Analog Devices Inc./Maxim Integrated MAX44286WAZS+T

Overview

MAX44286WAZS+T from Maxim Integrated is a zero-drift, high-side current-sense amplifier with 200V/V fixed gain, 30µV max input offset voltage, 0.23% max gain error, and 12.5µA supply current at +25°C. It operates from 1.6V to 5.5V common-mode input range over –40°C to +125°C and is designed for precision battery-current monitoring in space-constrained portable medical devices and smartphones.

For engineers reviewing the MAX44286WAZS+T datasheet, MAX44286WAZS+T pinout, MAX44286WAZS+T application, or MAX44286WAZS+T equivalent, key selection criteria include ultra-low offset drift (≤300nV/°C), 4-bump WLP package footprint (0.78mm × 0.78mm × 0.35mm), guaranteed CMRR ≥120dB, and compatibility with 1.6V battery monitoring without auxiliary supply rails.

Technical Context

The MAX44286WAZS+T implements autozeroing architecture to achieve near-zero input offset drift across temperature and time, enabling stable nA-level current detection. Its supply voltage is shared with the RS+ pin, eliminating need for separate V_CC, and its internal resistor network (R_IN = 10kΩ, R_G = 50kΩ, R_A = 12.5kΩ, R_B = 487.5kΩ) sets the 200V/V gain per Table 1.

It delivers 200kHz gain-bandwidth product with 0.08V/µs slew rate and 66nV/√Hz input voltage noise at 1kHz. Output swing is referenced to RS+, limiting V_OUT(MAX) to V_RS+(MIN) – V_SENSE(FS) – V_OH, supporting full-scale sense voltage up to 98mV when V_RS+ = 5.5V.

Key Specifications

Pinout & Package

MAX44286WAZS+T uses a 4-bump wafer-level package (WLP) measuring 0.78mm × 0.78mm × 0.35mm, with solder bumps arranged in a 2×2 grid. The package requires no external decoupling beyond 0.1µF between RS+ and GND per typical application circuit.

Key Features

Applications

Equivalent & Alternatives

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

Compared with INA219BIDR and MAX40086AUB+, the MAX44286WAZS+T uniquely balances ultra-low power (12.5µA), wide 1.6V–5.5V common-mode support, and AEC-Q200-compatible +125°C operation in a 0.6mm² footprint - making it optimal for thermally constrained, battery-gauging-critical portable designs.

Availability

MAX44286WAZS+T is available at Aetrix Electronics and suitable for smartphone battery management, portable medical telemetry, and USB-C power adapter design requiring stable component supply, RoHS-compliant packaging, and long-term lifecycle continuity.

Supply support for MAX44286WAZS+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, designs precision analog, mixed-signal, and power-management ICs for demanding industrial, automotive, and portable applications.

The MAX44286 family targets ultra-low-power, high-accuracy current sensing in space-constrained battery-operated systems - emphasizing zero-drift performance, minimal supply current, and direct integration with single-cell Li-ion rails.

FAQ

What is the maximum sense voltage range supported by the MAX44286WAZS+T?

The MAX44286WAZS+T supports a full-scale sense voltage (V_SENSE(FS)) up to 98mV when V_RS+ = 5.5V, calculated as (V_RS+ – 0.6V)/200. At lower supply voltages, the linear range contracts proportionally - e.g., at V_RS+ = 3.6V, V_SENSE(FS) = 15mV. This is defined in Note 4 of the Electrical Characteristics table and verified across –40°C to +125°C.

Does the MAX44286WAZS+T require an external power supply pin?

No, the MAX44286WAZS+T does not require a separate V_CC pin. Its operating supply is derived directly from the RS+ terminal, which serves both as the high-side current-sense input and the power rail. This eliminates routing complexity and reduces PCB layer count in compact portable designs using the MAX44286WAZS+T.

How is the 200V/V gain implemented internally in the MAX44286WAZS+T?

The MAX44286WAZS+T achieves 200V/V gain via a precision internal resistor network: R_IN = 10kΩ, R_G = 50kΩ, R_A = 12.5kΩ, and R_B = 487.5kΩ (per Table 1). These laser-trimmed thin-film resistors set the gain ratio without external components, ensuring 0.23% max gain error and stable performance across temperature and time.

Can the MAX44286WAZS+T be used for bidirectional current sensing?

Yes - while the MAX44286WAZS+T itself is unidirectional, two units can be configured in parallel (one sensing high-side, one low-side) to derive bidirectional current flow. As shown in Figure 1 of the datasheet, differential outputs referenced to GND enable accurate charge/discharge separation in battery fuel gauging applications using the MAX44286WAZS+T.

What layout practices are critical for maintaining MAX44286WAZS+T accuracy?

Kelvin (four-terminal) connections to the sense resistor are mandatory to eliminate parasitic trace resistance errors. A 0.1µF ceramic capacitor must be placed between RS+ and GND close to the MAX44286WAZS+T bumps. Digital signals must be routed away from RS+/RS− traces, and a solid ground plane beneath the WLP is required to control board leakage and thermocouple-induced offset - all specified in the Applications Information section.