Analog Devices Inc./Maxim Integrated MAX16936SAUEB/V+

Overview

MAX16936SAUEB/V+ from Maxim Integrated is a 2.5A current-mode step-down DC-DC converter with integrated high-side and low-side MOSFETs, designed for automotive power rails requiring 3.5V–36V input, 5V/3.3V fixed or 1V–10V adjustable output, 28µA no-load quiescent current, and AEC-Q100 qualification. It enables FPWM or skip-mode operation via FSYNC and supports 98% duty cycle during cold-crank transients in navigation head units.

For engineers reviewing the MAX16936SAUEB/V+ datasheet, MAX16936SAUEB/V+ pinout, MAX16936SAUEB/V+ application, or MAX16936SAUEB/V+ equivalent, key selection criteria include its 220kHz–2.2MHz resistor-programmable switching frequency, 180° out-of-phase SYNCOUT for cascaded supplies, ±2% fixed-output accuracy, 42V load-dump tolerance, and thermal shutdown with automatic recovery.

Technical Context

The MAX16936SAUEB/V+ implements current-mode control with cycle-by-cycle current limiting and automatic LX slew-rate adjustment-4ns rise time above 1.1MHz, 8ns below-to optimize EMI vs. efficiency trade-offs. Its dual supply inputs (SUP/SUPSW) decouple logic and power-switch biasing, enabling stable operation down to 3.5V input while supporting 42V transient tolerance.

It integrates a 5V BIAS LDO (4.7–5.4V output, 10mA max), power-good monitoring with 92–95% VFB thresholds, and overvoltage protection at 107% of regulation (MAX16936 variant). The FSYNC pin selects between skip mode (FSYNC = AGND) and forced-PWM (FSYNC = BIAS or external clock), with synchronization acquisition within one cycle and ±20% external clock tolerance.

Key Specifications

Pinout & Package

MAX16936SAUEB/V+ is housed in a 16-pin TSSOP-EP (exposed pad) package with 0.65mm pitch, optimized for thermal dissipation in automotive PCB layouts. The exposed pad must be soldered to a large-area PGND copper plane but cannot serve as the sole ground connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16936SAUEB/V+, MAX16938SAUEB/V+ provides tighter overvoltage protection at identical cost and footprint, while LM61480QRPGRQ1 trades away critical automotive features (SYNCOUT, BIAS, AEC-Q100 OVP spec) for higher current and lower quiescent current-making it unsuitable as a drop-in replacement.

Availability

MAX16936SAUEB/V+ is available at Aetrix Electronics and suitable for automotive navigation systems, industrial PLCs, RF transceiver power supplies, and camera ECUs requiring stable component supply across extended temperature and transient-voltage conditions.

Supply support for MAX16936SAUEB/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 high-performance analog and mixed-signal ICs for automotive, industrial, and communications markets, emphasizing robustness, integration, and AEC-Q100 compliance.

The MAX16936/MAX16938 product line targets automotive power management with emphasis on cold-crank resilience, load-dump survival, and EMI-controlled switching-enabling compact, reliable DC-DC solutions for infotainment, ADAS, and body electronics.

FAQ

What is the maximum input voltage transient the MAX16936SAUEB/V+ can withstand?

The MAX16936SAUEB/V+ is rated for 42V load-dump transients lasting ≤1 second per ISO 7637-2 Pulse 5a, with no latch-off or damage. This is validated by absolute maximum ratings (VSUP_LD = 42V) and AEC-Q100 stress testing. The device remains operational during 36V continuous input and recovers automatically after transient clearance. MAX16936SAUEB/V+ incorporates internal clamping and thermal protection to sustain these events without external TVS diodes in most implementations.

Does the MAX16936SAUEB/V+ require an external Schottky diode, and why?

Yes, the MAX16936SAUEB/V+ requires an external Schottky diode connected from LX to PGND. Although it integrates high-side and low-side MOSFETs, the low-side FET is used only for synchronous rectification in FPWM mode-not for freewheeling in all conditions. During light-load skip mode or certain transient conditions, the external diode ensures continuous current path and prevents reverse current flow that could destabilize regulation. MAX16936SAUEB/V+ datasheet Figure 1 and "Detailed Description" explicitly mandate this diode for efficiency and stability.

How does the FSYNC pin configure skip mode versus forced-PWM mode on the MAX16936SAUEB/V+?

On the MAX16936SAUEB/V+, FSYNC = AGND enables skip mode (reduced light-load IQ), while FSYNC = BIAS or an external clock ≥1.8MHz enables forced-PWM (fixed frequency, low EMI). The device detects FSYNC logic level at power-up and during runtime; if external clock disappears for >2 cycles, it reverts to internal oscillator. This dual-mode flexibility lets designers optimize MAX16936SAUEB/V+ for either efficiency (skip) or EMI (FPWM) without hardware changes.

What is the purpose of the SYNCOUT pin on the MAX16936SAUEB/V+, and how is it used?

The SYNCOUT pin on MAX16936SAUEB/V+ provides an open-drain 180° out-of-phase clock signal relative to the internal oscillator, enabling phase-interleaved operation with a second MAX16936SAUEB/V+ or compatible device. When two converters are cascaded with SYNCOUT of the first driving FSYNC of the second, input/output ripple current is reduced by ~30%, allowing smaller input capacitors and lower EMI. MAX16936SAUEB/V+ datasheet specifies a 100Ω–1kΩ pull-up resistor for 2MHz operation.

Can the MAX16936SAUEB/V+ operate with a 3.5V input, and what happens during cold-crank?

Yes, MAX16936SAUEB/V+ operates down to 3.5V input and is specifically designed for cold-crank scenarios. When input drops below VOUT (e.g., 6V → 5V), it enters high-duty-cycle mode (up to 98%) to maintain regulation. The device monitors off-time continuously and forces low-side FET conduction every 12µs to sustain output. This behavior is guaranteed across −40°C to +125°C and is validated in "DIPS AND DROPS TEST" (Figure toc18) of the MAX16936SAUEB/V+ datasheet.