Visible to Intel only — GUID: cfk1551317554896
Ixiasoft
Visible to Intel only — GUID: cfk1551317554896
Ixiasoft
4.5.2. IOPLL Parameter Values for External PLL Mode
The following examples show the clocking requirements to generate output clocks for LVDS SERDES IP using the IOPLL IP. The examples set the phase shift with the assumption that the clock and data are edge aligned at the pins of the device.
Parameter | outclk0 (Connects as lvds_clk[1:0] to the ext_lvds_clk[1:0] ports of LVDS SERDES IP transmitter or receiver) |
outclk1 (Connects as loaden[1:0] to the ext_loaden[1:0] ports of LVDS SERDES IP transmitter or receiver) |
outclk4 (Used as the core clock for the parallel data registers for both transmitter and receiver, and connects to the ext_coreclock port of LVDS SERDES IP core) |
---|---|---|---|
Frequency | data rate |
data rate/serialization factor |
data rate/serialization factor |
Phase shift | 180° |
[(deserialization factor – 1)/deserialization factor] x 360° |
180/serialization factor (outclk0 phase shift divided by the serialization factor) |
Duty cycle | 50% |
100/serialization factor | 50% |
The calculations for phase shift, using the RSKM equation, assume that the input clock and serial data are edge aligned. Introducing a phase shift of 180° to sampling clock (outclk0) ensures that the input data is center-aligned with respect to the outclk0, as shown in the following figure.
Parameter | outclk0 (Connects as lvds_clk[1:0] to the ext_lvds_clk[1:0] ports of LVDS SERDES IP transmitter or receiver) |
outclk1 (Connects as loaden[1:0] to the ext_loaden[1:0] ports of LVDS SERDES IP transmitter or receiver) Not required for the soft-CDR receiver. |
outclk4 (Used as the core clock for the parallel data registers for both transmitter and receiver, and connects to the ext_coreclock port of LVDS SERDES IP) |
VCO Frequency (Connects as phout[7:0] to the ext_vcoph[7:0] port of LVDS SERDES IP) |
---|---|---|---|---|
Frequency | data rate |
data rate/serialization factor |
data rate/serialization factor |
data rate |
Phase shift | 180° |
[(deserialization factor - 1)/deserialization factor] x 360° |
180/serialization factor (outclk0 phase shift divided by the serialization factor) |
— |
Duty cycle | 50% |
100/serialization factor | 50% |
— |
Parameter | outclk0 (Connects as lvds_clk[1:0] to the ext_lvds_clk[1:0] ports of LVDS SERDES IP receiver) |
outclk1 (Connects as loaden[1:0] to the ext_loaden[1:0] ports of LVDS SERDES IP receiver) Not required for the soft-CDR receiver. |
outclk4 (Used as the core clock for the parallel data registers for both transmitter and receiver, and connects to the ext_coreclock port of LVDS SERDES IP) |
VCO Frequency (Connects as phout[7:0] to the ext_vcoph[7:0] ports of LVDS SERDES IP) |
---|---|---|---|---|
outclk2 (Connects as lvds_clk[1:0] to the ext_lvds_clk[1:0] ports of LVDS SERDES IP transmitter) |
outclk3 (Connects as loaden[1:0] to the ext_loaden[1:0] ports of LVDS SERDES IP transmitter) |
|||
Frequency | data rate |
data rate/serialization factor |
data rate/serialization factor |
data rate |
Phase shift | 180° |
[(deserialization factor - 1)/deserialization factor] x 360° |
180/serialization factor (outclk0 phase shift divided by the serialization factor) |
— |
Duty cycle | 50% |
100/serialization factor | 50% |
— |