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Digital to analog converter

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isamel85

Programmer
Nov 4, 2011
5
CA
Hello,

Actually I am looking for a digital to analog converter (preferably an evaluation board) in order to connect an FPGA with a RF signal generator N9310A (he plays the role of an I and Q modulator and includes two inputs analog I and Q on rear panel and he can transpose the two analog signals to an RF signal).

In the FPGA, I have a baseband transmitter chain with two I and Q outputs, the internal blocks are clocked on the clock frequency of 1 MHz, but the last two blocks (upsampling with a factor of 8 and the digital filter in transmission) working on an 8 MHz clock. So the two outputs of filters with 10 bits each (I and Q) are the outputs of the main transmitter.

So I need an evaluation board for a digital to analog converter which has the following characteristics:
- 10 bit resolution
- Rate of 8 MSPS. Is it correct? Is it possible to select a higher rate e.g. 125 MSPS?
- Dual TxDAC for the two channels (I and Q)
- Parallel interface with digital signals from FPGA
- Analog output range or the output reference voltage must be compatible with analog I and Q inputs of the RF signal generator.

Knowing that the analog I and Q inputs of the RF signal generator has the following characteristics: I / Q modulation (Option 001 only)
Operating mode External I/Q inputs

VSWR < 1.5

Full scale input 0.5 Vrms

Modulation frequency range DC to 20 MHz At 3 dB points

Carrier suppression 40 dBc Typical; modulation frequency = 10 kHz

QPSK EVM 3% Typical; 1 Msps; 0.22 RRC filter

GMSK phase error 1.2 °rms Typical; 1 Msps; BT = 0.5

Connector and impedance BNC female; 50 Ω Rear panel

So if anyone who can help me to choose this converter.

Another alternative, is there a VHDL description of a digital to analog converter based on a first order Sigma Delta modulator (a version that works)?

Please I need a help.

Thank you.

Best Regards,
Isamel
 
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