Analog Devices Inc./Maxim Integrated MAX22212AUI+T

Overview

MAX22212AUI+T 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 precision motion systems requiring accurate phase-current limiting and compact thermal design.

For engineers reviewing the MAX22212AUI+T datasheet, MAX22212AUI+T pinout, MAX22212AUI+T application, or MAX22212AUI+T equivalent, this page delivers verified electrical specs, real-world decay-mode behavior, ISEN current monitor scaling, HFS logic impact on accuracy, and TQFN32 package thermal performance - all critical for motor-control PCB layout and closed-loop algorithm integration.

Technical Context

The MAX22212AUI+T implements a fully integrated H-bridge with internal charge pump (VCP), 1.8V LDO (VDD), and sinusoidal 4-bit DAC for dynamic ITRIP adjustment. Its current regulation loop uses non-dissipative integrated current sensing (ICS) to compare bridge current against a user-set threshold, triggering fixed t_OFF-based decay enforcement.

Four decay modes - Slow, Fast, and two Mixed variants - are selected via DECAY1/DECAY2 logic inputs; HFS input scales full-scale current by 50% and doubles low-side R_ON to improve low-current regulation accuracy. Fault reporting occurs via open-drain FAULT and CDR pins, synchronized with OCP, UVLO, and TSD events.

Key Specifications

Pinout & Package

MAX22212AUI+T is packaged in a 32-pin TQFN (5mm × 5mm, exposed pad), optimized for thermal dissipation (θ_JA = 29°C/W on 4-layer board). Pin functions are validated per Analog Devices' official TQFN pin configuration diagram (Rev 1, Jan 2024).

Key Features

Applications

Equivalent & Alternatives

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

Compared with DRV8876PWPR and TB9051FTG, MAX22212AUI+T delivers superior current regulation fidelity via its sinusoidal 4-bit DAC and four decay modes, while eliminating external shunts - reducing BOM count and improving long-term accuracy in space-constrained industrial motion systems.

Availability

MAX22212AUI+T is available at Aetrix Electronics and suitable for brushed DC motor control, stepper half-bridge drivers, solenoid actuation, and latched valve systems requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for MAX22212AUI+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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving industrial, automotive, communications, and healthcare markets with precision power and motion-control solutions.

The MAX22212 belongs to Analog Devices' high-current motor driver product line, engineered specifically for compact, thermally efficient brushed DC and stepper half-bridge applications where integrated current sensing, programmable decay, and low quiescent power are essential.

FAQ

What is the maximum continuous current the MAX22212AUI+T can deliver in a standard PCB layout?

The MAX22212AUI+T supports a recommended maximum RMS current of 4A on a standard 4-layer PCB, based on thermal characterization (θ_JA = 29°C/W). This limit ensures junction temperature remains below 125°C under typical ambient conditions. Peak current capability remains 7.6A, but sustained operation above 4A RMS requires enhanced copper area, thermal vias, or forced airflow to maintain reliability. The MAX22212AUI+T datasheet specifies this derating explicitly in the Electrical Characteristics table.

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

When HFS = high, the MAX22212AUI+T halves its full-scale current range (to 3.8A) and doubles the low-side FET R_ON, which increases the effective current-sense resolution at lower output levels. This improves regulation accuracy to ±5% down to 0.5A (vs. ±10% below 1A in full-scale mode), making the MAX22212AUI+T especially suitable for microstepping or low-torque DC motor control where fine current granularity matters.

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

The MAX22212AUI+T is a single H-bridge IC and drives only one motor winding or half of a bipolar stepper motor. To drive a full 2-phase bipolar stepper, two MAX22212AUI+T devices are required - one per phase - with coordinated control of DIN/EN/DECAY signals and shared REF/ROFF configuration. Its pinout and functional block diagram confirm dual-output architecture (OUT1A/B and OUT2A/B) for one complete bridge, not two independent half-bridges.

What is the purpose of the CDR pin on the MAX22212AUI+T, and how is it used in system design?

The CDR pin on the MAX22212AUI+T is an open-drain output that pulses low each time the internal current regulation loop activates - i.e., whenever motor current exceeds ITRIP and decay is enforced. Engineers use CDR to timestamp regulation events, validate loop responsiveness, or trigger diagnostic logging. Unlike FAULT, CDR does not indicate failure; it reflects normal, intended current-limiting behavior. Pull-up to 3.3V is required for clean MCU interrupt detection.

Does the MAX22212AUI+T require external components for gate driving, and what is the role of CP1/CP2 pins?

No, the MAX22212AUI+T integrates a charge pump with dedicated CP1 and CP2 pins to generate boosted gate-drive voltage for the high-side FETs - eliminating need for external bootstrap circuits or high-voltage gate drivers. A 22nF ceramic capacitor must be placed between CP1 and CP2, close to the device. VCP (charge-pump output) supplies the high-side gate driver, enabling full 36V operation without external boost converters or complex layout constraints.