Tool/software:
Hello,
I am using an FPGA development board to communicate with a DAC81001 board via SPI. The DAC can read and write normally. However, when changing the DAC register values, I find that the voltage on the OUT pin (analog output) shows no change and remains around 0V. Can you help me analyze the reason?
In my schematic design, VDVDD=VIOVDD=3.3V, VREFPF=10V, and VREFPN=-10V. The schematic design is shown below.
The FPGA program sets fSCLK=12.5MHz, and the timing of SYNC/SCLK/SDIN/LDAC/CLR signals meets the specifications. Test results are shown below.
CS / SCLK / SDI / SDO / LDAC / CLR / Analog output :
The FPGA program performs 317 consecutive register operations on the DAC81001, with the 15th to 317th operations writing different values to the DAC-DATA register.
The program is shown below. The current value of i_pw_rd_data is the data from line ro_pw_rd_addr in the text file.
The measured SDI and SDO values are shown below.
As shown in the above figure, the result read from the STATUS register is 85000720h.
