thunderdog
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Hi,
I have "cut-and-paste" a working circuit to save some time. Please see the attachment for details. The circuit seems to be designed to use the ULN2003 to drive several TIP32 PNP transistors, which in turn drive several relays. The pins named "uP Pin" are connected to various I/O pins on the microcontroller. My problem is that I can't seem to get an output (locations Out1, Out2, Out3). At most, I get about 1.5volts. The only part of the circuit that seems to be working is the one driving the 2N4402 xistor. The output (J20) does toggle between the 12V and gnd. Can anyone explain a bit better what's going on here or why I can't seem to get the proper outputs ?
Thanks.
I have "cut-and-paste" a working circuit to save some time. Please see the attachment for details. The circuit seems to be designed to use the ULN2003 to drive several TIP32 PNP transistors, which in turn drive several relays. The pins named "uP Pin" are connected to various I/O pins on the microcontroller. My problem is that I can't seem to get an output (locations Out1, Out2, Out3). At most, I get about 1.5volts. The only part of the circuit that seems to be working is the one driving the 2N4402 xistor. The output (J20) does toggle between the 12V and gnd. Can anyone explain a bit better what's going on here or why I can't seem to get the proper outputs ?
Thanks.