DIY "keep-alive" for Power Bank

How to bypass the automatic shutdown of the Power Bank when connecting low-power devices such as LEDs, ICs, Arduino and other microcontrollers.

[@skipper7351]

What will happen if you replace R4 into a 10 ohm?

[@3iii]

The power consumption of this device will increase because R4 acts as a load.

[@skipper7351]

@@3iii that's exactly what i was looking for. thanks

[@skipper7351]

@@3iii Is there a way to influence the spacing between the pulses and the duration of the pulse. Or is it not possible to change these two time values

[@3iii]

I made many experiments with R1, R2 and C1 values. I chose the most optimal for my powerbanks considering power consumption and power off timeout. But of course you can modify them. NE555 datascheet offers these formulas: Time high = 0.693 * (R1+R2) * C1, Time low = 0.693 * R2 * C1

[@skipper7351]

@@3iii this means that the interval between the pulses is 0.693×4 270 000×0.000001 = 2.95911 seconds and the duration of the pulse is 0.693×270 000×0.000001 = 0.18711 seconds with a load of 0.2A . you change the distance with R1. duration is changed with R2 and you can change the load with R4