Jitteris a random variation of the output clock. It is caused primarily by AVDD/AGND and substrate noise perturbing the VCO(Voltage Controled Oscillator) within the PLL. It can also be caused by excessive jitter on the REFCLK input. Output jitter is defined in three ways: period jitter. dut...
DCM_Base,PLL_Base
CONSTITUTION:A counter 20 and an up-down counter 21 apply count in the same direction in the transient state where the phase difference between the reference clock REFCLK and the output clock CMPCLK is increasing. As a result, the count of the counter 21 reaches 0 or 15 earlier and a ...
86External memory interface clock output jitter specifications use a different measurement method, which are available in theMemory Output clock Jitter Specificationstable. 87This specification is limited by the I/O maximum frequency. The maximum achievable I/O frequency is different for each I/O stan...
总的来说PLL的应用多,DLL则在jitter power precision等方面优于PLL。 DLL数字电路与PLL模拟电路实现时有精确的时序,而数字电路实现时:抗噪声,低功耗,抗抖动,移植性好。 PLL的振荡器有不稳定,相位偏移的积累而DLL技术稳定,没有累计相位偏移。因而在延时补偿和时钟调整时常用DLL。
To avoid this error, you can turn on Enable physical output clock parameters and manually configure the PLL such that the frequency is legal for both refclk inputs. Switchover Mode Automatic Specifies the switchover mode for design application. The IP Switchover, supports three switchover modes:...
For board level test, the MR/OE pin allows a user to force the outputs into high impedance. For system debug, the PI6C2952’s PLL can be bypassed. When forced to a logic HIGH, the PL_LEN input routes the signal on the RefClk input around the PLL directly to the internal dividers. ...
Analog Bits’ PCIe Gen3 SSCG PLL addresses stringent performance requirements in high-speed serial link applications that support the PCI Express Gen3 serial bus standard where SRIS (Separate RefClk Independent Spread-Spectrum clock generation) is required. This SSCG PLL is designed for digital logic...
refclk (w_JesdDevClk [genvar_JESD]), // 250MHz input .locked (w_JesdCorePllLocked_375 [genvar_JESD]), // output .outclk_0 (w_LinkClk_375 [genvar_JESD]) // 375MHz output JESD TX 3GSPS ); assign w_JesdLinkClk_RX[genvar_JESD] = ((JESD_L ==...
.rx_cdr_refclk0 (gx_644M_clk), // not using cdc fifo TODO : remove .tx_serial_data (gx_tx_ser_data[QSFP1_CH_MSB:QSFP1_CH_LSB]), // output, width = 1, tx_serial_data.tx_serial_data .rx_serial_data (gx_rx_ser_data[QSFP1_CH_MSB:QSFP1_CH_LSB]), // input, width ...