Voltage Distribution Question

[CGlass08]

Hello! New to the forums here!

I am new to electronics design and am trying to design a thermostat. I am planning on using the 24V AC coming out of the wall to power everything in my thermostat (microcontroller, sensor, 802.11b chip) and they all require 3V input. I have searched and searched and cannot find anyone else doing this? I am sure it is possible but just have no idea where to start with my circuit design. I appreciate any help that anyone can provide me! Thank you!

 

[CGlass08]

bump. Do I need a voltage regulator like the one here?

3.3V switching voltage regulator - 7803 replacements

Or possibly need to implement a circuit like the one shown here and just adjust resistor values in order to obtain 3.3 V?

Circuit Solutions, Non-Isolated Off-Line AC to DC Power Supply by David Johnson P.E.

 

[BeeBop]

Hello! New to the forums here!

I am new to electronics design and am trying to design a thermostat. I am planning on using the 24V AC coming out of the wall to power everything in my thermostat (microcontroller, sensor, 802.11b chip) and they all require 3V input. I have searched and searched and cannot find anyone else doing this? I am sure it is possible but just have no idea where to start with my circuit design. I appreciate any help that anyone can provide me! Thank you!

What you need to do is build or buy a DC power supply to convert the 24V AC to 3V DC.
At 24V input, you are going to dissipate (and waste,) a lot of power to get 3V out with a linear power supply. A switcher would do it for you with less waste, or you could use a small transformer to drop the 24VAC to 5 or 6VDC and use a linear regulator.

This looks like a good place to send you to introduce you:
Power Supplies