Analog Devices Inc./Maxim Integrated MAX40204ANA+T

Overview

MAX40204ANA+T from Analog Devices is a high-precision, bidirectional, high-side current-sense amplifier (CSA) with -0.1V to 36V input common-mode range, 2μV typical input offset voltage, and pin-programmable gain (10V/V or 100V/V). It supports unidirectional/bidirectional sensing via REF input and operates from 1.7V to 5.5V supply, consuming only 21μA - enabling accurate battery-current monitoring in portable medical instruments and smart handheld devices.

For engineers reviewing the MAX40204ANA+T datasheet, MAX40204ANA+T pinout, MAX40204ANA+T application, or MAX40204ANA+T equivalent, this device delivers ultra-low offset drift (50nV/°C), 0.05% gain error, on-the-fly gain switching, and dual-package availability (8-bump WLP and 8-pin TDFN) for space-constrained, high-reliability power management designs.

Technical Context

The MAX40204ANA+T employs a capacitive-coupled chopper instrumentation amplifier (CCIA) architecture to achieve 2μV input offset and 50nV/°C tempco - critical for stable low-current measurement across -40°C to +125°C. Its GAIN pin directly selects between 10V/V and 100V/V without external components, enabling dynamic full-scale adaptation during operation.

REF input sets output reference level: grounded for unidirectional sensing (0V–VDD output swing), or at VDD/2 for bidirectional operation (±VDD/2 output swing relative to REF). Input bias current is limited to 20nA max, supporting high-impedance sense resistor networks and minimizing error in precision systems.

Key Specifications

Pinout & Package

MAX40204ANA+T is packaged in an 8-pin TDFN (2mm × 2mm, exposed pad), pin-compatible with the WLP variant but optimized for thermal performance and manufacturability in volume production. The exposed pad must be connected to a solid ground plane for electrical integrity and thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA226AIDGST and MAX40010ATA+T, the MAX40204ANA+T uniquely combines pin-programmable gain, 2μV offset, and analog output in an 8-pin TDFN - delivering superior resolution for variable-load systems without sacrificing analog design simplicity or thermal efficiency.

Availability

MAX40204ANA+T is available at Aetrix Electronics and suitable for battery management systems, portable medical instrumentation, smartphone power delivery, and industrial PLC I/O modules requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MAX40204ANA+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 semiconductors, serving precision measurement, industrial automation, and healthcare markets since 1965.

The MAX40204ANA+T belongs to Analog Devices' precision current-sense amplifier product line, engineered specifically for high-accuracy, low-power, wide common-mode current monitoring in battery-powered and safety-critical embedded systems.

FAQ

What is the maximum sense voltage supported by MAX40204ANA+T at 100V/V gain?

The MAX40204ANA+T supports a maximum sense voltage (VSENSE) of 17mV at 100V/V gain when VDD = 1.7V, and 55mV when VDD = 5.5V, per Table 2 in the datasheet. Exceeding these limits risks output saturation or reduced linearity. For example, with VDD = 3.3V and 100V/V gain, the practical full-scale VSENSE is ~33mV - corresponding to 3.3V output swing referenced to REF.

How does the REF pin configure bidirectional sensing in MAX40204ANA+T?

In MAX40204ANA+T, connecting REF to VDD/2 configures bidirectional operation: positive VSENSE (RS+ > RS-) produces VOUT > VREF, while negative VSENSE produces VOUT < VREF. The output voltage is centered at VREF, enabling single-supply ADCs to resolve both charge and discharge currents. This differs from unidirectional mode (REF = GND), where VOUT ≥ 0V only.

Can MAX40204ANA+T operate with a 1.7V supply and still achieve full 100V/V gain accuracy?

Yes - the MAX40204ANA+T is fully specified from 1.7V to 5.5V. At 1.7V supply, it maintains 100V/V gain with 0.05% gain error and 2μV offset, though the maximum usable VSENSE drops to 17mV (per Table 2). Output swing remains rail-to-rail relative to REF, ensuring compatibility with low-voltage ADCs in energy-constrained designs.

What is the recommended PCB layout practice for RS+ and RS- pins on MAX40204ANA+T?

Use Kelvin (4-terminal) connections for the sense resistor: route dedicated force and sense traces directly to RS+ and RS-, avoiding shared copper paths. Keep RS+/RS- traces matched in length and impedance, minimize loop area, and place the resistor close to the MAX40204ANA+T package. Avoid routing near noisy signals (e.g., switching nodes) to prevent common-mode coupling that degrades CMRR.

Does MAX40204ANA+T require external filtering for stable operation in noisy industrial environments?

While the MAX40204ANA+T features inherent chopper-based noise rejection, external RC filtering is recommended: a 50Ω resistor + 22nF capacitor on the OUT pin provides 4kHz -3dB bandwidth to suppress high-frequency switching noise. For input protection, differential filtering (RIN/CIN across RS+/RS-) with RIN ≤ 50Ω prevents gain error shift and maintains <1μV added offset - as validated in the Applications Information section.