The steps for testing the channel-to-channel skew measurement are as follows:
- Emulate the hardware setup as shown in Figure 7-3, then provide the input signal to the J12 and J29 SMA connectors of channel 1 and 3 of the TIDA-01022 design through a variable band-pass filter and 2:1 splitter.
- Connect the high-speed USB3.0 and USB2.0 cables to the capture PCs.
- Configure the TSW14J56 capture card as master and slave configuration mode:
- Connect the master TSW14J56, J7 (TRIG OUT –A) to J13 (TRIG IN) using a high-speed SMA cable for master self-triggering.
- Connect the master TSW14J56, J8 (TRIG OUT –B) to J13 (TRIG IN) of the slave TSW14J56 module using a high-speed SMA cable.
- Provide a 12-V, 4-A DC supply to the power connector (J55) of TIDA-01022 and provide a 5-V supply to the TSW14J56 capture card.
Note: As Figure 7-3 shows, the length of the cable must be length matched
To measure the multichannel skew, configure the following using the HSDC TID GUI:
- Use the J32 connector to program the LMK61E2 device at 33.75 MHz using the USB2ANY programmer associated with the LMK61E2 Oscillator Programming Tool. Set the device address as 0x5A before programming.
- Program the LMK04828 in 0-delay PLL mode at a 33.75-MHz SYSREF frequency to provide the SYSREFREQ and SYNC signals along with this 33.75-MHz OSCout as a reference to the LMX2594.
- The LMK04828 also generates the FPGA reference at 270 MHz, the FPGA core clock at 270 MHz, and the FPGA SYSREF at 33.75 MHz for the FPGA capture card.
- Program the LMX2594_A and LMX2594_B for a 2.7-GHz DEVCLK and 33.75-MHz SYSREF at
33.75 MHz. - Configure ADC12DJ3200 JMODE-2 (dual-channel mode) by loading the configuration file in the low-level page.
Establish the JESD204B link using HSDC Pro GUI:
- After powering the TSW14J56, establish a connection with the dual-channel mode (JMODE2).
- Provide the data rate sampling frequency of the ADC output and the ADC input target frequency.
- After establishing the JESD204B connection, feed the input signal to channel 1 (J13) and channel 3 (J76).
- Apply a trigger at the slave capture board and then click the capture button on the master board.
- Export both ADC1 and ADC2 data then extract the phase and amplitude information from the spectrum using the MathLab® program and plot the data in the time domain for a channel-to-channel skew measurement.