Re: [Discuss-gnuradio] Hardware extending

[Tomas D.]

On 2011.07.25 10:48, Farhad Abdolian wrote:

Hi,

I would be careful buying components from E=bay for anything other than simple prototypes. These components maybe cheap on e-bay but if you are serious on making this a working design, you may end up spending more time dealing with ESD damaged products, or those you can not replace in the future.

It can be worth spending a bit more (or even ask for free samples if you work for a large company) than saving a few $s during the initial design.

Just my 2c learned from previous mistakes,

Farhad

Hello,
if we are talking about a board, that potentially could be used by more than 10-20 persons, then yes, we have to consider using proper hardware.
Let's have a look to the minimum requirements that we have in USRP2:
ADC: 2 channels, 100MSPS, 14bits, SFDR 88dB
DAC: 2 channels, 100MSPS, 16bits, SFDR 80+ dB

Now devices on USRP2 are:
ADC: Linear Tech. LTC2284 (2ch, 105MSPS, 14bit)
Price @ Digikey: 147.6USD
Price @ Farnell: ~200USD
This one is barely on stock.

DAC: AD AD9777 (2ch, 160MSPS interpolating up to 400MSPS, 16bit, TxDAC+)
Price @ Digikey: 59.87USD
Price @ Farnell: 82.5USD

Now lets consider other choices:
ADC: TI ADS62P48 (2ch, 210MSPS, SFDR 85dB) - price @ Digikey: 176.18USD
ADC: TI ADS6244 (2ch, 105MSPS, SFDR 81dB) - price @ Digikey: 88.7USD
ADC: TI ADS6245 (2ch, 125MSPS, SFDR 83dB) - price @ Digikey 110.25USD
ADC: TI ADS4246 (2ch, 160MSPS, SFDR 87dB) - price @ Digikey 116.25USD
And TI are previewing ADS4249 (2ch, 250MSPS, SFDR 80dB) - price N/A

Prices are in quantities of single chip only!

I've not checked AD, Linear, etc. The question is: do we stick to the current hardware or search for a new one?

P.S. I am not sure if I am correct using USRP2 basis. Maybe I should switch over to N210 datasheet?

Sincerely,
Tomas D.