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
AN56 CALCULATING TOTAL OUTPUT JITTER FOR PLLS 1. Introduction Phase-locked loops (PLLs) within SONET/SDH systems are required to meet stringent jitter specifications. To ensure that the system, including the several PLLs in series, meets the output jitter requirements, it is useful to calculate...
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:...
Arria II Device Handbook Volume 1: Device Interfaces and Integration July 2012 Altera Corporation Chapter 5: Clock Networks and PLLs in Arria II Devices Clock Networks in Arria II Devices 5–15 Clock Output Connections PLLs in Arria II GX devices can drive up to 24 RCLK networks and eight ...
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 ==...
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。
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 ...
.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 ...
(internal) VCXO = 122.88 MHz CLKinX = 30.72 MHz Example 2: LOS_LAT_SEL = 0000 1000 LOS_FRQ_DBL_EN = 1 VCXO = 122.88 MHz CLKinX = 122.88 MHz CNT reset CNT reset LOS (internal) LOS detection 0.5 RefCLK Cycles LOS_LAT_SEL CLKinX STATUSx Example 3: LOS_LAT_SEL = 0000 0010 LOS_...