Must the power supply be 13.5V?

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Jonathan
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Must the power supply be 13.5V?

Post by Jonathan »

I was just wondering if the board has a regulator to output 5V to the PIC, then why does it need a high voltage of 13.5V power supply? Can it be lower just to operate the PIC?
Surely this bigger voltage difference means a larger heat dissapation from the regulator?

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Benj
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Re: Must the power supply be 13.5V?

Post by Benj »

Hello

We use a 13.5V supply because the PICmicro devices require at least 12V to allow them to be programmed. The extra voltage is recommended because there is a small voltage drop across the bridge rectifier. If you simply want to run the device then you can power from USB 5V or you can use approx 6-7V power supply.

Jonathan
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Re: Must the power supply be 13.5V?

Post by Jonathan »

Benj wrote:Hello

We use a 13.5V supply because the PICmicro devices require at least 12V to allow them to be programmed. The extra voltage is recommended because there is a small voltage drop across the bridge rectifier. If you simply want to run the device then you can power from USB 5V or you can use approx 6-7V power supply.
I tried 9V and one of the small chips near the regulator got hot.

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Re: Must the power supply be 13.5V?

Post by Benj »

Hello

These chips should not be getting hot even if you throw in 15V to the board. Have you attached any of your own circuitry to the board or anything like this. Also can you make sure that only one PICmicro device is inserted into the board, this has been a problem in the past.

What are you using as a power supply?

Jonathan
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Re: Must the power supply be 13.5V?

Post by Jonathan »

Thank you for your reply.

Just to reassure you, I normally use 13.5V supply using your adaptor ordered from Matrix Multimedia.

Then I reduced the voltage to 9V by changing the selector on the adaptor, just to see if it would still operate. It did but thats when chips U3 or U6 on the board got hot.

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