主题中讨论的其他器件: LMK04821
我在双站点 ATE 最终测试板上使用 LMK04828。 当 CLKIN1上的输入为700MHz/13dBm 时、我在 SCLKOUT 上看不到任何输出。 原理图随附。 以下是 SPI 写入。
SPI::wspi_lmk (0x138、0x40); //VCO 多路复用器= CLKIN1
SPI::wspi_lmk (0x146、0x10); //CLKin1_EN = 1
// DCLKoutX_DIV 的分频器
SPI::wspi_lmk (0x110、0x04); //S1 FPGA REFCLK_1.
SPI::wspi_lmk (0x100、0x04); //S1 FPGA REFCLK_2.
SPI::wspi_lmk (0x118、0x04); //S2 FPGA REFCLK_1.
SPI::wspi_lmk (0x130、0x04); //S2 FPGA REFCLK_2.
//输出格式
SPI::wspi_lmk (0x107、0x11); //S1 FPGA SYSREF = LVDS、REFCLK_2 = LVDS
SPI::wspi_lmk (0x10F、0x60); //S1 DUT SYSREF = LVPECL 2000mV
SPI::wspi_lmk (0x117、0x04); //S1 FPGA REFCLK_1= HSDS 10mA
SPI::wspi_lmk (0x11F、0x04); //S2 FPGA REFCLK_1= HSDS 10mA
SPI::wspi_lmk (0x127、0x60); //S2 DUT SYSREF = LVPECL 2000mV
SPI::wspi_lmk (0x137、0x11); //S2 FPGA SYSREF = LVDS、REFCLK_2 = LVDS
SPI::wspi_lmk (0x12F、0x00); //nC 断电
//断电
SPI::wspi_lmk (0x116、0x30); //S1 FPGA REFCLK_1.
SPI::wspi_lmk (0x106、0x30); //S1 FPGA REFCLK_2.
SPI::wspi_lmk (0x11E、0x30); //S2 FPGA REFCLK_1.
SPI::wspi_lmk (0x136、0x30); //S2 FPGA REFCLK_2.
//选择 SDCLKOUTy 输入
SPI::wspi_lmk (0x104、0x20); //S1 FPGA SYSREF
SPI::wspi_lmk (0x10C、0x20); //S1 DUT SYSREF
SPI::wspi_lmk (0x124、0x20); //S2 DUT SYSREF
SPI::wspi_lmk (0x134、0x20); //S2 FPGA SYSREF
// Sysref 分频器
SPI::wspi_lmk (0x13A、0x1);//div x 480
SPI::wspi_lmk (0x13B、0xE0);
HSx_helper::StartHsxClk (4、Freq、13); //LMK_CLKIN:13dBm
WAIT_TIME (100us);
SPI::wspi_lmk (0x144、0xFF);
SPI::wspi_lmk (0x139、0x3);
//加电
SPI::wspi_lmk (0x02、0x0);