Analog Devices Inc./Maxim Integrated MAX40056UAUA+T

Overview

The MAX40056UAUA+T from Maxim Integrated is a bidirectional current-sense amplifier optimized for PWM-driven inductive loads, featuring -0.1V to +65V input common-mode range, 10V/V fixed gain, ±5µV typical input offset voltage, and 300kHz bandwidth. It enables accurate phase-current monitoring in motor windings and solenoids with integrated 1.5V reference and overcurrent comparator.

For engineers reviewing the MAX40056UAUA+T datasheet, MAX40056UAUA+T pinout, MAX40056UAUA+T application, or MAX40056UAUA+T equivalent, key selection criteria include PWM edge recovery time (500ns), AC CMRR at ±500V/µs (60dB), rail-to-rail output swing, internal reference sourcing capability, and AEC-Q100 qualification for automotive-grade reliability.

Technical Context

The MAX40056UAUA+T employs a chopper-stabilized architecture to achieve ±5µV typical input offset voltage and <0.5% gain error over -40°C to +125°C, enabling precision measurement with low-value sense resistors. Its proprietary input stage rejects fast PWM edges up to ±500V/µs while maintaining 60dB AC CMRR at 50V common-mode voltage.

It integrates a 1.5V ±1% internal reference that offsets the output to indicate current direction and serves as threshold source for the window comparator. The REF pin sources current to external loads, eliminating noisy PCB routing of reference signals, and supports external override above 1.65V for extended full-scale output swing.

Key Specifications

Pinout & Package

MAX40056UAUA+T is housed in an 8-pin µMAX package (2.02mm × 1.4mm footprint, U8+4 code), suitable for space-constrained motor control PCBs with thermal resistance θ_JA = 206°C/W on multilayer board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar bidirectional current-sense amplifier applications.

Compared with INA240A1QDRQ1 and MAX40057FAUA+, the MAX40056UAUA+T provides optimal balance of 10V/V gain for wide dynamic range, integrated fault detection, and compact µMAX packaging-making it ideal for space-constrained, high-reliability motor control designs requiring minimal external components.

Availability

MAX40056UAUA+T is available at Aetrix Electronics and suitable for automotive motor control, industrial solenoid actuation, and battery management systems requiring stable component supply, long-term lifecycle support, and AEC-Q100 compliance.

Supply support for MAX40056UAUA+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 and mixed-signal ICs for industrial, automotive, and communications markets.

The MAX40056 family was designed specifically for robust current sensing in PWM-controlled inductive loads, emphasizing fast transient recovery, high common-mode rejection, and integrated fault protection for next-generation motor drives.

FAQ

What is the gain configuration of the MAX40056UAUA+T?

The MAX40056UAUA+T is the U-grade variant of the MAX40056 family and features a fixed 10V/V gain. This is confirmed in the Electrical Characteristics table and Applications Information section of the datasheet, where Table 1 explicitly lists MAX40056U with 10V/V gain and ±150mV to ±180mV input differential range depending on supply and reference voltage. The gain is laser-trimmed and not user-configurable.

Does the MAX40056UAUA+T support external reference override?

Yes, the MAX40056UAUA+T supports external reference override: when a voltage >1.65V is applied to the REF pin, the internal 1.5V reference is automatically disabled and the external voltage becomes the new reference. This is documented in the "Voltage Reference" section and Electrical Characteristics table (VREF_TH = 1.65V to 1.75V), enabling extended full-scale output swing for higher supply voltages like 5V.

What is the purpose of the COP and CIP pins on the MAX40056UAUA+T?

The COP (pin 2) is an active-low push-pull comparator output that asserts low during overcurrent conditions detected by the internal window comparator. The CIP (pin 7) is the comparator input used to set the lower threshold voltage via a resistor divider from REF. Together, they implement fault detection without external components-COP drives MCU interrupts directly, and CIP defines trip points with 40mV hysteresis for noise immunity.

Is the MAX40056UAUA+T suitable for automotive applications?

Yes, the MAX40056UAUA+T is AEC-Q100 qualified (Grade 1, -40°C to +125°C) and explicitly listed in the "Benefits and Features" and "Applications" sections for automotive use. Its -5V to +70V input protection, 500ns PWM edge recovery, and integrated fault comparator meet stringent requirements for electric power steering, HVAC blowers, and transmission solenoid control.

How does the MAX40056UAUA+T handle Kelvin sensing layout requirements?

The MAX40056UAUA+T supports Kelvin sensing through dedicated RS+ and RS- inputs, which are designed for 4-terminal resistor connections. The Pin Description section recommends routing Kelvin traces as close as possible to the sense resistor pads to avoid parasitic resistance errors, and Figure 4 illustrates proper force-and-sense trace separation. This ensures accurate current measurement independent of PCB trace resistance.