9v to 3.3v converter using AMS1117-3.3 SOLVED

hello I'm trying to make a wireless audio system i did it on a breadboard got everything wired up and i would like to take it on the road with me. i have a AMS1117-3.3v converter powering up up a attiny84 with a nrf24l01 with a lm386 audio amp Problem is not sure what i would need with the AMS1117-3.3v to keep it safe i know the AMS1117-3.3v is used on the uno boards they have caps on them on the input to protect them. not sure what i would need for the 9v one or how long into the battery dies out.

This regulator has low current capacity, how much current does your circuit use?

Not sure what the nrf module takes but it's most likely 200 to 400 Milla amps with the audio amp and attiny84 and 4 leds on it.

josephchrzempiec:
Not sure what the nrf module takes but it's most likely 200 to 400 Milla amps with the audio amp and attiny84 and 4 leds on it.

Cheking the Arduino UNO specs:

"3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA."

You'll have to use another model I guess.

josephchrzempiec:
hello I'm trying to make a wireless audio system i did it on a breadboard got everything wired up and i would like to take it on the road with me. i have a AMS1117-3.3v converter powering up up a attiny84 with a nrf24l01 with a lm386 audio amp Problem is not sure what i would need with the AMS1117-3.3v to keep it safe i know the AMS1117-3.3v is used on the uno boards they have caps on them on the input to protect them. not sure what i would need for the 9v one or how long into the battery dies out.

The 1117 is a linear regulator, not a converter. It will dissipate a lot of heat if
you have it handle a lot of current with the input at 9V and output at 3.3V since
nearly 6V are across it.

With that voltage ratio a DC-DC converter would be a better choice, such as
these: http://uk.farnell.com/xp-power/tr05s3v3/dc-dc-converter-0-5a-3-3v-sip/dp/2319829

NEAT PART - that's a DC-DC buck converter wrapped up into a 3 pin package, for sale at... $4-5 each in small quantities?!
That is really handy where space is tight.

On the other hand, you can get adjustable dc-dc buck converter boards for really really cheap on ebay. Search for "buck converter", and you'll get a deluge of results, mostly the $1-1.50 LM2596 based ones.

Finally, 9v batteries suck - if you're using much power, you'll be disappointed with the battery life. Use either arrays of AA's or Li-ions. (I like 18650 rechargables - just bear in mind that the mAh spec is wildly optimisitic on the cheap ones)

hello okay here is my problem i have a pro mini board with the 328p chip on it and it can only be power up with 5v that is how it's made i have a nrf24l01 module and it only takes 3.3v now the problem is i got a 9v source and need to power up that 3.3v because the pro mini don't have the 5v to 3.3 converter on it and the pro mini needs to go from 9v to 5v also.

If its just the nRF24L01 on 3.3V then 1117 3.3V regulator from the Pro Mini’s 5V rail will
be fine. A DC-DC converter from 9V to 5V makes sense to extend battery life. Small 9V
battery will struggle to source more that 100mA or so, BTW, so a DC-DC converter will
defnitely help.

hello no this pro min doesn't have a 5v to 3.3v converter on it that is the problem.

this pro min doesn't have a 5v to 3.3v converter on it that is the problem.

But Mark just said to use a 1117 from the 5v power rail, it has one of them doesn't it?


Rob

i have a 1117 to 3.3v converter chip I'm trying to use. plus i figure it out i didn't know whats the max input voltage that 1117 chip takes 4.8V so a 5v source will work then converts it to 3.3v which is okay that is what i needed. i think i solved it thank you