High-Side, Current-Sense Amplifiers with 12-Bit ADC and Op Amp/Comparator

The MAX9611/MAX9612 are high-side current-sense amplifiers with an integrated 12-bit ADC and a gain block that can be configured either as an op amp or comparator, making these devices ideal for a number of industrial and automotive applications.

The high-side, current-sense amplifiers operate over a wide 0V to 60V input common-mode voltage range. The programmable full-scale voltage (440mV, 110mV, and 55mV) of these amplifiers offers wide dynamic range, accurate current measurement, and application flexibility in choosing sense resistor values. A choice of either an internal op amp or a comparator is provided to the user. The internal amplifier can be used to limit the inrush current or to create a current source in a closed-loop system. The comparator can be used to monitor fault events for fast response.

An I2C-controlled 12-bit, 500sps analog-to-digital converter (ADC) can be used to read the voltage across the sense resistor (VSENSE), the input common-mode voltage (VRSCM), op-amp/comparator output (VOUT), op-amp/comparator reference voltage (VSET), and internal die temperature. The I2C bus is compatible with 1.8V and 3.3V logic, allowing modern microcontrollers to interface to it.

The MAX9611 features a noninverting input-to-output configuration while the MAX9612 features an inverting input-to-output configuration.

The MAX9611/MAX9612 operate with a 2.7V to 5.5V supply voltage range, are fully specified over the -40°C to +125°C automotive temperature range, and are available in a 3mm x 5mm, 10-pin µMAX® package.

Applications

* Base-Station Feeder Cable Bias-T * Base-Station PA Control * Battery-Operated Equipment * Hybrid Automotive Power Supplies * Server Backplanes * Telecom Cards

* 0V to +60V Input Common-Mode Voltage Range

* 2.7V to 5.5V Power-Supply Range, Compatible with 1.8V and 3.3V Logic

* 5µA Software Shutdown Current

* Integrated 12-Bit ADC

* 13µV Current-Sense ADC Resolution

* 500µV (max) Current-Sense ADC Input Offset Voltage

* 0.5% (max) Current-Sense ADC Gain Error

* I²C Bus with 16 Addresses

* Small, 3mm x 5mm 10-Pin µMAX Package

* -40°C to +125°C Operating Temperature Range