as a matter of hobby, I am developing a digital voltmeter. to read the ac voltage, I thought of using a V transformer so that the Voltage is step down for our electronic circuitry to measure. To my amazement, I found the normal commercial products (digital voltmeter) dont use transformers but how in the world do these devices interface AC Voltage (110Vrms/220Vrms) to electronic circuitry without burning them? And yes, I tried to get rid of transformers by using voltage divider network and opamp at the rear end but the whole affair ended in a smoke literally, the opamp got blown off.any idea? AC opamps? or whatever?