MAX471 3A Voltage detection Current detection module

Description

The MAX471 Voltage and Current Detection Module is a compact, high-side sensing board built around the Maxim MAX471 precision bidirectional current-sense amplifier. It is designed to simultaneously monitor the voltage and current of a DC load, making it a practical choice for battery monitoring, solar panel diagnostics, portable power systems, and general energy management projects. The module integrates a precision 35 mΩ internal sense resistor, allowing it to measure currents up to ±3A without external shunts . A resistive divider on the voltage detection pin scales the input voltage down by a factor of 5, so the module can measure DC voltages up to 25V when used with a 5V microcontroller (or up to 16.5V with a 3.3V system) . The board provides separate analog outputs for current (AT) and voltage (VT), which connect directly to the ADC pins of an Arduino, ESP32, or similar controller. The MAX471 also includes a SIGN output (available on some board variants) that indicates current flow direction, enabling charge/discharge monitoring in battery applications . This module is well-suited for individual makers building power monitors and for business purchasers seeking a cost-effective, high-side sensing solution for equipment diagnostics and portable power systems.

Features

• Simultaneous Voltage & Current Sensing: Provides separate analog outputs for load current (AT) and input voltage (VT), allowing real-time power calculation without additional sensors .

• High-Side Current Sensing: Monitors the positive power line without breaking the ground path, which is important for battery-powered systems and smart battery chargers .

• Bidirectional Current Measurement: Measures both charge and discharge currents across a ±3A range, with a SIGN output on supported board variants to indicate current direction .

• Precision Internal Sense Resistor: Integrates a 35 mΩ sense resistor with 2% accuracy over the full operating temperature range, eliminating the need for external shunt wiring .

• Onboard Voltage Divider: Scales the measured voltage by 1/5, enabling safe connection to 5V microcontroller ADCs for voltages up to 25V .

• Wide Supply Voltage Range: Operates from 3V to 36V, compatible with a broad range of battery and DC power systems .

• Low Power Consumption: Draws less than 100 µA during normal operation and includes a shutdown mode for battery-sensitive applications .

Technical Specifications