Anyone programmed a 328p QFN?

Hello I have a design that I wanted to make small so i used a QFN package of the atmel 328p chip. It has 32 pins like its QFP package but for the life of me I cannot get it to be seen by avrdude or Arduino IDE. Both have problems even detecting it. I'm using USBtinyISP to do the spi interface between computer and chip. I've looked online for help but I cannot find anyone who has said that they have done this with the QFN package. Also is it posibal to do with the QFN or am I banging by head against the wall? Any help would be VERY apriciated!

The Nano uses the 32 pin package, try telling the compiler that you're using one.

The issue only is that of mapping pins to ports, which is done in one of the iomxxx files, linked at compile time. If you do all the mapping yourself (mnemonics to addresses, refer to the datasheet) you don't need those files. The other issue is that during compile, a 'signature' is sought which can lead to an aborted attempt if not found. There is a command line switch to turn this checking off, -F if I'm not mistaken. Much the same problem occurs when using the China clones, especially with the CH340G chips.


QFN is just a smaller TQFP, yes? I think even the pinouts are the same. Same '328P die inside the plastic package.

Are you getting it bootloaded?

I've had one that Arduino said accepted the boot loader. But I cannot put programs on it.

Are you using a 16 MHz crystal or resonator? If not you will need to set the fuses to use the 8 MHz internal RC clock.

If the fuses have been set to expect a crystal you will need to provide a crystal or resonator or external clock to allow programming.

So I got a QFN to accept the boot loader and a program through usbtinyisp using the arduino ide. Success!! I had to build a second minimal circuit to do it though. (16mhz with the trimming caps and all). The same circuit is set up on my primary board but for some reason whenever I reflow a qfn into it the chip and crystals and caps only draw 5mA when powered. In the working circuit the same qfn will take 15-18ma while running a small Arduino scetch. Does anyone know why this would happen. Both the circuit that works and the circuit that only operates at 5mA are the same.