85°C ambient range, and is essential for achieving the rated 93% peak efficiency of the MAX17243ETPA+T.

How is the output voltage configured on the MAX17243ETPA+T?

The MAX17243ETPA+T supports fixed 3.3V or 5V outputs (±2% accuracy) by connecting the FB pin directly to the BIAS pin. For adjustable outputs from 1V to 10V (±1% FB accuracy), an external resistive divider is used between OUT and AGND, with FB connected to the divider midpoint. The feedback reference voltage is precisely 1.00V (±1%), and R_FB2 (to AGND) should be ≤500kΩ. This flexibility allows the MAX17243ETPA+T to serve multiple voltage rails in a single platform without redesigning the power stage.

What protection features are built into the MAX17243ETPA+T?

The MAX17243ETPA+T includes cycle-by-cycle current limiting, thermal shutdown with automatic recovery (175°C trip, 160°C restart), 42V transient protection on SUP/SUPSW pins, and overvoltage protection (107% V_OUT trip). It also features a fixed 8ms soft-start to limit inrush current and a PGOOD output that monitors regulation status with 95%/92.5% thresholds. These protections ensure robust field operation in harsh environments-making the MAX17243ETPA+T appropriate for mission-critical industrial and automotive power systems where reliability is non-negotiable.