Analog Devices Inc./Maxim Integrated MAX16938ATESB/V+T

Overview

MAX16938ATESB/V+T from Maxim Integrated is a 2.5A, 3.5V–36V input, current-mode synchronous step-down converter with integrated high-side and low-side MOSFETs, fixed 5V output (±2% accuracy), 28µA no-load quiescent current, and resistor-programmable switching frequency up to 2.2MHz - designed for automotive power rails in navigation head units and RF-sensitive infotainment systems.

For engineers reviewing the MAX16938ATESB/V+T datasheet, MAX16938ATESB/V+T pinout, MAX16938ATESB/V+T application, or MAX16938ATESB/V+T equivalent, key selection criteria include AEC-Q100 qualification, 98% max duty cycle for cold-crank support, 180° out-of-phase SYNCOUT for cascaded supplies, tight 105% overvoltage protection threshold, and FPWM/skip mode selectability via FSYNC pin.

Technical Context

The MAX16938ATESB/V+T implements current-mode control with cycle-by-cycle current limiting and automatic LX slew-rate adjustment (4ns at >1.1MHz) to balance EMI and efficiency. Its dual supply inputs (SUP/SUPSW) enable robust operation during 42V load-dump transients while maintaining regulation down to 3.5V input.

It integrates a 5V BIAS LDO (4.7–5.4V output, ±650mV UVLO hysteresis) that powers internal circuitry until OUT reaches regulation, then transitions to OUT-supplied bias above 100mA load. The PGOOD output asserts at 95% VFB and deasserts at 92% VFB with 10–50µs debounce.

Key Specifications

Pinout & Package

MAX16938ATESB/V+T is housed in a 16-pin TSSOP-EP package with exposed thermal pad (EP) connected to PGND. The package supports high-power dissipation (2088.8mW at +70°C, θ_JA = 38.3°C/W) and requires soldering per JEDEC JESD22-A113 standard.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16936ATESB/V+T, the MAX16938ATESB/V+T offers tighter 105% OVP for enhanced system safety, while the LMQ66430QRNXTQ1 trades integration for lower IQ and higher current rating - making it suitable for non-cascaded, high-efficiency 5V rails without auxiliary bias requirements.

Availability

MAX16938ATESB/V+T is available at Aetrix Electronics and suitable for automotive infotainment, telematics, and RF transceiver power applications requiring stable component supply, AEC-Q100 compliance, and long-term production continuity.

Supply support for MAX16938ATESB/V+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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for automotive, industrial, and communications markets.

The MAX16936/MAX16938 product line delivers highly integrated, AEC-Q100-qualified DC-DC converters targeting automotive power systems needing wide VIN, low IQ, and robust transient handling - especially for infotainment, ADAS, and telematics modules.

FAQ

What is the overvoltage protection threshold of the MAX16938ATESB/V+T?

The MAX16938ATESB/V+T features a fixed overvoltage protection threshold of 105% of the nominal output voltage - for its 5V fixed output, this equals 5.25V (monitored at the FB pin). This tighter threshold compared to the MAX16936 (107%) reduces risk of damage to downstream 5V logic components during transients. The protection forces the high-side switch off and low-side switch on until negative current limit is reached, then disables both switches.

How does the MAX16938ATESB/V+T support automotive cold-crank conditions?

The MAX16938ATESB/V+T supports cold-crank by operating up to 98% duty cycle, enabling regulation even when input drops to 3.5V while maintaining 5V output. Its dual supply inputs (SUP and SUPSW) remain functional down to this level, and the internal BIAS LDO sustains control circuitry until OUT reaches regulation. This behavior is validated across the full -40°C to +125°C automotive temperature range and is integral to its AEC-Q100 qualification.

Can the MAX16938ATESB/V+T be synchronized to an external clock?

Yes, the MAX16938ATESB/V+T can be synchronized to an external clock applied to the FSYNC pin. It accepts frequencies from 1.8MHz to 2.6MHz (±20% of internal FOSC) with minimum pulse width of 100ns. Synchronization occurs within one cycle; if the external clock is absent for more than two cycles, the device reverts to its internal oscillator. Note: spread-spectrum modulation is disabled during external sync.

What is the role of the BIAS pin on the MAX16938ATESB/V+T?

The BIAS pin on the MAX16938ATESB/V+T outputs a regulated 5V (4.7–5.4V) linear supply that powers internal analog circuitry. It is bypassed with a 1µF ceramic capacitor to AGND. When the output voltage is set between 3V and 5.5V, BIAS powers the IC until OUT reaches regulation and load exceeds 100mA, after which OUT supplies internal power and BIAS shuts down - improving light-load efficiency.

Does the MAX16938ATESB/V+T require an external Schottky diode?

Yes, the MAX16938ATESB/V+T requires an external Schottky diode connected between LX and PGND. Although it integrates high-side and low-side MOSFETs, the diode supports the entire load range - particularly during light-load skip mode and transient recovery - improving efficiency and ensuring reliable operation where body diode conduction would otherwise dominate.