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Voltage level on PIC VDD pin.

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Hi, I have a question about the VDD pin.

I know that the VDD pin on the PIC does take maximum +6.5V and maximum current of 250 mA. Isn't it still possible to connect a +9V battery to this pin without burning the darn thing, by adding a resistor to bring down the currency with this calculation: (+9V-+5V) / 0,250A = R = atleast 16Ω Is this workable or will it still break the PIC? Am I even thinking/and making the right calculation here? And Isn't the currency more dangerous than the voltage level?

Still learning..

Regards

/ Morgan
 

Morgan
The PIC16HV series will work this way. the 250mA is not constant and will depend on the work the PIC does. So your calculation does not work.
Thanks
Hari
 

harimelath said:
Morgan
The PIC16HV series will work this way. the 250mA is not constant and will depend on the work the PIC does. So your calculation does not work.
Thanks
Hari
Click to expand...

Hari, thank you for your response.
Yes, I was recently taught by wp100 that I'll need a voltage regulator like the one in my PIC programmer. :)

Soo this is the way to do it, I didn't connect my PICs to the right voltage source before but I certainly will further on thanks to you guys.

Thank you for your guidance

/ Morgan
 

I know that the VDD pin on the PIC does take maximum +6.5V and maximum current of 250 mA.
Click to expand...
You're apparently confusing absolute maximum ratings and specified operation conditions. No PIC is specified
to operate above 5.5V supply voltage. Keeping the voltage below 6.5V avoids permanent damage, but doesn't
guarantee correct operation.

The said HV types have an internal shunt regulator, but the supply voltage for correct operation is limited to 5.5V
as well. By adding a series resistor, you can power it from a higher voltage, but involving a lot of dissipated power.
Using a standard voltage regulator, e.g. 7805 is always preferable.
 

FvM said:
You're apparently confusing absolute maximum ratings and specified operation conditions. No PIC is specified
to operate above 5.5V supply voltage. Keeping the voltage below 6.5V avoids permanent damage, but doesn't
guarantee correct operation.

The said HV types have an internal shunt regulator, but the supply voltage for correct operation is limited to 5.5V
as well. By adding a series resistor, you can power it from a higher voltage, bunt involving a lot of dissipated power.
Using a standard voltage regulator, e.g. 7805 is always preferable.
Click to expand...

FvM, yes you made me read more about it and I've sorted it all out now.. thanks

/ Morgan
 

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