The MAX9918ASA+ is a precision unidirectional/bidirectional current sense amplifier in 8 pin NSOIC package. This single supply, high accuracy current sense amplifier has high input common mode range that extends from -20V to +75V. It is 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 has adjustable gain set by an external resistive divider network. The device operates as unidirectional amplifier when VREFIN = GND and as bidirectional amplifier when VREFIN = VCC/2. It is used in high and low side precision current sensing, super capacitor charge/discharge monitoring and precision high voltage current monitoring applications.
Supply voltage range from 4.5V to 5.5V
Automotive temperature range from -40°C to 125°C
Small signal -3dB bandwidth of 75KHz (VSENSE = 50mV) and slew rate of 0.6V/μs
Supports wide range of precision AC and DC current sensing applications
Gain error of ±0.08% at TA = +25°C (VRS+ = VRS- =+14V)
Input offset voltage of ±0.14mV at TA = +25°C (VRS+ = VRS- = +14V, VREFIN = 0V)
Rail to rail output, reference input for bidirectional OUT
CMRR of 96dB (20V <= VCM <= +75V) & PSRR of 103dB (4.5V <= VCC <= 5.5V)
Input offset current of ±8μA and input bias current of ±175μA at TA = +25°C
(EN)
