Features

• Current Sense Amplifier
  – Fast Step Response: 500ns
  – Low Offset Voltage: 125μV Maximum
  – Low Gain Error: 0.2% Maximum
• Internal 400mV Precision Reference
• Internal Latching Comparators with Reset
  – Fast Response Time: 500ns
  – Total Threshold Error: ±1.25% Maximum
  – Two Comparator Polarity Options
• Wide Supply Range: 2.7V to 60V
• Supply Current: 550μA
• Low Shutdown Current: 5μA Maximum
• Specified for –40°C to 125°C Temperature Range
• Available in 10-Lead MSOP Package

Typical Application

Description

The LT®6109 is a complete high side current sense device that 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. The amplifier gain and comparator trip points are configured by external resistors. The open-drain comparator outputs allows for easy interface to other system components.

The overall propagation delay of the LT6109 is typically only 1.4μs, allowing for quick reaction to overcurrent and undercurrent conditions. The 1MHz bandwidth allows the LT6109 to be used for error detection 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.

The LT6109 is fully specified for operation from –40°C to 125°C, making it suitable for industrial and automotive applications. The LT6109 is available in a small 10-lead MSOP.