General Description

The MAX49918 is a high-precision current-sense amplifier (CSA) with an I2C programmable gain option from 10V/V to 200V/V in 8 steps. The multiple programmable gain options offer maximum flexibility for the user to change gain on-the-fly.

The IC operating input common-mode range from -5V to +70V, with protections that extend down to -6V and up to +80V, thus providing protection against reverse-battery and high-voltage spikes.

The low input offset of ±1μV (typ) and low gain error of ±0.01 (typ) make this device best-suited for high-precision current measurements.

The IC operates from a supply voltage of +2.7V to +5.5V with a typical quiescent supply at 0.7mA. The device operates over the full -40°C to +125°C temperature range.

The IC features bidirectional current sensing and is offered in a 3mm x 3mm, 10-pin TDFN ackage.

Benefits and Features

• Programmable Gain Options through I2C from 10V/V to 200V/V (8 steps)

• ±1μV (typ) Input Offset Voltage for REF1 = REF2 = VDD/2

• ±5μV (typ) Input Offset Voltage for REF1 = VDD and REF2 = GND at Gain = 20V/V

• ±0.01 (typ) Gain Error

• -5V to +70V Input Voltage Range

• -6V to +80V Protective Immunity

• 70kHz, -3dB Bandwidth at Gain = 20V/V

• 145dB DC CMRR

• Rail-to-Rail Output

• 3mm x 3mm, TDFN-10 Package

• -40°C to +125°C Temperature Range

Applications

• Monitoring Distinct Current Levels

• Using the Same Current-Sense Resistors Across Multiple System Variants

• Requires a Non-Typical Gain Value Due to Sense Resistor Constraints

• H-Bridge Motor and Solenoid Current Sensing

• Battery Current Monitoring

• High- and Low-Side Precision Current Sensing