SNOSB14E August 2009 – July 2024 LPV521
PRODUCTION DATA
Small signals from transducers in remote and distributed sensing applications commonly suffer strong 60Hz interference from ac power lines. The circuit of Figure 7-3 notches out the 60Hz and provides a gain AV = 2 for the sensor signal represented by a 1kHz sine wave. Similar stages can be cascaded to remove 2nd and 3rd harmonics of 60Hz. Thanks to the nA power consumption of the LPV521, even five such circuits can run for 9.5 years from a small CR2032 lithium cell. These batteries have a nominal voltage of 3V and an end of life voltage of 2V. With an operating voltage from 1.6V to 5.5V, the LPV521 can function over this voltage range.