20V to +75V Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers

The MAX9918/MAX9919/MAX9920 are single-supply, high-accuracy current-sense amplifiers with a high input common-mode range that extends from -20V to +75V. These amplifiers are well suited for current monitoring of inductive loads such as motors and solenoids, where common-mode voltages can become negative due to inductive kickback, reverse-battery conditions, or transient events.

The MAX9918/MAX9920 feature adjustable gain set by an external resistive-divider network. The MAX9919 features fixed gains of 45V/V (MAX9919F) and 90V/V (MAX9919N). The MAX9918/MAX9919/MAX9920 operate as unidirectional amplifiers when VREFIN = GND and as bidirectional amplifiers when VREFIN = VCC/2. The MAX9920 attenuates the input signal by a factor of 4 at the input level-shifting stage allowing the device to sense voltages up to 200mV (unidirectional operation) or ±100mV (bidirectional operation).

The MAX9918/MAX9919/MAX9920 operate with a single 5V supply voltage, are fully specified over the -40°C to +125°C automotive temperature range, and are available in an 8-pin SOIC package.

Applications

* Automotive * Current Monitoring of Inductive Loads * H-Bridge Motor Current Sensing * High- and Low-Side Precision Current Sensing * Precision High-Voltage Current Monitoring * Solenoid Current Sensing * Super-Capacitor Charge/Discharge Monitoring

* Reduce Protective Clamping for High Inductive Kickback Voltage

* -20V to +75V Input Common-Mode Voltage Range

* Supports Wide Range of Precision AC and DC Current Sensing Applications

* Uni- or Bidirectional Current Sensing

* 0.6% (max) Gain Accuracy Error

* 400µV (max) Input Offset Voltage

* 120kHz, -3dB Bandwidth (MAX9919N)

* Reference Input for Bidirectional OUT

* Rail-to-Rail Output

* Saves Board Space

* 8-Pin SOIC Package

* Single-Supply Operation (4.5V to 5.5V)

* AEC-Q100 Qualified (MAX9918ASA/V+, MAX9919FASA/V+, MAX9919NASA/V+, MAX9920ASA/V+ Only)