In the following circuit it says: “This hysteresis effect can be eliminated however, using the circuit from a detailed application note from Littelfuse shown in Fig. 6.4.4. Here the capacitor C1 is fully discharged every time VS passes through zero. If the charge on the top plate of C1 is positive and point X is at zero volts, C1 will discharge to 0V via D3 and R4. If the charge on C1 is negative when X = 0V, C1 will be discharged via D1 and R3. When point X is either positive or negative C1 cannot be charged via D1 or D3 as the voltages at the bottom of R3 and R4 will be held within about +/-0.6V of zero due to the forward conducting voltage of either D2 (during the positive half cycle) or D4 (during the negative half cycle). C1 is therefore always charged via R1 and R2.”
- Where does C1 discharge to via D3/R4 and D1/R3? Does it discharge into the load?
- Why can’t the capacitor be charged through D1/D3 when X is either positive or negative if to me it looks like they’re connected similar to a bridge rectifier to the cap? Does the voltage just go back to Vs?
- Do the diodes convert ac to dc at the capacitor?
I’m sure I’m missing something simple here