Draw PCB for the first time, my students encountered many problems during learning, now the board found in voltmeter buzzer gears VCCA and 3. 3 v there was a noise, schematic diagram as shown in figure, because the R10 resistance is too small is considered directly connected?

Board in the state is now 1117 stabilized after the electric hot power light is not on, remove the ST chip after the board can electricity again, once thought that the chip is broken, bought the new chip welding up also not line, remove the chips to check what also didn't short circuit, depressed ah, do a lot of knowledge on board, some problems cannot solve the heart cool, really help bosses

CodePudding user response:

R11 meet VCC3.3 R12 connect GND VCC3.3 short circuit caused by the take off the R12

CodePudding user response:

Yes 99 pins to look at, not equal to 3.3 connect to GND together?

CodePudding user response:

reference 1st floor billtest36 response:

R11 meet VCC3.3 R12 connect GND VCC3.3 short circuit caused by the take off the R12 can

Well, this problem has been solved before, forget illustrates the first,

CodePudding user response:

, full PIC, first determine where is short circuit 1, short circuit 2 chip circuit itself, is on the chip after peripheral short circuit (such as the chip is not empty gave the signal to the circuit conduction

CodePudding user response:

reference 4 floor lapu response:

,

, full PIC is determine where the short circuit 1 first, short circuit 2 chip circuit itself, is a peripheral short circuit (such as after the chip is not empty gave the signal to the circuit conduction

Schematic diagram or? Chip inspection such as the state now is not short circuit, circuit board without short circuit, as long as when welding chip welding on 3. 3 v &gnd 3. 3 v grounding short circuit,
Me all the chip welding, secant want to look at the peripheral circuit where the short circuit, as long as the chip a few 3. 3 v any final cut and peripheral circuit, circuit boards and chips are not short circuit, what is this

CodePudding user response:

reference 5 floor potato mash reply:

Quote: refer to 4th floor lapu response:

,

, full PIC is determine where the short circuit 1 first, short circuit 2 chip circuit itself, is a peripheral short circuit (such as after the chip is not empty gave the signal to the circuit conduction

Schematic diagram or? Chip inspection such as the state now is not short circuit, circuit board without short circuit, as long as when welding chip welding on 3. 3 v &gnd 3. 3 v grounding short circuit,
Me all the chip welding, secant want to look at the peripheral circuit where the short circuit, as long as the chip a few 3. 3 v any final cut and peripheral circuit, circuit boards and chips are not short circuit, this is what circumstance

Or on the principle diagram of the full PIC

CodePudding user response:

refer to 6th floor lapu response:

Quote: refer to the 5 floor potato mash reply:

Quote: refer to 4th floor lapu response:

,

, full PIC is determine where the short circuit 1 first, short circuit 2 chip circuit itself, is a peripheral short circuit (such as after the chip is not empty gave the signal to the circuit conduction

Schematic diagram or? Chip inspection such as the state now is not short circuit, circuit board without short circuit, as long as when welding chip welding on 3. 3 v &gnd 3. 3 v grounding short circuit,
Me all the chip welding, secant want to look at the peripheral circuit where the short circuit, as long as the chip a few 3. 3 v any final cut and peripheral circuit, circuit boards and chips are not short circuit, this is what circumstance

Or a full PIC on schematic diagram

Well, have been sent to your private in 123456

CodePudding user response:

R11, R12 is not equal to the power supply directly to the ground short circuit?

CodePudding user response:

refer to the eighth floor worldy response:

R11, R12 is not equal to the power supply directly to ground short circuit?

This has been solved before, didn't change principle diagram, forget the first

CodePudding user response:

Check your chip packaging, pin definition if you have any questions,

CodePudding user response:

R10 only 10 ohms, multimeter buzzer will call normal