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1. Logic Elements and Logic Array Blocks in Intel® Cyclone® 10 LP Devices
2. Embedded Memory Blocks in Intel® Cyclone® 10 LP Devices
3. Embedded Multipliers in Intel® Cyclone® 10 LP Devices
4. Clock Networks and PLLs in Intel® Cyclone® 10 LP Devices
5. I/O and High Speed I/O in Intel® Cyclone® 10 LP Devices
6. Configuration and Remote System Upgrades
7. SEU Mitigation in Intel® Cyclone® 10 LP Devices
8. JTAG Boundary-Scan Testing for Intel® Cyclone® 10 LP Devices
9. Power Management in Intel® Cyclone® 10 LP Devices
2.1. Embedded Memory Capacity
2.2. Intel® Cyclone® 10 LP Embedded Memory General Features
2.3. Intel® Cyclone® 10 LP Embedded Memory Operation Modes
2.4. Intel® Cyclone® 10 LP Embedded Memory Clock Modes
2.5. Intel® Cyclone® 10 LP Embedded Memory Configurations
2.6. Intel® Cyclone® 10 LP Embedded Memory Design Consideration
2.7. Embedded Memory Blocks in Intel® Cyclone® 10 LP Devices Revision History
4.2.1. PLL Features
4.2.2. PLL Architecture
4.2.3. External Clock Outputs
4.2.4. Clock Feedback Modes
4.2.5. Clock Multiplication and Division
4.2.6. Post-Scale Counter Cascading
4.2.7. Programmable Duty Cycle
4.2.8. PLL Control Signals
4.2.9. Clock Switchover
4.2.10. Programmable Bandwidth
4.2.11. Programmable Phase Shift
4.2.12. PLL Cascading
4.2.13. PLL Reconfiguration
4.2.14. Spread-Spectrum Clocking
5.1. Intel® Cyclone® 10 LP I/O Standards Support
5.2. I/O Resources in Intel® Cyclone® 10 LP Devices
5.3. Intel FPGA I/O IP Cores for Intel® Cyclone® 10 LP Devices
5.4. Intel® Cyclone® 10 LP I/O Elements
5.5. Intel® Cyclone® 10 LP Clock Pins Input Support
5.6. Programmable IOE Features in Intel® Cyclone® 10 LP Devices
5.7. I/O Standards Termination
5.8. Intel® Cyclone® 10 LP High-Speed Differential I/Os and SERDES
5.9. Using the I/Os and High Speed I/Os in Intel® Cyclone® 10 LP Devices
5.10. I/O and High Speed I/O in Intel® Cyclone® 10 LP Devices Revision History
5.8.2.1. LVDS I/O Standard in Intel® Cyclone® 10 LP Devices
5.8.2.2. Bus LVDS I/O Standard in Intel® Cyclone® 10 LP Devices
5.8.2.3. RSDS, Mini-LVDS, and PPDS I/O Standard in Intel® Cyclone® 10 LP Devices
5.8.2.4. LVPECL I/O Standard in Intel® Cyclone® 10 LP Devices
5.8.2.5. Differential SSTL I/O Standard in Intel® Cyclone® 10 LP Devices
5.8.2.6. Differential HSTL I/O Standard in Intel® Cyclone® 10 LP Devices
5.9.1. Guideline: Validate Your Pin Placement
5.9.2. Guideline: Check for Illegal Pad Placements
5.9.3. Guideline: Voltage-Referenced I/O Standards Restriction
5.9.4. Guideline: Simultaneous Usage of Multiple I/O Standards
5.9.5. Guideline: LVTTL or LVCMOS Inputs in Intel® Cyclone® 10 LP Devices
5.9.6. Guideline: Differential Pad Placement
5.9.7. Guideline: Board Design for Signal Quality
6.1.4.1. Configuring Intel® Cyclone® 10 LP Devices with the JRunner Software Driver
6.1.4.2. Configuring Intel® Cyclone® 10 LP Devices with Jam STAPL
6.1.4.3. JTAG Single-Device Configuration
6.1.4.4. JTAG Multi-Device Configuration
6.1.4.5. Combining JTAG and AS Configuration Schemes
6.1.4.6. Programming Serial Configuration Devices In-System with the JTAG Interface
6.1.4.7. JTAG Instructions
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4.2.9.4. Guidelines
Use the following guidelines to design with clock switchover in PLLs:
- Clock loss detection and automatic clock switchover require the inclk0 and inclk1 frequencies be within 20% of each other. Failing to meet this requirement causes the clkbad0 and clkbad1 signals to function improperly. When using manual clock switchover, the difference between inclk0 and inclk1 can be more than 20%. However, differences between the two clock sources (frequency, phase, or both) can cause the PLL to lose lock. Resetting the PLL ensures that the correct phase relationships are maintained between the input and output clocks.
- Both inclk0 and inclk1 must be running when the clkswitch signal goes high to start the manual clock switchover event. Failing to meet this requirement causes the clock switchover to malfunction.
- Applications that require a clock switchover feature and a small frequency drift must use a low-bandwidth PLL. When referencing input clock changes, the low-bandwidth PLL reacts slower than a high-bandwidth PLL. When the switchover happens, the low-bandwidth PLL propagates the stopping of the clock to the output slower than the high-bandwidth PLL. The low-bandwidth PLL filters out jitter on the reference clock. However, the low-bandwidth PLL also increases lock time.
- After a switchover occurs, there may be a finite resynchronization period for the PLL to lock onto a new clock. The exact amount of time it takes for the PLL to re-lock is dependent on the PLL configuration.
- If the phase relationship between the input clock to the PLL and output clock from the PLL is important in your design, assert areset for 10 ns after performing a clock switchover. Wait for the locked signal (or gated lock) to go high before re-enabling the output clocks from the PLL.
- Disable the system during switchover if the system is not tolerant to frequency variations during the PLL resynchronization period. You can use the clkbad0 and clkbad1 status signals to turn off the PFD (pfdena = 0) so the VCO maintains its last frequency. You can also use the switchover state machine to switch over to then secondary clock. Upon enabling the PFD, output clock enable signals (clkena) can disable clock outputs during the switchover and resynchronization period. After the lock indication is stable, the system can re-enable the output clock or clocks.
- The VCO frequency gradually decreases when the primary clock is lost and then increases as the VCO locks on to the secondary clock, as shown in the following figure. After the VCO locks on to the secondary clock, some overshoot can occur (an over-frequency condition) in the VCO frequency.
Figure 52. VCO Switchover Operating Frequency