It still plays when I lower the voltage, all the way down to 1.8 V but then it's barely audible - below 3 V is not gonna cut it, I'm afraid). (The device/load is a gag-birthday card which plays music at a rather annoying volume it comes with 3 LR1130 batteries, 3 x 1.2 V = 3.6 V and using my bench supply I measured it using about 100 ~ 200 mA - I just want to control when it plays. My main question is: What can I do to get close(r) to the desired 3.6 V without using a ton of components? Add a dropper diode or two? Second: will this work at all? Does my reasoning make any sense at all? Using the 3.3 V is going to leave 2.7 V for the switched load, which is too low.This should drop around 0.6 V, leaving 5 V - 0.6 V = 4.4 V? This is a bit on the high side I'm afraid. I was planning on using a 2N2222 (but I have others) as my 'switch'.I need a 4k7 resistor to limit the current from the datapin (D4).Since a Wemos D1 pin can only handle about ~12 mA I need to use a transistor to switch the required 0.1~0.2 A. 2N2222A Small Signal Switching Transistor NPN Silicon Features MILPRF19500/255 Qualified Available as JAN, JANTX, and JANTXV MAXIMUM RATINGS (TA 25C unless otherwise noted) THERMAL CHARACTERISTICS Stresses exceeding those listed in the Maximum Ratings table may damage thedevice. All is powered by an 18650 shield that outputs both 5 V and 3.3 V. I want to be able to toggle the power to this device with a Wemos D1 mini (sadly, represented below as an Arduino since I can't find a Wemos in ). In the below schematic it's represented as a speaker. that draws about 0.1~0.2 A and requires 3.6 V.
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