Chomsky Posted September 22, 2011 Report Share Posted September 22, 2011 I've done the PIC burner now for the 2nd time but only the yellow LED goes on when I connect it to the power supply. Is that normal or not? Quote Link to comment Share on other sites More sharing options...
nuke Posted September 22, 2011 Report Share Posted September 22, 2011 the "green" power led has to be lit when psu is connected...do u get +5 after 78L05 ? led´s reversed? Quote Link to comment Share on other sites More sharing options...
Chomsky Posted September 22, 2011 Author Report Share Posted September 22, 2011 yes. I measure 5V after 78L05. What do you mean by reversing the LEDs? Do you mean I should stick them in with the wrong polarity? Quote Link to comment Share on other sites More sharing options...
nuke Posted September 23, 2011 Report Share Posted September 23, 2011 (edited) yes. I measure 5V after 78L05. What do you mean by reversing the LEDs? Do you mean I should stick them in with the wrong polarity? hehe...no, don´t stick them in the wrong direction, but maybe they are reversed... i´m just trying to minimise the possiblities of false operations... ;) so when u got 5v after 78L05, the green powerled must be lit, since its only connected to 5v-rail and gnd via a resistor. mmm...btw , what do you mean with "yellow" led...from the schematics? or the pics on ucapps?... on the pictures the lit "green" powerled looks a bit yellow... Edited September 23, 2011 by nuke Quote Link to comment Share on other sites More sharing options...
Chomsky Posted September 23, 2011 Author Report Share Posted September 23, 2011 When I connect one of the pins of the 470 Ohm resistor before the green LED or the pins of the green LED to ground, I can measure 5 Volts, But it seems that somewhere after the green LED a connection to ground is missing. Maybe I have to connect the PIC board to the computer to get it working? Quote Link to comment Share on other sites More sharing options...
nuke Posted September 23, 2011 Report Share Posted September 23, 2011 When I connect one of the pins of the 470 Ohm resistor before the green LED or the pins of the green LED to ground, I can measure 5 Volts, But it seems that somewhere after the green LED a connection to ground is missing. Maybe I have to connect the PIC board to the computer to get it working? the anode of the led should be connected to +5V, while the cathode is connected to 470 Ohm...the 470 Ohm resistor goes to ground. so the led isnt connected directly to ground, only via the resistor. check the schems again. Quote Link to comment Share on other sites More sharing options...
RoyalScam Posted September 24, 2011 Report Share Posted September 24, 2011 Did you make this PC Board yourself, toner transfer or some other method? The reason I ask is that if you printed out the PCB layout in Eagle, without doing a rat's nest operation, the ground plane would not be on the circuit board. Therefore no ground for green LED. Scam Quote Link to comment Share on other sites More sharing options...
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