Hi, I have a problem with powering esp8266-01 wifi module, it needs 3.3V and 170 mA, so I bought MB-102 power supply to meet the requirements, I soldiered 100 microFarad capacitor between GND and 3.3V pins to make voltage more stable, but it isn't working.
Led on the wifi module is on, but I can't load the code. For sure it is problem with powering, because when I'm changing power supply to ATX power supply, from the old computer, everything is working fine.
The "MB-102 power supply" is essentially as useless as the regulator on a standard UNO. Perhaps you had better tell us how you are powering that.
What voltage do you actually read on the 3.3 V line?
That said, if powered from 5 V, the "MB-102 power supply" should be sufficient to program the ESP-01, but not to have it connect anywhere on WiFi. A 1 mF (millifarad) capacitor might be better.
Ok, I will try with another capacitor. Here is the power supply that I'm using to power MB-102 module. I don't want to power esp module from 5V, because it can kill it.
Go get a phone charger, plug it into the "MB-102 power supply" via the USB connector (may need an adapter) and it might work.
But what voltages did you measure on the 3.3 V line?
michskib:
. . . it needs 3.3V and 170 mA, so I bought MB-102 power supply to meet the requirements
I've seen measurements of 300 mA peak current for ESP-01 during startup. These are fast transients when the radio turns on, but they will crash the processor if the power rail isn't capable of providing it.
I soldiered 100 microFarad capacitor between GND and 3.3V pins to make voltage more stable, but it isn't working.
I had better luck with low ESR/low inductance capacitors (e.g. tantalum) and ran into problems with aluminum electrolytics doing this sort of thing. One also wants to pay attention to minimizing the wire length between regulator and ESP. My ESP-01 setup has the regulator and tantalum capacitor essentially soldered across the pins of the ESP-01 socket on a perfboard.
Paul__B:
Go get a phone charger, plug it into the "MB-102 power supply" via the USB connector (may need an adapter) and it might work.But what voltages did you measure on the 3.3 V line?
Do you mean USB to DC adapter?
I measured 3.3V
MrMark:
I've seen measurements of 300 mA peak current for ESP-01 during startup. These are fast transients when the radio turns on, but they will crash the processor if the power rail isn't capable of providing it.
MB-102 should provide up to 700mA
I used 33 macroFarad tantalum capacitor and it still the same. I got you wrong, voltage on the line is around 3.2 to 3.25 on both ATX power supply and MB-102 module, but I read in esp data sheet that it should work properly with 3-3.3 V on the line so everything should be correct, but isn't.
Paul__B:
The "MB-102 power supply" is essentially as useless as the regulator on a standard UNO.
So what powering do you recommend?
michskib:
MB-102 should provide up to 700mA
For a couple of seconds, before it shuts down due to heating.
michskib:
So what powering do you recommend?
A regulator with adequate capacitors and a heatsink.
Actually, no, not that. A switchmode regulator module - a dollar or two on eBay.
michskib:
MrMark:
I've seen measurements of 300 mA peak current for ESP-01 during startup.MB-102 should provide up to 700mA
Yes, but the problem is not the absolute current draw, the problem is the transient and there the length of the wire back to the regulator and it's resultant inductance and resistance matter. The ESP-01 is designed as a module to be plugged into a circuit board with proper ground planes and power distribution and it's flaky at best when hanging on the end of a couple skinny jumper wires.
It's a bit late for this but using an ESP board with onboard voltage regulator (e.g. a NodeMCU board) virtually eliminates the sort of issues you're seeing. That's not to say the ESP-01 module doesn't work, but that it doesn't tolerate makeshift power rails well.
Thank you guys for your help, I ordered switchmode regulator module that was recommended by Paul__B. I am newbie to arduino and I didn't know that ESP-01 has such problems with powering, but you have to make mistakes when you are new to something. I think everything is clear now and the problem is solved.