Here's what I built on the test bench. It seems most of the current gets shunted to GND and the cap in the device uses very little current to be kept at the provided voltage. I have a pair of DVMs - one measuring the voltage across the cap, and one measuring the current out of the pair of AAAs. I haven't tried the wall wart yet. In this configuration the meters are very unstable when the device's mains power is off. The voltage fluctuates between 1.49V and 0.9V, and current from the AAAs varies from 0 to a couple mA, but using digital meters the readings don't lock, they keep changing for the current. If that is OK, I can try the wall wart next.
I had forgotten that back in 2011 I had purchased a license for TINA 9 circuit simulator. Remembering that today, I drew up simulations of this project circuit. I have C1 just drawn by itself, but in the real environment it is part of the circuit inside the remote controlled switch.
I have attached copies of the circuit in action, both when C1 is kept alive by the 3.7V wall wart, and when it is in use while the remote controlled switch is live on mains power.
Note the tiny nA current increase back into the wall wart when the 5.5V power (of the remote controlled switch's circuit) is turned on. I presume such a small current is safely negligible for my application, and/or a product of using the simulator vs. real world conditions? I also can't input the actual diode I am using because TINA's database doesn't have a 1N5394. I tried some different listings in TINA and did see changes in the nano-amp current in both modes of operation. So I am not sure what it should actually read in the simulator using that diode. But on the bench it reads very low as well, fluctuating almost constantly in the DVM.
I had forgotten that back in 2011 I had purchased a license for TINA 9 circuit simulator. Remembering that today, I drew up simulations of this project circuit. I have C1 just drawn by itself, but in the real environment it is part of the circuit inside the remote controlled switch.
I have attached copies of the circuit in action, both when C1 is kept alive by the 3.7V wall wart, and when it is in use while the remote controlled switch is live on mains power.
Note the tiny nA current increase back into the wall wart when the 5.5V power (of the remote controlled switch's circuit) is turned on. I presume such a small current is safely negligible for my application, and/or a product of using the simulator vs. real world conditions? I also can't input the actual diode I am using because TINA's database doesn't have a 1N5394. I tried some different listings in TINA and did see changes in the nano-amp current in both modes of operation. So I am not sure what it should actually read in the simulator using that diode. But on the bench it reads very low as well, fluctuating almost constantly in the DVM.
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