How to design this esp01 dht22 board for powering both components

Thread Starter

quique123

Joined May 15, 2015
388
So I've gone through some ideas on designing this simple sensor box. It's a 5Vdc power plug that feeds into an lm1117 which feeds the esp01 and dht22.

The esp01 takes 3.3V but the dht22 5v. I figured I can tap the 5v before the lm1117 and the 3.3v after. Does that sound right?

80E5F1CA-BFC4-4061-B070-0C1BEBF0AED1.jpeg
 

ericgibbs

Joined Jan 29, 2010
9,114
Hi,
The problem with two voltage levels is that level shifting is required between the 3.3v and 5v logic levels.
I would use 3.3v
E
Don't forget the pull resistor on the DHT data line.
 

Thread Starter

quique123

Joined May 15, 2015
388
OK another question. I'm powering both units from the 3.3V coming out of the lm1117. Can I take the 3.3v line to the dht22 and after that take it to the esp01s Vcc/Ch_Pd? The solid red line shown.

Or should I give power from 3.3V to dht22 Vcc and also from 3.3V to the esp01s Vcc/Ch_Pd as shown by the dashed line?

235D5842-E25A-49C3-BC26-58C4CC123ED4.jpeg
 

Thread Starter

quique123

Joined May 15, 2015
388
OK one last thing. For the power connector, this is the one I have. I can easily solder the Vcc pin on the power connector laying it flat on the board but this would make the GND terminal orientation 90 degrees wrt the board. What would be the best way to make its connection down to the board?

1EC32414-F8F8-4735-BDAD-43D95DFB5ECB.jpeg
 

ericgibbs

Joined Jan 29, 2010
9,114
hi,
To give added mechanical strength to the connector mounting, insert a 40 thou solder pin thru a hole that aligns with the right angled tag of the connector, as shown in your image, solder the connector to the pin and PCB track.
The PCB hole pitch is 0.1inch but the connector appears to have a different pitch, so use thick solid wire to connect the other pins of the connector the required PCB pad.
Do you follow that OK.?
E
 
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