Introduction -
The evaluation boards are for users to evaluate the performance of the high-speed direct digital
frequency synthesizer, Euvis DS85x. The inputs include 32-bit single-ended digital signals
VIN0 ~ VIN31 for frequency control, reset signal RST for accumulator reset, strobe signal STRP to strobe
the frequency control input, and a pair of differential clock signals. All the input signals except
the clock signals are controlled by a PC through the USB interface. The clock input pair allows the clock
source to be presented in either single-ended or differential form with SMA connectors. The outputs of
the evaluation board consist of a pair of differential analog outputs OUTP/OUTN and the accumulator’s
carryout signal COUT.
The evaluation board features a USB-compliant interface through which a companion application
program provides users convenient ways to control the DDS.
Key Features
- 32-bit frequency tuning word
- On chip DAC with 10 bit linearity
- Complementary analog waveform outputs with 50 Ω back terminations
- Carry bit RF output from phase accumulator
- Worst SFDR > 50 dBc (DC to 1-GHz Bandwidth) at a 2 GHz clock rate
- TTL/CMOS digital pattern control input
- Reset (RST) pin to initiate phase 0 starting state
- High speed strobe LVPECL or LVDS compliant inputs (STRP/N) to change DDS output frequency
- 64-pin QFN package
Board Diagram
