Analog Devices Inc./Maxim Integrated MAX16935SATE/V+T

Overview

MAX16935SATE/V+T from Maxim Integrated is a 3.5A, current-mode synchronous step-down converter with integrated high-side and low-side MOSFETs, designed for automotive power supplies operating from 3.5V to 36V input. It delivers fixed 5V output with ±2% accuracy, supports resistor-programmable switching frequency from 220kHz to 2.2MHz, and achieves 28µA quiescent current in standby-enabling reliable operation in cold-crank and load-dump conditions for infotainment and ADAS subsystems.

For engineers reviewing the MAX16935SATE/V+T datasheet, MAX16935SATE/V+T pinout, MAX16935SATE/V+T application, or MAX16935SATE/V+T equivalent, key selection criteria include its AEC-Q100 qualification, 180° out-of-phase SYNCOUT for cascaded supplies, FPWM/skip mode control via FSYNC, integrated BIAS LDO, and thermal shutdown with automatic recovery-critical for automotive-grade DC/DC design validation.

Technical Context

The MAX16935SATE/V+T implements a current-mode control architecture with cycle-by-cycle current limiting and automatic LX slew-rate adjustment (4ns at >1.1MHz, 8ns at <1.1MHz) to optimize EMI-efficiency trade-offs. Its dual supply inputs (SUP and SUPSW) support wide-input operation while maintaining regulation down to 3.5V, and its 98% maximum duty cycle enables stable output during undervoltage transients.

It integrates a 5V BIAS linear regulator (4.7–5.4V output, ±2.95–3.40V UVLO), open-drain PGOOD with 95%/92% VFB thresholds, and overvoltage protection (107% for MAX16935). The device supports external synchronization (1.8–2.6MHz), spread-spectrum modulation (±6%), and soft-start (5.6–12ms), all within a -40°C to +125°C automotive temperature range.

Key Specifications

Pinout & Package

MAX16935SATE/V+T is housed in a 16-pin, 5mm × 5mm TQFN-EP package with exposed pad for thermal dissipation. Pin numbering follows standard top-view orientation with EP connected to PGND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX16939SAUE/V+T, MAX16935SATE/V+T provides higher OVP threshold for less aggressive shutdown; compared with LM61480QRNXTQ1, it delivers integrated BIAS regulation and phase-shifted SYNCOUT-reducing component count and simplifying multi-rail designs.

Availability

MAX16935SATE/V+T is available at Aetrix Electronics and suitable for automotive infotainment, ADAS camera modules, and body control units requiring stable component supply across extended temperature and voltage transients.

Supply support for MAX16935SATE/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, designs high-performance analog, mixed-signal, and power-management ICs for automotive, industrial, and communications markets.

The MAX16935/MAX16939 product line targets automotive power conversion with AEC-Q100 qualification, wide-input operation, and integrated features like SYNCOUT and BIAS LDO-specifically for infotainment, telematics, and ADAS subsystems.

FAQ

What is the maximum duty cycle supported by the MAX16935SATE/V+T?

The MAX16935SATE/V+T supports a maximum duty cycle of 98%, enabling stable regulation during severe undervoltage transients such as automotive cold-crank events where input voltage drops to 3.5V. This capability ensures continuous operation without dropout when stepping down to 5V output, and is confirmed in the Electrical Characteristics table under "Maximum Duty Cycle" with value "98%". The high duty cycle is achieved through optimized internal switch timing and low dropout design.

Does the MAX16935SATE/V+T require an external Schottky diode despite having integrated MOSFETs?

Yes, the MAX16935SATE/V+T requires an external Schottky diode connected between LX and AGND, as explicitly stated in both the General Description and Detailed Description sections. Although it integrates high-side and low-side MOSFETs, the diode is necessary to support the full 3.5A load range and improve efficiency-particularly during light-load skip mode and transient conditions. The datasheet specifies this requirement unambiguously and shows the diode in all typical application circuits.

How does the FSYNC pin control operating mode in the MAX16935SATE/V+T?

The FSYNC pin on the MAX16935SATE/V+T selects between skip mode and forced-PWM (FPWM) mode: connecting FSYNC to AGND enables skip mode for lowest quiescent current, while connecting it to BIAS or an external clock forces FPWM operation for constant frequency and minimal EMI variation. This behavior is documented in the Applications Information section and verified in the Pin Descriptions table. The device synchronizes to an external clock within one cycle and reverts to internal oscillation if the clock is absent for more than two cycles.

What is the purpose of the SYNCOUT pin on the MAX16935SATE/V+T?

The SYNCOUT pin on the MAX16935SATE/V+T provides an open-drain, 180° out-of-phase clock signal relative to the internal oscillator, enabling phase-interleaved cascaded power supplies. When used with a second MAX16935/MAX16939, it reduces input and output ripple current by up to 70%, allowing smaller input capacitors and improved thermal performance. This feature is detailed in the Benefits and Features section and confirmed in the Pin Descriptions table, where SYNCOUT is defined as "Open-Drain Clock Output" with explicit phasing specification.

Is the MAX16935SATE/V+T AEC-Q100 qualified and what grade does it meet?

Yes, the MAX16935SATE/V+T is AEC-Q100 qualified and operates over the full automotive temperature range of -40°C to +125°C, as stated in the General Description and Applications sections. The datasheet confirms qualification under "Robust Performance Supports Wide Range of Automotive Applications" and lists the operating temperature range in Absolute Maximum Ratings. No grade designation (e.g., Grade 0/1/2) is specified in the provided material, but the -40°C to +125°C range aligns with AEC-Q100 Grade 1 requirements for passenger compartment applications.