Hi guys!
I need a 5.5v and 3.3v supply to power a circuit (which got two supply). So I decided to use
LM317 variable voltage regulator. My idea was a 9v battery and step down to 5.5v and a 3.3v. I looked up the datasheet and patched up the circuit as followed:
http://www.national.com/mpf/LM/LM317.html#Overview
So I used two of LM317 to get a 5.5v and 3.3v output. I managed to test it out via a multi-meter after adjusting the variable potentiometer. It went correctly. A 5.5v and 3.3v output each.
The weird thing was when I used the output to power my circuit, the output voltage dropped. From the multi-meter it reads 1.9v(supposed to be 5.5v) and 2.7v(for a 3.3v output). The voltages was simply too low to get my circuit working.
I really don't understand why.
Wasn't it supposed to be 5.5v and 3.3v powering my circuit? When connected up to the power, why it became 1.9v and 2.7v???
Uhhh. Anyone??
I need a 5.5v and 3.3v supply to power a circuit (which got two supply). So I decided to use
LM317 variable voltage regulator. My idea was a 9v battery and step down to 5.5v and a 3.3v. I looked up the datasheet and patched up the circuit as followed:
http://www.national.com/mpf/LM/LM317.html#Overview
So I used two of LM317 to get a 5.5v and 3.3v output. I managed to test it out via a multi-meter after adjusting the variable potentiometer. It went correctly. A 5.5v and 3.3v output each.
The weird thing was when I used the output to power my circuit, the output voltage dropped. From the multi-meter it reads 1.9v(supposed to be 5.5v) and 2.7v(for a 3.3v output). The voltages was simply too low to get my circuit working.
I really don't understand why.
Wasn't it supposed to be 5.5v and 3.3v powering my circuit? When connected up to the power, why it became 1.9v and 2.7v???
Uhhh. Anyone??