I can be driving or at idle and all the gauges and radio blink out or flicker and then come back on, the car will still be running or driving or in idle but i'll have to reprogram the radio again....the tach goes to zero too

recently yesterday i was in idle in a drive thru and everything flickers and blinked out and the car went dead. I was able to start it back up, but i was curious as to what could be causing this....