Continuing to my question here: High Speed ADC ?
I purchased a few of the AD9059 (it was $30 each ), but I must say: this chip is AWESOME !!!!!
I connected it to my Intronix LogicPort Analyzer, and I basically I turned my digital analyzer into an analog oscilloscope also.
So, the questions:
1) I used 2 * LM7805 power regulators, one for VD power, and another for VDD power. The thing that I'm worried about is that the AD9059 is getting a little worm to the touch, and also the LM7805 power regulator that goes to the VD input is a little more worm than the ADC chip, but not too hot so you can't touch it.
I was not expecting that one chip that small (especially an ADC) to draw so much power to get a LM7805 power regulator worm at all.
The data sheet says "Low Power: 400 mW Typical", is that enough to make the LM7805 worm ?
2) I tried to change the VREF to 5V, so I connected the VREF (Pin 2) to VD (5V) (I also tried VDD which is 5V also), and the thing went DEAD ! as soon as I disconnected the VREF from the VD, then it worked fine after that...
So my question is, how can I change the VREF then ?
3) Is there a chip that can output a preset number of frequencies ?
What I mean is, I want to give 60Mhz, and to give out, 50MHz, 40MHz, 30MHz, and so on ?
I want to be able to change the frequency that goes in the ADC.
4) Is there an Opto-isolator that can go at 60MHz (or higher) so that I can isolate the ADC output ?
5) Why do they use the 74ACQ574 chip in the Evaluation Board Schematic ? does that act as an Opto-isolator ? (It does not look like it...)
I purchased a few of the AD9059 (it was $30 each ), but I must say: this chip is AWESOME !!!!!
I connected it to my Intronix LogicPort Analyzer, and I basically I turned my digital analyzer into an analog oscilloscope also.
So, the questions:
1) I used 2 * LM7805 power regulators, one for VD power, and another for VDD power. The thing that I'm worried about is that the AD9059 is getting a little worm to the touch, and also the LM7805 power regulator that goes to the VD input is a little more worm than the ADC chip, but not too hot so you can't touch it.
I was not expecting that one chip that small (especially an ADC) to draw so much power to get a LM7805 power regulator worm at all.
The data sheet says "Low Power: 400 mW Typical", is that enough to make the LM7805 worm ?
2) I tried to change the VREF to 5V, so I connected the VREF (Pin 2) to VD (5V) (I also tried VDD which is 5V also), and the thing went DEAD ! as soon as I disconnected the VREF from the VD, then it worked fine after that...
So my question is, how can I change the VREF then ?
3) Is there a chip that can output a preset number of frequencies ?
What I mean is, I want to give 60Mhz, and to give out, 50MHz, 40MHz, 30MHz, and so on ?
I want to be able to change the frequency that goes in the ADC.
4) Is there an Opto-isolator that can go at 60MHz (or higher) so that I can isolate the ADC output ?
5) Why do they use the 74ACQ574 chip in the Evaluation Board Schematic ? does that act as an Opto-isolator ? (It does not look like it...)
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