Analog Devices Inc./Maxim Integrated MAX22212AUI+

Overview

MAX22212AUI+ from Analog Devices is a 36V, 7.6A single H-bridge motor driver IC designed for brushed DC and stepper half-bridge control. It integrates low-R_ON FETs (0.125Ω typical total), non-dissipative current sensing, and programmable current regulation with 4 decay modes. Used in compact industrial actuators requiring precise torque control and thermal efficiency.

For engineers reviewing the MAX22212AUI+ datasheet, MAX22212AUI+ pinout, MAX22212AUI+ application, or MAX22212AUI+ equivalent, key selection criteria include integrated ICS accuracy (±5% over 1.4–6A), HFS pin-enabled current range scaling, fixed t_OFF configurability via ROFF resistor, and dual-package availability (TQFN32/TSSOP28) with verified thermal performance on 4-layer PCBs.

Technical Context

The MAX22212AUI+ implements a fully integrated gate driver with charge-pump-based high-side FET control and logic-level PWM interface (DIN1/DIN2/EN). Its sinusoidal 4-bit DAC dynamically sets ITRIP across 16 levels from zero to full-scale current, while internal current sensing eliminates external shunt resistors.

Current regulation operates via comparator-based CDR loop enforcing fixed t_OFF decay-configurable from 16μs to >120μs using ROFF-and supports Slow, Fast, and two Mixed decay modes. Fault management includes OCP (7.6A threshold), UVLO (4.0V rising), and TSD (165°C with 20°C hysteresis), all signaled via open-drain FAULT.

Key Specifications

Pinout & Package

MAX22212AUI+ is packaged in a RoHS-compliant TSSOP28 (4.4mm × 9.7mm) with exposed thermal pad (EP), optimized for manual assembly and thermal dissipation on standard PCBs. θ_JA = 24.65°C/W on 4-layer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar H-bridge motor driver applications.

Compared with TB9051FTG and DRV8876N, MAX22212AUI+ delivers superior current regulation fidelity (±5% vs ±8%), configurable decay flexibility (4 modes vs 2), and hardware-enabled dual-range operation-critical for precision stepper microstepping and battery-constrained medical devices.

Availability

MAX22212AUI+ is available at Aetrix Electronics and suitable for industrial actuators, medical pumps, automated test equipment, and smart home locks requiring stable component supply, long-lifecycle assurance, and validated thermal performance on standard PCB stacks.

Supply support for MAX22212AUI+ 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The MAX22212AUI+ belongs to Analog Devices' precision motor driver product line, engineered for space-constrained motion control systems demanding integrated current sensing, thermal resilience, and programmable decay behavior without external passive components.

FAQ

What is the maximum continuous RMS current supported by MAX22212AUI+ on a standard 4-layer PCB?

The MAX22212AUI+ recommends a maximum RMS current of 4A_RMS on a standard 4-layer PCB, based on thermal characterization showing θ_JA = 24.65°C/W. This limit ensures junction temperature remains below 125°C under worst-case ambient conditions and accounts for conduction losses in the 0.125Ω total R_ON. Exceeding this requires enhanced cooling or derating.

How does the HFS pin affect current regulation accuracy in MAX22212AUI+?

When HFS = high, the MAX22212AUI+ halves its full-scale current range (to 3.8A) and doubles the low-side FET R_ON, improving current regulation accuracy below 1A. Specifically, DITRIP2 accuracy tightens from ±10% to ±10% over 0.4–0.7A (vs ±10% over 0.8–1.4A in full-scale mode), enabling precise low-torque control in medical pumps and micro-actuators.

Can MAX22212AUI+ drive a full bipolar stepper motor, or is it limited to half-bridge operation?

The MAX22212AUI+ is a single H-bridge IC and drives only one half of a bipolar stepper motor (e.g., phase A or B). To drive a full 2-phase stepper, two MAX22212AUI+ devices are required-one per phase-with coordinated decay mode and current regulation settings. Its pinout and control logic are not designed for native 4-phase interleaving.

What external components are mandatory for basic operation of MAX22212AUI+?

Mandatory external components for MAX22212AUI+ include: (1) 1μF ceramic + 10μF electrolytic capacitors on VM, (2) 22nF flying capacitor between CP1/CP2, (3) 2.2μF capacitor on VDD, (4) pull-up resistor on FAULT, and (5) resistor from REF to GND to set IFS. ROFF and ISET resistors are optional but required for t_OFF and DAC programming.

Does MAX22212AUI+ support PWM frequencies above 100kHz, and what limits the upper bound?

Yes, MAX22212AUI+ supports PWM frequencies up to ~200kHz, limited primarily by t_DEAD = 100ns and output slew rate of 200V/μs. At higher frequencies, minimum ON/OFF times must exceed t_DEAD + t_BLK (2.8μs typical), and layout parasitics become critical. For reliable 150kHz operation, use short traces, ground plane coupling, and minimize ISEN/CDR routing length.