Enclosed is a schematic of a power supply I designed to source a 12 volt DC 1.5 amp motor and a 5 volt requirment for a 16F887 microprocessor. I'm using two supply rails with a common ground. The input seems adequate (18 volt DC 3.5 amp) and I'm reading 12 and 5 volts on the regulator outputs. The microprocessor VDD readings also indictae 5 volts and I can jump from the 12 volt rail to power the motor. However, I 'm struggling getting the microprocessor to run on the PCB.
The programming syntex works on the proto board with both the external and internal oscillators and I'm following the manufacturer's perscribed components for the oscillator. I also tried the internal OSC with no success on the PCB.
I'm trying to eliminate possible problems and need another set of eyes on the power supply to ensure I'm not missing something.
Sure would appreciate some assistance.
Roger
The programming syntex works on the proto board with both the external and internal oscillators and I'm following the manufacturer's perscribed components for the oscillator. I also tried the internal OSC with no success on the PCB.
I'm trying to eliminate possible problems and need another set of eyes on the power supply to ensure I'm not missing something.
Sure would appreciate some assistance.
Roger
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