Question about source current and sink current

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#1
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HI, I'm a newbie.
I want to program my mcu.
but at the first step,
I have problem.
I saw some site which is linked at "NEWBIE? START HERE"
and they just connect MCU to programmer. so I connected it and I did something..(probably something wrong.) It made the chip died.
In this chip, I provide voltage to Vfet
and Atmega 406 internally regulate the voltage to 3.3v - Vref.
but.. I did something wrong and thip died and
Vref went up to more than 5V.
I connected avr dragon to the atmegaa 406 so.. my dragon was also dead.
I wonder what I did. and I thinked again.
I looked through the data sheet and
I have question about sink current and source current.
According to datasheet,
Sink current should not be exceed 5mA, 20mA(total,DC)
source current should not be exceed 2mA.

so... Is it okay to connect atmega 406 to dragon directly?
should I put register between the connection of
dragon and MCU?
If I should, how can I seect the value of register?
and I connected the chip to power supply with
register 10kohm (in serial).
and I found that directly connecting MCU to power supply also worked.
could I use atmega 406 with connecting power supply directly? Is it safe?
thank you so much!! :D
Have a nice day!!

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Total votes: 0

Dragon holds the AVR in reset while it operates (ISP programming or debug) and neither supplies nor takes anything but negligible current. - just connect it direct as described in its user manual.