Hc05 current draw

hello, as i didn't saw a topic with this, i just wanted to ask why does the nrf24l01need a capacitor at the input as it draw only 10ma when working and the hc05 Bluetooth module as it draws 35ma doesn't require and runs pretty well ? i used a 47uF 25/16v cap combined with a ceramic 104 one at the nrf input also at the 3.3 and 5v regulators i have a ceramic one and bigger 220/~400 uf. without the ones at the nrf input it won't receive the signals from the tx unit or it will receive less than send. what could go wrong if i want to make sure these modules would work, if i add extra electrolytic /ceramic caps at the vcc input or bigger ones at vin input at each stage of voltage before regulating at different values?

It's because the transmission protocol in use transmits in very short bursts - the peak current during a TX interval is much greater than the average 10mA that you measured.

and would extra capacitors hurt in any way ?

No, except there is some risk of errors or damage while soldering, as the PCB was not really designed to accommodate those components.

Can i use a hc 05 module close to a nrf, both as receivers on the same pcb, i don t have quite much space so that i would have to fit them toghether, would they intefere and the orientations matter ?

But a 0.1µF capacitor is not going to assist.

The 220µF hidden underneath, yes. :sunglasses:

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