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Can help me to check the pcb route i drawn

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M

McMurry

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check in pcb version

I need both 3.3V and 5V in my circuit. hence, im using regulator lm1117 and lm7805.
i soldered the voltage regulator with the dc jack and capacitors, then i checked the voltage output from both voltage regulator.

lm1117 is working fine (has output of 3.3V) but lm7805 is getting HOT at the instant i plug to the dc jack.

is there something wrong with my PCB drawing?
i have checked the drawing. and found a mistake on the grounding. but when i add solder according to the brown line in the circle, same problem exist.

is there any other mistake i made with the lm7805 routing?
 

how can i check pcb output

If a regulator is getting too hot, thjen it is almost certainly a short elswhere in your circuit. This will cause the circuit to draw more current than it should making for a hot regulator.
This of course is assuming that you have have worked out hte current draw of your circuit correctly, and installed an appropriate regulator.
 

    M

    McMurry

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lm1117 hot

The error seems pretty obvious to me. For the LM7805, Pin1 is input, Pin2 is GND, and Pin3 is output. You have the output pin, pin3, connected to ground - a dead short.

The trace connected to pin2 of the capacitor just below the LM7805 (on the output pin) should go to pin1 of that capacitor instead (I mean the ground trace that loops in from the bottom, not the short trace from pin3 of the 7805).
 

    M

    McMurry

    Points: 2
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