GENERAL DESCRIPTION
The LM3812/LM3813 Current Gauges provide easy to use precision current measurement with virtually zero insertion loss (typically 0.004Ω). 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 LM3812 and LM3813 are factory-set in two different current options. The sense range is −1A to +1A or −7A to +7A. The sampling interval for these parts is 50ms. If faster sampling is desired, please refer to the data sheets for the part numbers LM3814 and LM3815. Key Specifications n Ultra low insertion loss (typically 0.004Ω) n 2V to 5.25V supply range n ± 2% accuracy at room temperature (includes accuracy of the internal sense element) (LM3812-1.0, LM3813-1.0) n Low quiescent current in shutdown mode (typically 2.5 µA) n 50 msec sampling interval FEATURES
n No external sense element required n PWM ou...
National Semiconductor
