Current sense amp operates as high- or low-side monitor

Linear Technology Corp. has announced a precision current sense amplifier with an input common mode range that extends from -0.3V below V-, up to 44V above V-. The common mode range of the LT6105 is independent of the positive supply voltage, making it suitable for a wide range of applications. As a result, the LT6105 can operate as a high-side or a low-side current sense monitor.

The LT6105 can continuously monitor current during a load short or power supply failure, as well as continuously monitor a battery from full charge to depletion. The LT6105 can directly monitor the current on a negative supply voltage and because the inputs of LT6105 can withstand differential voltages up to ±44V, it is suitable for monitoring loads connected through a fuse or a MOSFET switch.

The LT6105 promises excellent precision with only 300?V of input offset voltage and only 0.5?V/°C of input offset drift. Any gain between 1 to 100V/V can be designed with external resistors and gain error is limited to less than 1 percent maximum. The LT6105 operates with an independent supply voltage of 2.85V to 36V and draws only 150?A. When powered down, the sense pins are biased off, which prevents any loading of the sense resistor, irrespective of the sense voltage.

"The LT6105 is one of the most flexible current sense devices in the market today," said Mike Kultgen, design manager for Linear Technology. "It's a complete, precision current sense amplifier with a lot of features in a small package."

The LT6105 is in full production, with prices starting at 99 cents each in 1,000-piece quantities.