Analog Devices Inc./Maxim Integrated MAX16909RAUE/V+

Overview

MAX16909RAUE/V+ from Maxim Integrated is a 3A, current-mode, automotive-grade step-down DC-DC converter with integrated 70mΩ high-side MOSFET, operating from 3.5V to 36V input and delivering 5V fixed or 1V–10V adjustable output. It features 30µA standby current, 220kHz–1MHz resistor-programmable switching frequency, and operates across –40°C to +125°C for engine control units and ADAS power rails.

For engineers reviewing the MAX16909RAUE/V+ datasheet, MAX16909RAUE/V+ pinout, MAX16909RAUE/V+ application, or MAX16909RAUE/V+ equivalent, this page delivers verified electrical specs, thermal performance data, automotive transient tolerance (42V load dump), skip-mode behavior, and real-world compensation guidance - all confirmed against Maxim's official Rev 4 datasheet and TQFN package documentation.

Technical Context

The MAX16909RAUE/V+ implements constant-frequency current-mode control with internal transconductance error amplifier (gm = 900µS), 110ns minimum on-time, and 98% max duty cycle during cold-crank undervoltage events. Its dual-supply architecture separates SUP (bias regulator input) and SUPSW (high-side switch supply), enabling stable operation down to 3.5V while tolerating 42V transients.

It integrates a 5V linear regulator (BIAS) with 4.7V–5.5V output and 300mV UVLO hysteresis, plus synchronous FSYNC input accepting external clocks up to 10% above internal f_SW. Protection includes overvoltage trip at 110% V_FB, thermal shutdown at +175°C with 15°C hysteresis, and automatic-recovery overcurrent limiting.

Key Specifications

Pinout & Package

MAX16909RAUE/V+ is housed in a 16-pin TQFN package (5mm × 5mm) with exposed pad (EP), optimized for automotive thermal dissipation. The EP must be soldered to a large contiguous copper ground plane; it is not a substitute for dedicated GND pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM61480-Q1 and TPS543B20, MAX16909RAUE/V+ uniquely combines 3.5V start-up, 42V transient tolerance, 30µA standby, and FSYNC capability - making it optimal for cost-sensitive, thermally constrained automotive body electronics where analog control and reliability outweigh digital features.

Availability

MAX16909RAUE/V+ is available at Aetrix Electronics and suitable for automotive ECU power supplies, ADAS camera modules, infotainment head units, and industrial IoT gateways requiring stable component supply across extended temperature and high-reliability automotive qualification.

Supply support for MAX16909RAUE/V+ 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 automotive, industrial, and communications markets with emphasis on high-reliability, AEC-Q100-qualified components.

The MAX16909RAUE/V+ belongs to Maxim's automotive power-management portfolio, engineered specifically for harsh-environment DC-DC conversion in engine bays and ADAS subsystems where input transients, thermal stress, and low-quiescent-current operation are critical.

FAQ

What is the maximum input voltage the MAX16909RAUE/V+ can withstand during automotive load-dump events?

The MAX16909RAUE/V+ withstands 42V input transients for durations under 1 second, as specified in its Absolute Maximum Ratings and validated per ISO 7637-2 Pulse 5a testing. This rating applies to both SUP and SUPSW pins, enabling direct connection to unclamped vehicle battery rails without external TVS diodes in many implementations. The device remains functional and does not latch up during such events.

Does the MAX16909RAUE/V+ support both fixed 5V and adjustable output configurations?

Yes, the MAX16909RAUE/V+ supports both configurations. Tie FB directly to BIAS for a factory-trimmed 5V ±1.5% output. For adjustable outputs from 1V to 10V, connect an external resistor divider between OUT and GND with FB at the midpoint; the internal 1.0V feedback reference ensures accuracy across temperature. The MAX16909RAUE/V+ datasheet provides exact calculation formulas and layout guidance for both modes.

How does the MAX16909RAUE/V+ achieve 30µA quiescent current in standby mode?

The MAX16909RAUE/V+ achieves 30µA standby current by entering skip mode at light loads (<300mA), disabling most internal circuitry and powering bias circuitry from VOUT (when 3V–5.5V). This architecture avoids linear regulator dropout losses and minimizes switching activity. Measured at TA = +25°C with VOUT = 5V, the MAX16909RAUE/V+ delivers 30µA typical and 60µA maximum I_Q, enabling multi-year battery life in always-on automotive modules.

What package type and thermal characteristics apply to the MAX16909RAUE/V+?

The MAX16909RAUE/V+ uses a 16-pin TQFN package (5mm × 5mm) with exposed pad (EP), designated by the "RAUE" suffix. Its thermal resistance is 35°C/W (junction-to-ambient, JEDEC JESD51-7 multilayer board) and 2.7°C/W (junction-to-case). The EP must be soldered to a large ground plane with ≥4 thermal vias for effective heat dissipation in automotive under-hood applications up to +125°C ambient.

Can the MAX16909RAUE/V+ be synchronized to an external clock, and what are the requirements?

Yes, the MAX16909RAUE/V+ accepts external synchronization via the FSYNC pin. The external clock frequency must exceed the internal oscillator frequency by at least 10% for reliable acquisition, and the input must meet TTL/CMOS logic thresholds (V_{FSYNC_HI} ≥ 1.4V, V_{FSYNC_LO} ≤ 0.4V). Synchronization reduces EMI by aligning switching edges to system clocks - a key requirement for automotive infotainment and ADAS subsystems complying with CISPR-25.