LM3822  Product Folder

The LM3822 Current Gauge provides easy to use precision current measurement with virtually zero insertion loss (typically 0.003Ohm). The LM3822 is used for high-side sensing.

A Delta Sigma analog to digital converter is incorporated to precisely measure the current and to provide a current averaging function. Current is averaged over 50 msec time periods in order to provide immunity to current spikes. The ICs have a pulse-width modulated (PWM) output which indicates the current magnitude and direction. The shutdown pin can be used to inhibit false triggering during start-up, or to enter a low quiescent current mode.

The LM3822 is factory-set in two different current options. The sense range is -1.0A to +1.0A or -2.0A to +2.0A. The sampling interval for this part is 50ms. If faster sampling is desired, please refer to the data sheet for the part number LM3824.

• No external sense element required
• PWM output indicates the current magnitude and direction
• PWM output is easily interfaced with microprocessors and controllers
• Precision [Delta][Sigma] current-sense technique
• Low temperature sensitivity
• Internal filtering rejects false trips
• Internal Power-On-Reset (POR)
• DC Offset is less than 1 mA for 1A part

• Ultra low insertion loss (typically 0.003Ohm)
• 2V to 5.5V supply range
• ±2% accuracy at room temperature for the 1A device (includes accuracy of the internal sense element)
• Low quiescent current in shutdown mode (typically 1.8 µA)
• 50 msec sampling interval
• In MSOP-8 Package

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• Resettable smart fuse