The Linear Technology LT6109 is a complete high side current sense device. The LT6109 incorporates a precision current sense amplifier, an integrated voltage reference and two comparators. Two versions of the LT6109 are available. The LT6109-1 has the comparators connected in opposing polarity and the LT6109-2 has the comparators connected in the same polarity. In addition, the current sense amplifier and comparator inputs and outputs are directly accessible. External resistors configure the amplifier gain and comparator trip points. The open-drain comparator outputs allows for easy interface to other system components.
The overall propagation delay of the LT6109 is typically only 1.4 μs, allowing for quick reaction to overcurrent and undercurrent conditions. The 1 MHz bandwidth allows the LT6109 to detect errors in critical applications such as motor control. The high threshold accuracy of the comparators, combined with the ability to latch both comparators, ensures the LT6109 can capture high-speed events.