Abstract: An improved isolated analog sense circuit comprises a sensor for passively sensing voltages, a transformer, a capacitor, a clock signal generator, a switch, and a diode. The transformer has two windings, the first of which is coupled to the sensor with the transformer coupling the voltage to be sensed from the first winding to the second winding. The switch is coupled between the capacitor and the second winding, and is responsive to the clock signal generated by the clock signal generator. Operation of the switch causes the capacitor to charge up to a voltage representative of the sensed voltage. The diode is included in the sensor to prevent current flow in the first winding of the transformer when the switch is off.