Intelligent Digital Voltage Meter Design and Implement Based on AD7715

AD7715 is a high accuracy A/D converts chip made by American company Analog – Devices which involves a programmable gain amplifier, a programmable digital filter. It employs the Σ-Δ ADC technology to realize the 16-bits accurate measurement. The voltage meter uses 89C55 SCM as control, uses analog switch to conduct multi switch for measured voltage through signal conditioning, uses new 16-bit A/D convert to sample measured voltage being conditioned, uses 128 X 64 dot-matrix LCD as display screen to show the wave and Chinese words. This article mainly introduces the means of applying AD7715 chips to design accurate voltage meter.