Analog Devices Inc./Maxim Integrated MAX40204ANA+

Overview

MAX40204ANA+ 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 enables accurate low-power current monitoring in battery-powered portable systems using small sense resistors.

For engineers reviewing the MAX40204ANA+ datasheet, MAX40204ANA+ pinout, MAX40204ANA+ application, or MAX40204ANA+ equivalent, this device supports on-the-fly gain switching, unidirectional/bidirectional sensing via REF input, and operates from 1.7V–5.5V supply with only 21μA quiescent current - critical for medical instruments, smart phones, and notebook power management.

Technical Context

The MAX40204ANA+ uses a capacitive-coupled chopper instrumentation amplifier (CCIA) architecture to achieve ultra-low 2μV input offset and 50nV/°C drift, enabling sub-millivolt differential signal measurement without significant error accumulation. Its dual-gain logic interface (GAIN pin) directly controls internal gain-setting switches, allowing real-time reconfiguration between 10V/V and 100V/V without external components.

It supports both unidirectional (REF = GND) and bidirectional (REF = VDD/2) operation by shifting output reference level, while maintaining full accuracy across -40°C to +125°C. The 8-pin TDFN package integrates an exposed pad for thermal and electrical grounding, and its 20nA max input bias current minimizes error in high-impedance sensing paths.

Key Specifications

Pinout & Package

MAX40204ANA+ is packaged in an 8-pin TDFN (2mm × 2mm, package code T822+3C) with exposed pad (EP) requiring connection to solid ground plane for thermal and electrical performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA240A1QDRQ1 and MAX40010ATA+T, the MAX40204ANA+ uniquely combines pin-programmable gain, 2μV offset, and REF-based bidirectional operation in a 2mm × 2mm TDFN - enabling higher accuracy across wider current ranges without sacrificing board area or adding complexity.

Availability

MAX40204ANA+ is available at Aetrix Electronics and suitable for power management systems, portable medical devices, and notebook computer designs requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for MAX40204ANA+ 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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX40204ANA+ belongs to Analog Devices' precision current-sense amplifier product line, engineered specifically for high-accuracy, low-power, wide common-mode monitoring in battery-constrained and thermally sensitive applications.

FAQ

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

The MAX40204ANA+ supports a maximum sense voltage (VSENSE) of 55mV when VDD = 5.5V and gain = 100V/V, and 17mV when VDD = 1.7V under the same gain setting. These limits ensure linear operation and prevent output saturation - verified per Table 2 in the official datasheet. Exceeding these values risks clipping and measurement inaccuracy. The MAX40204ANA+ datasheet specifies these boundaries based on supply-dependent headroom requirements.

Can MAX40204ANA+ perform true ground-sensing (below 0V) in low-side configurations?

Yes, the MAX40204ANA+ supports true ground-sensing with an input common-mode range down to −0.1V, enabling accurate low-side current measurement even when the sense resistor is placed between load and system ground. This capability eliminates the need for level-shifting circuitry in applications like battery discharge monitoring or rail-to-rail power path analysis. The MAX40204ANA+ maintains full accuracy and stability at −0.1V common-mode, as confirmed in Absolute Maximum Ratings and Electrical Characteristics sections.

How does the REF pin configure bidirectional versus unidirectional operation in MAX40204ANA+?

In the MAX40204ANA+, connecting REF to GND configures unidirectional operation - output voltage scales from 0V upward proportional to positive current flow. Connecting REF to VDD/2 enables bidirectional operation - output centers at VDD/2, swinging above for charge current and below for discharge current. This dual-mode flexibility is implemented via internal reference routing and requires no external components. The MAX40204ANA+ datasheet confirms REF's role in defining output baseline in both Figure 1 and Figure 2.

What is the turn-on time from shutdown for MAX40204ANA+?

The MAX40204ANA+ has a guaranteed turn-on time (tEN) of 400μs - defined as the time from SHDN rising to 90% of final output voltage after exiting shutdown mode. This parameter is tested across temperature and supply conditions and appears in the Electrical Characteristics table. The fast wake-up supports responsive current monitoring in duty-cycled systems such as wearable health monitors. The MAX40204ANA+ maintains this timing regardless of gain setting or REF configuration.

Does MAX40204ANA+ require external filtering for stable operation with noisy power supplies?

Yes, the MAX40204ANA+ requires local bypassing: a 0.1μF ceramic capacitor and a 4.7μF bulk capacitor in parallel, placed as close as possible to the VDD pin and GND. This dual-capacitor network suppresses high-frequency noise and supply transients that could modulate the output or degrade PSRR. The MAX40204ANA+ datasheet explicitly mandates this configuration in the Pin Description section for Pin 7 (VDD), and omission risks increased output ripple and measurement instability.