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Oldcodger · 11th Jul 2018, 10:38 pm

not sure if this is right place, as it could be circuits, or Modern or here.
I know that the "car " word is disliked, but it's where the kit is used, so it features and is very relevant.
Dashcam uses a USB supply derived from 12v supply to drive it. In normal use this is from a cigarette lighter plug to a USB socket.
From what I've read ( USB voltages etc are much of a mystery to me) , voltage is 5v, at varying current depending on units supplied ( for usb2 it's 100mA per unit) , and I'm getting sick of connection and fuse failure problems. And tthere's fact that my 12v socket is on permanantly. So simplest solution to me would be to use a 7805 from a switched supply. I've got stacks of 2A 7805, so anyone see any problems of the old 7805 circuit ,with something 330nF in and 100nF out ,or would it also need something like a 10-22uF on the output.

11th Jul 2018, 10:38 pm	#1
Oldcodger Nonode Join Date: Oct 2014 Location: West Midlands, UK. Posts: 2,181	12V to USB convertor. not sure if this is right place, as it could be circuits, or Modern or here. I know that the "car " word is disliked, but it's where the kit is used, so it features and is very relevant. Dashcam uses a USB supply derived from 12v supply to drive it. In normal use this is from a cigarette lighter plug to a USB socket. From what I've read ( USB voltages etc are much of a mystery to me) , voltage is 5v, at varying current depending on units supplied ( for usb2 it's 100mA per unit) , and I'm getting sick of connection and fuse failure problems. And tthere's fact that my 12v socket is on permanantly. So simplest solution to me would be to use a 7805 from a switched supply. I've got stacks of 2A 7805, so anyone see any problems of the old 7805 circuit ,with something 330nF in and 100nF out ,or would it also need something like a 10-22uF on the output.