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? 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. ![]() 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'. ![]()
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