Datasheet 5L1503 (IDT) - 10

link to page 10 5L1503 Datasheet
Table 7. Programmable Tuning Capacitors Parameter Bits Range Minimum (pF) Maximum (pF)
XTAL [3:0] 4 × 2 +1 / +2 / +4 / +8 pF 0 15
Figure 6. Crystal Oscillator Reference Circuit XTAL[4:0] = (XTAL CL - 7pF) × 2
(Eq.1) Equation 1 and the Programmable Tuning Capacitors table show that the parallel tuning capacitance can be set between 4.5pF to 12.5pF with a resolution of 0.25 pF. For a crystal CL= 8pF, where CL is the parallel capacity specified by the crystal vendor that sets the crystal frequency to the nominal value. Under the assumptions that the stray capacity between the crystal leads on the circuit board is zero and that no external tuning caps are placed on the crystal leads, then the internal parallel tuning capacity is equal to the load capacity presented to the crystal by the device. The internal load capacitors are true paral el-plate capacitors for ultra-linear performance. Parallel-plate capacitors were chosen to reduce the frequency shift that occurs when non-linear load capacitance interacts with load, bias, supply, and temperature changes. External non-linear crystal load capacitors should not be used for applications that are sensitive to absolute frequency requirements. ©2019 Integrated Device Technology, Inc 10 June 19, 2019 Document Outline Description Typical Applications Features Output Features Key Specifications Block Diagram Pin Assignments Figure 1. Pin Assignments for 2.0 × 2.0 mm 10-VFQFPN Package Pin Descriptions Table 1. Pin Descriptions Device Feature and Function DFC – Dynamic Frequency Control Figure 2. DFC Function Block Diagram Table 2. DFC Function Priority DFC Function Programming PPS – Proactive Power Saving Function Figure 3. PPS Function Block Diagram Figure 4. PPS Assertion/Deassertion Timing Chart PPS Function Programming Output Divider Selection Table 3. Output Divider Selection Device Output Support 5L1503 5L1503L 5L1503S OE Pin Function Table 4. OE Pin Function Table 5. OE Pin Function Summary Table 6. PD# Priority Spread Spectrum Spread Spectrum Digital Spread Spectrum Figure 5. Digital Spread Spectrum Reference Input and Selection Crystal Input (X1/X2) Table 7. Programmable Tuning Capacitors Figure 6. Crystal Oscillator Reference Circuit Absolute Maximum Ratings Table 8. Absolute Maximum Ratings Thermal Characteristics Table 9. Thermal Characteristics Recommended Operating Conditions Table 10. Recommended Operating Conditions Crystal Characteristics Table 11. Crystal Characteristics DC Electrical Characteristics Table 12. DC Electrical Characteristics – Current Table 13. DC Electrical Characteristics – Input and Output Voltage AC Electrical Characteristics Table 14. AC Timing Electrical Characteristics I2C Bus DC Characteristics Table 15. I2C Bus DC Characteristics Table 16. I2C Bus AC Characteristics Spread Spectrum Generation Specifications Table 17. Spread Spectrum Generation Specifications (5L1503S only) General I2C Interface Information How to Write How to Read Glossary of Features Table 18. Glossary of Features Package Outline Drawings Ordering Information Marking Diagrams Revision History