Hi All,
I have a 28vDC supply and want a 5vDC 10mA + 3.3vDC 100mA deriving from it. I have used tried a few LDO regulators just wired up by hand to test the outputs and I have tried two configurations.
First configuration was with the 28vDC feeding both regulators, both regulators can handle 30v in, but for some reason the 3.3v regulator popped and and blew up the HC-O5 I had attached to it, this happened twice after approx 30-40 seconds!! I did it a second time because I thought it might have been a faulty regulator. When I did not have the HC-05 connected the output showed 3.3v without issue.
The second configuration has the 5v regulator output feeding the 3.3v regulator input, but in this configuration the 5v regulator got hot (didn't blow just got hot to the touch) .
So my questions if what is the best way to get 5vDC 10mA + 3.3vDC 100mA from 28vDC supply. both the 5v and 3.3v supply IC's
Thanks
Steve
P.S. I am thinking about using two Zener + resistors but am not sure this is best approach, also if any part of my email does not sense don't flame just ask me to clarify.
I have a 28vDC supply and want a 5vDC 10mA + 3.3vDC 100mA deriving from it. I have used tried a few LDO regulators just wired up by hand to test the outputs and I have tried two configurations.
First configuration was with the 28vDC feeding both regulators, both regulators can handle 30v in, but for some reason the 3.3v regulator popped and and blew up the HC-O5 I had attached to it, this happened twice after approx 30-40 seconds!! I did it a second time because I thought it might have been a faulty regulator. When I did not have the HC-05 connected the output showed 3.3v without issue.
The second configuration has the 5v regulator output feeding the 3.3v regulator input, but in this configuration the 5v regulator got hot (didn't blow just got hot to the touch) .
So my questions if what is the best way to get 5vDC 10mA + 3.3vDC 100mA from 28vDC supply. both the 5v and 3.3v supply IC's
Thanks
Steve
P.S. I am thinking about using two Zener + resistors but am not sure this is best approach, also if any part of my email does not sense don't flame just ask me to clarify.