1. The problem statement, all variables and given/known data Design a rectifier with a zener diode that satisfies the following: Primary voltage = 120V @ 60Hz V_{DC} = 12V I_{R2} = 100 mA (R2 being the load) V_{r(R2)} <= .3V 2. Relevant equations C=I_{DC}/(2fV_{r}) I_{DC}=I_{R3} + I_{R1} 3. The attempt at a solution I tried calculating the capacitor, but how am I supposed to get I_{DC} if I dont have any other current?
Remember that a reversed Zener diode clamps the voltage, but must be above the zener current ([itex]i_{zk}[/itex]) in order to do so: http://www.electronics-tutorials.ws/diode/diode_7.html