Is the following regulator valid, safe and efficient?
The transformer is a dual 7V output toroidal. So B1 is supposed to rectify out 14v and B2 taps the "center" to produce 7V.
INAE and I've never used dual bridges in a tapped arrangement like this so I thought I should ask before playing around with mains like this.
The following is the circuit corrected as discussed but without the regulators:
This is supposed to model the Amgis L01-6310 14V/7V transformer to see what sort of voltages might be supplied to the 12V/5V regulators (because I should have used a 12V/6V part since Vpeak of 14V is *1.414 = 19.8V. Secondaries have 7 ohms series resistance per datasheet. I have never modeled a transformer in LTSpice before but I reasoned the turns ratio is 120 / 14 = 8.57 squared = 73.5 but this seemed to be off by a factor of 2 so I figured the primary is wired in parallel for 120V mains so I doubled the ratio to 147 / 1.
Green is the 14V tap. Blue is the 7V tap. Red and light blue shows the load on the outputs.
So it seems I get 16V and 7.2V which isn't too bad. If it comes out to 16V thats only a 4V drop. But I don't think the 12V load will be loaded much. If I only load it with ~25 mA, I get 18V which is 6V * 0.025 = 150 mW.
INAE so this could all be wildly wrong. IIWAE it would probably still be wrong.