powering two ESP8266 from one source

Hi- I've breadboarded out a working circuit that requires two ESP8266 modules. On the breadboard I'm using two NodeMCU, and am levearging a breadboard power supply in addition to the USB. When I make my PCB, however, I'm going to be using just the ESP8266-12e modules. I'd planned on supplying each one with 3.3v from its own AMS1117-3.3 v-reg (800ma output) both fed by a 2A 5v wall supply. I know to connect the negatives of all together, but should I/can I connect also the positive rails (so they're essentially in parallel)? This seems like it would distribute the current more evenly, but of the several articles I've read, one said that this wouldn't work. What do you think?

Putting 2 linear regulators in parallel is a bad idea. Can (or should) two voltage regulators be connected in a parallel configuration. - Electrical Engineering Stack Exchange

Connect the grounds, but each ESP should have its own regulator, in this case.

groundFungus:
Putting 2 linear regulators in parallel is a bad idea. Can (or should) two voltage regulators be connected in a parallel configuration. - Electrical Engineering Stack Exchange

Connect the grounds, but each ESP should have its own regulator, in this case.

Thanks! Thinking about this a bit further though, do you think independent regs are needed? Looking back over the specs, and it appears the ESP can draw 170ma at full load, so two going full tilt is still ~42% of maximum capacity of the AMS1117...granted, two would be best, but is it necessary?

I have read various numbers relating to the current required by an ESP. From your 170mA to over 800mA while transmitting. I have always used a LM1117 for my ESP projects, but only 1 at a time. If only one is transmitting at a time 1 regulator for both should work. If both are transmitting at once, that I don't know. I guess testing would tell.

groundFungus:
I have read various numbers relating to the current required by an ESP. From your 170mA to over 800mA while transmitting. I have always used a LM1117 for my ESP projects, but only 1 at a time. If only one is transmitting at a time 1 regulator for both should work. If both are transmitting at once, that I don't know. I guess testing would tell.

Yikes, 800! I think I'll stick with both- it's only pennies, and will be safer in the long run. Thanks much for the help tonight!

ESP modules draw a lot of peak current while transmitting.
You can smooth that out by adding a beefy cap (1000uF) on the 3.3volt supply rail.
That smooths current out to an average of about 80mA per module.
Then one regulator shouldn't have any problem supplying two modules.
Not sure if they (transmitters/receivers) like being close to each other though.
Leo..

The maximal current stated by the datasheet is 170mA. I tend to beleive it could be higher sometimes, but 800mA sounds a little high. Especially paired with the assumption that it would occur on both ESP at the same time.
I am running mutliple ESP8266 24/7 on HT7333 with 250mA current limit, only backed by a 47uF tantalum cap. They all work 100% stable. (If they would not, lights would switch out randomly).

Thanks guys- I'll keep this all in mind for the future, as I just finished etching my board with two 3.3 regs. There's as much distance between them as I could manage (about 3cm), but will see if that works!

"Point of load" power regulation is generally useful as the supply traces can be a lot thinner across the board,
since you don't have to worry about 50 or 100mV drop across a 5V wire thats going into the input of a 3.3V
regulator at its destination. That can save more board area than is taken up by the regulator, and in this
case you are isolating the two devices from each other well.

A continuous ground-plane is assumed of course to keep the return IR losses small.

With two WiFi devices good power separation is probably wise should they be talking at the same time
on different channels.