Analog Devices Inc./Maxim Integrated MAX20003ATPB/V+C2

Overview

MAX20003ATPB/V+C2 from Maxim Integrated is a 3A synchronous buck converter with integrated high-side and low-side MOSFETs, operating from 3.5V to 36V input and delivering fixed 5V/3.3V or adjustable 1V–10V output. It features 15µA quiescent current in skip mode, 2.2MHz programmable switching frequency (via FOSC resistor), and AEC-Q100 qualification for automotive power rails in navigation units and radio head units.

For engineers reviewing the MAX20003ATPB/V+C2 datasheet, MAX20003ATPB/V+C2 pinout, MAX20003ATPB/V+C2 application, or MAX20003ATPB/V+C2 equivalent, key selection criteria include its 99% dropout duty cycle, ±1% FB accuracy for adjustable outputs, 42V load-dump protection, and spread-spectrum enablement via SPS pin for EMC-sensitive automotive designs.

Technical Context

This device implements current-mode control with internal transconductance error amplifier (g_M = 700µS), fixed 8ms soft-start, and cycle-by-cycle current limiting. Its dual-supply architecture separates SUP (bias regulator input) and SUPSW (high-side switch supply), enabling stable operation during cold-crank transients down to 3.5V.

The IC supports two operational modes: forced PWM (via FSYNC tied to BIAS or external clock) and skip mode (FSYNC to AGND), with automatic transition based on load. Spread spectrum modulation (±3% around f_SW, 110µs period at 2.2MHz) is enabled by pulling SPS high and disabled during external synchronization.

Key Specifications

Pinout & Package

MAX20003ATPB/V+C2 uses a 20-pin thermally enhanced TQFN package (5mm × 5mm, outline 21-0140) with exposed pad (EP) soldered to PGND for optimal thermal dissipation. Pin 19 is no-connect; EP must be connected to PGND and not used as sole ground path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM61480RQR and TPS543B20RTWR, MAX20003ATPB/V+C2 uniquely combines AEC-Q100 Grade 1, 42V load-dump tolerance, and hardware-based spread spectrum - making it the only option qualified for safety-critical automotive power rails without external protection circuitry.

Availability

MAX20003ATPB/V+C2 is available at Aetrix Electronics and suitable for automotive navigation systems, radio head units, and distributed power architectures requiring stable component supply across extended temperature and voltage stress conditions.

Supply support for MAX20003ATPB/V+C2 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.

The MAX20003 belongs to Maxim's automotive-qualified power portfolio, engineered specifically for harsh-environment DC-DC conversion in infotainment, ADAS, and body electronics with emphasis on low IQ, wide VIN, and EMI robustness.

FAQ

What is the maximum duty cycle supported by MAX20003ATPB/V+C2 during input undervoltage conditions?

MAX20003ATPB/V+C2 supports up to 99% duty cycle in dropout mode, enabling regulation even when input voltage drops close to output voltage - critical for automotive cold-crank events where battery voltage falls to 3.5V. This behavior is achieved by forcing the low-side FET on for 150ns every 12µs once off-time reaches 100ns, ensuring continuous output during transients. The MAX20003ATPB/V+C2 datasheet specifies this as a guaranteed feature across -40°C to +125°C.

How does the spread-spectrum function work on MAX20003ATPB/V+C2, and what is its impact on EMI?

When the SPS pin is pulled high, MAX20003ATPB/V+C2 modulates its switching frequency by ±3% around the programmed f_SW using a triangular waveform with 110µs period at 2.2MHz. This spreads energy across a narrow band, reducing peak radiated emissions by up to 10dB - a key advantage for passing CISPR 25 Class 5 tests in automotive modules. The MAX20003ATPB/V+C2 disables internal spread spectrum automatically when synchronized to an external clock via FSYNC.

Can MAX20003ATPB/V+C2 operate with a 3.3V fixed output and still deliver full 3A current?

Yes, MAX20003ATPB/V+C2 delivers full 3A continuous output at 3.3V with ±2% accuracy when FB is connected directly to BIAS. Electrical characteristics confirm 3.23V–3.37V output across -40°C to +125°C and 30mA–3A load range. The device maintains this performance with 15µA quiescent current in skip mode and supports 2.2MHz operation - verified in typical application circuits with 2.2µH inductor and 44µF output capacitance.

What is the purpose of the dual supply inputs SUP and SUPSW on MAX20003ATPB/V+C2?

SUP powers the internal bias regulator (BIAS), while SUPSW supplies the high-side gate driver - separating logic and power domains improves efficiency and transient response. During cold-crank, SUP may drop below BIAS regulation threshold, but SUPSW remains active to sustain switching. This architecture allows MAX20003ATPB/V+C2 to maintain regulation even when input falls to 3.5V, unlike single-supply buck converters that fail below their internal LDO dropout voltage.

Is MAX20003ATPB/V+C2 pin-compatible with other devices in the MAX2000x family?

MAX20003ATPB/V+C2 shares identical 20-pin TQFN package and pinout with MAX20002 variants (e.g., MAX20002ATPB/V+C2), differing only in current capability (3A vs. 2A) and LX current limit (6.25A vs. 4.16A). This enables drop-in replacement in existing layouts when higher output current is required, provided thermal design accommodates the increased power dissipation of the MAX20003ATPB/V+C2.