Help needed choosing a serial DAC chip

19 Dec 2011

I'm having trouble finding a serial DAC that meets my needs. Hopefully someone here can help.

Here are my (demanding) requirements:

1) MUST have a serial interface compatible with the mBed LPC1768 hardware. I'm writing custom drivers so it doesn't have to be compatible with the standard libs.

2) MUST handle at least 50Mhz clk (25Mbaud)

3) MUST be 12bits resolution with a maximum 16bit command/data word length.

4) Should be a quad unit, a dual or in a pinch a single channel will do.

5) Be reasonably priced (whatever that means).

So far the only thing I can find that comes close are ones with a LVDS interface and I'm not sure I can hook them to the LPC1768.

Any recommendations will be greatly appreciated.

19 Dec 2011

50 Mhz clk is very high for 100 MHz mbed. Forget about using regular pins that you toggle in software. The only thing that comes close is probably the spi bus. You may have to drive it using DMA.

Google for +DAC +spi +50Mhz will give you a number of hits.

For example the AD5025/AD5045/AD5065, dual 12-/14-/16-bit DACs. The command + dataword is however 32 databits per sample.