- on Microcontrollers
- Published in issue 7/2001 on page 0
LM 3822/24 Current Meter
ICs for measuring currents usually employ external sense resistors with values of a few tens of milliohms. Not only are such resistors difficult to obtain, the circuit board layout can have a disturbing effect on the accuracy of the measurement. This problem is eliminated by the LM3822 and LM3824 ICs from National Semiconductor (www.national.com), which have built-in sense resistors with a value of only 3 mW. A delta-sigma modulator converts the measured value into a digital value.