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Pulse charging to constant flow Answered

So i had to replace the chargercable on our babycall and used a female usb port. The adapter uses 6 volts to charge the device but if i wanted to use a 5v portable charger, how can i make the current flow instead of pulsating? Capacitor? And what value?

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1
Downunder35m
Downunder35m

1 year ago

Sorry, but I fail to follow here.
If you need 6V to charge it then you can't charge it with just 5.

0
josvol81
josvol81

Reply 1 year ago

Thats Correct, i was’nt thinking. I actually thought i could charge it but it would take longer time, but it didnt work.

1
Jack A Lopez
Jack A Lopez

1 year ago

I am guessing your question about "flow instead of pulsating" [current] is the same topic Wikipedia calls "Ripple_(electrical)"

https://en.wikipedia.org/wiki/Ripple_(electrical)#...

The formula for choosing a filter capacitor, to reduce voltage ripple, is:

Vpp = I/(2*f*C)

where Vpp is the peak-to-peak voltage ripple (in V), I is load current (in A), f is frequency (in Hz or s^-1) of AC before it is rectified ( 2*f is frequency output from the rectifier), and C is the size of the capacitor (in F).

The section with that formula, is the one titled, "As a function of load resistance"

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josvol81
josvol81

Reply 1 year ago

Thank you :) i will look into this :)

1
Orngrimm
Orngrimm

1 year ago

Not exactly sure what the question is here... Pulsating? Is your 6V pulsating? If so, how and why?

If you want to boost 5V USB to 6V, you need a DC/DC-Booster like https://www.aliexpress.com/item/4000498014482.html
Connect it up to USB, Measure the voltage and adjust the pot for your 6V Output. Then connect the load which wants 6V.

0
josvol81
josvol81

Reply 1 year ago

Yeah i guess i need a DC booster. Tried to charge the babycall with a powerbank and the result is that the charge indicator light started pulsating, thats why i thought it was the current flow that was pulsating, but when i think about it its obvious that i need DC booster. Thank you :)