USBTinyISP circuit question

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While shopping around for an USBTinyISP programmer I came across this device.

Micro USB Tiny AVR ISP 5V ATtiny44 USBTinyISP Programmer For Arduino Bootloader
http://r.ebay.com/iTehVN

​The schematic has a VCC tied to GND via 10K resistor and I was wondering why? It this a host USB min current requirement or something on the chip side?

 

 

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You're right, that 10K goes across the power.

Although the schematic and the photo don't agree 100%. The USB resistors are different values and the LED/R aren't on the schematic.

 

There is no requirement that a USB device draws power.

A simple proof of that is all the USB hubs that exclusively use external power.

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I am sure that this little board will probably work.   Its biggest selling point is the 3x2 header.

 

However you can buy a genuine Chinese USBASP for about the same money.   And most of these can supply 3.3V or 5V as required.

These tend to come with a 5x2 header and 10-way ribbon cable.    You need to make or buy an adapter for 3x2.

 

David.

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Does this device load the "opti" bootloader program into a Mega328P so that can be used with the Arduino IDE when TX,RX,gnd, Vcc, and DTR are connected to the Mega328P?   Is the bootloader code stored on the IC? 

Or is this simply a version of USBasp on a smaller PCB?