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Topic: quick question, would this work? (Read 468 times) previous topic - next topic

andrewcat12



im trying to make my circuit more compact so i dont wanna use one of those bulky 5v to 3v3 adapters

BJHenry

No. Your Nano has a 3.3V output, try using that to power the NRF24L01. I've done just that (using Nanos with a CH340). Robotdyn also make a Nano with a more powerful 3.3V regulator that might be able to power the NRF24L01 a bit better.

MarkT

Power inputs to devices must be regulated power, any kind of resistive dropping will not
give a stable voltage and everything will misbehave.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

andrewcat12

No. Your Nano has a 3.3V output, try using that to power the NRF24L01. I've done just that (using Nanos with a CH340). Robotdyn also make a Nano with a more powerful 3.3V regulator that might be able to power the NRF24L01 a bit better.
ill try but i heard the 3v3 output didnt have enough current to supply the nrf24?

DrAzzy

ill try but i heard the 3v3 output didnt have enough current to supply the nrf24?
That may well be an issue.

You *cannot* use a resistor, as the current drawn by the NRF24 varies from near zero to... quite a bit more... depending on what it's doing. A resistor that provided 3.3v at peak current would leave almost 5v on the NRF24 when it wasn't drawing much current.

You must use a regulator - a 1117-series regulator in TO-220, with ceramic caps soldered right onto the leads, is probably the most compact solution.
ATtiny core for 841+1634+828 and x313/x4/x5/x61/x7/x8 series Board Manager:
http://drazzy.com/package_drazzy.com_index.json
ATtiny breakouts (some assembled), mosfets and awesome prototyping board in my store http://tindie.com/stores/DrAzzy

Wawa

A Nano gets it's 3.3volt from the USB<>serial chip,
The Nano clone I have (CH340 chip) can provide 30mA without collapsing.
It seems that the nRF24 is happy with 15mA.
Leo..

andrewcat12

That may well be an issue.

You *cannot* use a resistor, as the current drawn by the NRF24 varies from near zero to... quite a bit more... depending on what it's doing. A resistor that provided 3.3v at peak current would leave almost 5v on the NRF24 when it wasn't drawing much current.

You must use a regulator - a 1117-series regulator in TO-220, with ceramic caps soldered right onto the leads, is probably the most compact solution.
i think this is what i prefer out of all the solutions, ill research into this, thanks

BJHenry

ill try but i heard the 3v3 output didnt have enough current to supply the nrf24?
It is definitely worth a try. I've heard some people that have trouble with it, but as I said before it works for me.

PaulRB

I've heard of people having trouble with esp-01 WiFi modules powered through Nano's 3.3V. And no wonder, it's much more power hungry than nrf24. But the two look very similar to a beginner.

polymorph

You realize... everyone here has a "quick question", and wants to know "if it will work".
Steve Greenfield AE7HD
Drawing Schematics: tinyurl.com/23mo9pf - tinyurl.com/o97ysyx - https://tinyurl.com/Technote8
Multitasking: forum.arduino.cc/index.php?topic=223286.0
gammon.com.au/blink - gammon.com.au/serial - gammon.com.au/interrupts

andrewcat12

You realize... everyone here has a "quick question", and wants to know "if it will work".
think thats what forums are for

Wawa

I think the 3.3volt pin just lacks the buffer caps to power a transmitter that uses high current pulses.

I frequently power an ESP8266 module (80mA) from an Uno clone (150mA) to flash, but you DO need a (>=470uF) buffercap on that power line. Because the ESP draws ~400mA during the short transmit pulses.
Leo..

DrAzzy

think thats what forums are for
What hes saying is you should use a topic title that better describes the issue you're having in the future - that way people who know the answer can more easily find you
ATtiny core for 841+1634+828 and x313/x4/x5/x61/x7/x8 series Board Manager:
http://drazzy.com/package_drazzy.com_index.json
ATtiny breakouts (some assembled), mosfets and awesome prototyping board in my store http://tindie.com/stores/DrAzzy

MarkT

What hes saying is you should use a topic title that better describes the issue you're having in the future - that way people who know the answer can more easily find you
And others with the same problem can find the answer too...
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

polymorph

#14
Sep 23, 2018, 09:50 pm Last Edit: Sep 23, 2018, 09:52 pm by polymorph
Yes, that is what I mean. Imagine everyone titled their questions the same way:

Help me, I need help

Help me with this

I am at a loss, please help me

Quick question, will this work

How does this work

Help me make this work

There is a sticky post at the top of every section of the forum:
How to use this forum - please read.
Steve Greenfield AE7HD
Drawing Schematics: tinyurl.com/23mo9pf - tinyurl.com/o97ysyx - https://tinyurl.com/Technote8
Multitasking: forum.arduino.cc/index.php?topic=223286.0
gammon.com.au/blink - gammon.com.au/serial - gammon.com.au/interrupts

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