LT®6109 Current Sense Amplifier

By Analog Devices Inc 213

LT®6109 Current Sense Amplifier

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.

  • Current sense amplifier
    • Fast step response: 500 ns
    • Low offset voltage: 125 μV max
    • Low gain error: 0.2% max
  • Internal 400 mV precision reference
  • Wide supply range: 2.7 V to 60 V
  • Supply current: 550 μA
  • Internal latching comparators with reset
    • Fast response time: 500 ns
    • Total threshold error: ±1.25% max
    • Two comparator polarity options
  • Low shutdown current: 5 μA max
  • Specified for -40°C to 125°C temperature range
  • Available in 10-lead MSOP package