Datasheet PT7C4363BQ (Diodes) - 8

PT7C4363BQ Recommended Layout for Crystal Note
: The crystal, traces and crystal input pins should be isolated from RF generating signals.
Built-in Capacitors Specifications and Recommended External Capacitors Parameter Symbol Typ. Unit
Build-in capacitors X1 to GND CG 5 pF X2 to GND CD 20 pF Recommended External X1 to GND C1 20 pF capacitors X2 to GND C2 0 pF
Note
: The frequency of crystal can be optimized by external capacitor C1 and C2, for frequency=32.768Hz, C1 and C2 should meet the equation as below: Cpar + [(C1+CG)*(C2+CD)]/ [(C1+CG)+(C2+CD)] =CL Cpar is all parasitical capacitor between X1 and X2. CL is crystal’s load capacitance.
Crystal Specifications Parameter Symbol Min. Typ. Max. Unit
Nominal Frequency fO - 32.768 - kHz Series Resistance ESR - - 100 kΩ Load Capacitance CL - 12.5 - pF PT7C4363BQ
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July 2019 Document Number DS42042 Rev 1-2 8 © Diodes Incorporated Document Outline Features Description Pin Configuration Pin Description Function Block Maximum Ratings Recommended Operating Conditions DC Electrical Characteristics AC Electrical Characteristics Recommended Layout for Crystal Cpar is all parasitical capacitor between X1 and X2. Crystal Specifications Function Description Overview of Functions Registers Control and Status Register Time Counter Days of the Week Counter Calendar Counter AE W4 Communication I2C Bus Interface Overview of I2C-BUS System Configuration Starting and Stopping I2C Bus Communications Slave Address Part Marking Mechanical Information