The PM-45 is a low-cost 4½-digit panel meter that uses an autozeroing dual-slope A/D converter to measure single-ended DC inputs from ±199.99 mV to ±1200 V, with a maximum resolution of 10 µV over ±19999 counts. It supports multiple operating modes, including ratiometric measurements, leading zero blanking, polarity reversal, and autoranging with overrange/underrange outputs. The display and logic circuits operate independently, allowing dimming, blanking, or “press-to-read” functionality without affecting measurement performance, and enabling instantaneous readings with no settling time.