Arduino Micro Circuit Diagram Knowledge Questions

[charlesli]

I would like to ask a question about this voltage regulator circuit.

1. It contains a voltage regulator chip, MIC5219-5.0, can this chip be replaced by 7805? Because I want to do the test on the breadboard. Can you provide the circuit with 7805, and what components are needed?
2. please LM7805, L7805CV linear, what is the difference between these 7805?
3. the picture contains a D2, what kind of diode is it? I'm not sure which diode I should buy when I buy components for this.
4. If a good Micro is connected to the phone USB, is this regulator circuit needed to control the output voltage at 5V?

 

[Pommie]

The diode is to stop the input voltage appearing on the USB socket. As raw can be up to 16V then the USB port would probably smoke. You can just do a straight swat with a 7805 but it might get hot. If you draw the full 500mA then the 7805 will dissipate (16-5)*½ = 5.5W so will need a heatsink. Assuming you're going to power it via the USB socket then a regulator isn't really required.

Mike.
Obviously, the 7805 has in, out and gnd - anfd these are the only ones needing connected. Caps etc should be fine.

 

[tumbleweed]

FWIW, the recommended max input voltage of the MIC5219 is 12V, not 16V, but as Pommie points out ANY linear regulator is going to have a hard time giving you 500mA out with that much voltage in.

Even with a heatsink, 5W will generate a LOT of heat. Realistically, you're looking at more like 1W out, so at 16V in that's about 100mA max, and even that's going to get pretty darn hot.

 

[charlesli]

The diode is to stop the input voltage appearing on the USB socket. As raw can be up to 16V then the USB port would probably smoke. You can just do a straight swat with a 7805 but it might get hot. If you draw the full 500mA then the 7805 will dissipate (16-5)*½ = 5.5W so will need a heatsink. Assuming you're going to power it via the USB socket then a regulator isn't really required.

Mike.
Obviously, the 7805 has in, out and gnd - anfd these are the only ones needing connected. Caps etc should be fine.

Thank you, you solved my problem perfectly.