Other Parts Discussed in Thread: DAC34SH84, DAC5675A-SP
Hi All,
For one of my designs I need to generate two independent DAC output voltages (with few discrete steps only) @ 400 MHz and above. Both the outputs should change simultaneously with the DAC clock.
Initially I used a TI 2-Channel DAC EVM thinking that this will give me two outputs which will change simultaneously. But I realized that the Ch1 and Ch2 outputs are 1/2 clock apart as the Input Data interface is LVDS DDR.
After checking the other DACs from TI, I found that the DAC34SH84 is a high speed DAC (1.5 GSPS) with two separate 16 bit LVDS inputs. The Ch1 and Ch2 are time multiplexed DDR (Data Port 1) and similarly the Ch3 and Ch4 are also time multiplexed DDR (Data Port 2 ).
I have three questions now.
1. As there are two separate input data ports in the DAC34SH84 (Ch1 and Ch2 are time multiplexed on Input Data Port 1 and similarly Ch3 and Ch4 are time multiplexed on Input Data Port 2) will I get simultaneous output changes on Ch1 and Ch3 (and similarly on Ch2 and Ch4) ? Will the Ch1 and Ch3 ( similarly Ch2 and Ch4) outputs change with the same edge of the DAC clock ?
2. The data sheet says the rise/fall time for these DAC outputs is 300ps. Will I get the same rise/fall time on the DAC34SH84 EVM outputs ( as the outputs are transformer coupled ) ?
3. Can somebody in TI actually test the DAC34SH84EVM and confirm me the rise/fall time for the EVM outputs ?
