DAC38RF85: DAC38RF settings

Eugene Volkov

Part Number: DAC38RF85

Hello.

I need generate signal with 600 MHz bandwidth, in the 1.2GHz carrier friquency.

If I understand correctly, i need genegate quadrature signal in zero carrier frequency, with sample frequency 600MHz. In the DUC, need set NC0 frequency to 1200MHz.

SERDES rate, for this purpose - 1.25*(2/8)*600*16 = 3000MHz. Thith interpolation 12 DAC clk - 7200MHz.

But, FIR filers passband BW is 0.4 x Finput. And I don’t understand how to get a signal with a required bandwidth.

over 4 years ago

0 Neeraj Gill over 4 years ago

TI__Mastermind 20541 points

Hi Eugene,

We are looking at your question and will get back to you.

Regards,

Neeraj

0 Eugene Volkov over 4 years ago in reply to Neeraj Gill

Intellectual 410 points

Hi Neeraj Gill,

Waiting for your reply.

I use BPSK modulation.

How can I understand, the maximum bandwidth for DAC38RF85 is a 0.4 of input data rate, or 1250*0.4 = 500MHz. If input signal is complex , maximum bandwidth of output signal, must be 1250*0.8 =1GHz.

0 jim s over 4 years ago in reply to Eugene Volkov

TI__Guru* 91947 points

Eugene,

You will need to increase your DAC input data rate to 750MHz to get 600MHz of bandwidth. This will require using complex data. With the data rate at 750MHz, the passband of the filter will be 750MHz x 0.4 = 300MHz plus the complex image of -300MHz = 600MHz of total bandwidth. This will require the DAC sample rate clock to be at 9000MHz with an interpolation of 12x.

Regards,

Jim

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DAC38RF85: DAC38RF settings