Hello guys
So after a lot of search in market I am not able to find lm1117 3.3v regulator in the market for my esp8266. So what I tried here is voltage divider by using 2.2k ohm and 1k ohm resistor but the weird issue I am facing here is that when I connect ch_pd to 3.3v my esp8266 goes
off. What could be the problem here?
Thank in advance
It's not one of these?
No way will that work. The ESP8266 draws a a couple hundred mA peak. You can only use a voltage divider when you're not pulling any current. It's only for reference voltages (per ohm's law, what would happen if you draw current from the middle? The key assumption of a voltage divider is no longer valid)
You need a regulator. You could use any of these through-hole regulators:
Sortable/filterable list of appropriate 3.3v regulators in the Digikey catalog
DrAzzy:
No way will that work. The ESP8266 draws a a couple hundred mA peak. You can only use a voltage divider when you're not pulling any current. It's only for reference voltages (per ohm's law, what would happen if you draw current from the middle? The key assumption of a voltage divider is no longer valid)You need a regulator. You could use any of these through-hole regulators:
Sortable/filterable list of appropriate 3.3v regulators in the Digikey catalog
Thanks for the reply
Look like the only way I got here is to use voltage regulator but I was not able to find one. What could be the alternative?
There have been post in the forum where people have apparently successfully powered the ESP8266 directly from the arduino 3.3v. I've got a ESP8266 somewhere which I may wire up and see what happens.
saifkazi:
Thanks for the replyLook like the only way I got here is to use voltage regulator but I was not able to find one. What could be the alternative?
Which territory are you? Someone will know your best electronics stockist given that detail!
MarkT:
Which territory are you? Someone will know your best electronics stockist given that detail!
I live in india , mumbai Actually i did find ams1117t voltage regulator but thats a surface mount device how am i gonna hook up to breadboard or copper pcb ? what i was looking for is TO-220package
saifkazi:
Actually i did find ams1117t voltage regulator but that's a surface mount device how am I gonna hook up to breadboard or copper PCB?
Well, you need a soldering iron. If you are going to work with electronics, you must be proficient in soldering - there really is no alternative.
Whilst SOIC and such ICs with many pins are difficult to work with, this regulator has only three pins, and the middle one is the same as the tab on the other side so you only need to solder pieces of wire to the tab and the two outer pins, That should not be really difficult.
Generally, for prototyping, one uses the pieces of wire cut off resistors when you solder them (the old-fashioned ones with wires, not the SMD ones) into a PCB. If you solder such pieces to your SMD regulator, you can use it with a breadboard. Soldering to a PCB should not be too much more difficult.
Paul__B:
Well, you need a soldering iron. If you are going to work with electronics, you must be proficient in soldering - there really is no alternative.Whilst SOIC and such ICs with many pins are difficult to work with, this regulator has only three pins, and the middle one is the same as the tab on the other side so you only need to solder pieces of wire to the tab and the two outer pins, That should not be really difficult.
Generally, for prototyping, one uses the pieces of wire cut off resistors when you solder them (the old-fashioned ones with wires, not the SMD ones) into a PCB. If you solder such pieces to your SMD regulator, you can use it with a breadboard. Soldering to a PCB should not be too much more difficult.
Will 10uf capacitor will do good with this ?
saifkazi:
Will 10uf capacitor do good with this ?
I fail to see the relation between the quoted text and your last question.
You can use 3 diodes and a 5 volt cellphone charger use diodes that are rated for 500 mA but you need to test the drop of the diodes most will work but some drop the power to low. If to low use just two but you have to test to be sure I got a bag of 500 and some drop .6 volts each which gets me 3.6 on my laptop using the usb for power and some drop .7 volts and the esp didn't like it that low so test there drop start with 3 and read the voltage if its above 3.3 your good
5 volt +------>|------->|--------- should be 3.4 but test you may need 3 of them.
And AL shows on there data sheet how to do this also to make a test board for the esp8266 using the ch340g usb to serial chip and usb for power.
These thing are kind of funny I have 6 and 4 are esp8266-12 and 2 are the esp8266-12Q And they can use power over 250mA but most times it's around 150 to 200 it depends on what your doing with it sending data draws more but it's all in how long it takes to send.
The ESP8266 will operate from two (alkaline) dry cells, which is less than 3V. If you use diodes to drop the voltage, you really need a fairly large electrolytic on the 3(.3) V rail for stability. 100 µF would be minimum.