·No External Sense Element Required
·PWM Output Indicates the Current Magnitude and Direction
·PWM Output can be Interfaced with Microprocessors
·Precision AE Current-Sense Technique
·Low Temperature Sensitivity
·Internal Filtering Rejects False Tripsl
·Internal Power-On-Reset(POR)
APPLICATIONS
·Battery Charge/Discharge Gauge
·Motion Control Diagnostics
·Power Supply Load Monitoring and Management
·Resettable Smart Fuse
KEY SPECIFICATIONS
· Ultra Low Insertion Loss(Typically 0.0049)
· 2V to 5.25V Supply Range
· ±2% Accuracy at Room Temperature(Includes Accuracy of the Internal Sense Element) (LM3812-1.0, LM3813-1.0)
· Low Quiescent Current In Shutdown Mode (Typically 2.5 μA)
· 50 msec Sampling Interval
DESCRIPTION
The LM3812/LM3813 Current Gauges provide easy to use precision current measurement with virtuallyzero insertion loss(typically 0.004Q). The LM3812 is used for high-side sensing and the LM3813 is used for low-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 indicatesthe 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 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.
(Picture: Pinout)
