Precision, High Side Current Sense Amplifiers

The LT1787 is a complete micropower precision high side current sense amplifier. The LT1787 monitors bidirectional currents via the voltage across an external sense resistor. A current or voltage output indicates the direction and magnitude of the sense current. The LT1787 delivers greater than a 12-bit dynamic range with ultralow 40µV input offset voltage compared to a typical 250mV full-scale input voltage. A fixed gain of 8 is set by onboard precision resistors. Input signal filtering is easily implemented with a capacitor between the FIL– and FIL+ pins. The LT1787HV operates from 2.5V to 60V total supply voltage and the LT1787 operates from 2.5V to 36V total supply voltage. Both versions have a PSRR in excess of 120dB. The LT1787/LT1787HV draw only 60µA and are available in 8-lead SO and MSOP packages.

Applications

* Battery Monitoring

* Power Monitoring

* Portable Phones

* Cellular Phones

* Portable Test/Measurement Systems

* Battery-Operated Systems

* Input Offset Voltage: 75µV (Max)

* 60V Supply Operation (LT1787HV)

* 12-Bit Dynamic Range

* Operating Current: 60µA

* User-Selectable External Sense Resistor

* Bidirectional High Side Current Sensing

* Unidirectional or Bidirectional Output

* Input Noise Filtering

* Available in 8-Lead SO and MSOP Packages

* –40°C to 125°C Operating Temperature Range