SNAS636C December   2013  – July 2021 LMK00338

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Differential Voltage Measurement Terminology
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Crystal Power Dissipation vs. RLIM
      2. 8.3.2 Clock Inputs
      3. 8.3.3 Clock Outputs
        1. 8.3.3.1 Reference Output
    4. 8.4 Device Functional Modes
      1. 8.4.1 VCC and VCCO Power Supplies
  9. 9 Power Supply Recommendations
    1. 9.1 Current Consumption and Power Dissipation Calculations
      1. 9.1.1 Power Dissipation Example: Worst-Case Dissipation
    2. 9.2 Power Supply Bypassing
      1. 9.2.1 Power Supply Ripple Rejection
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Management
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.2 Clock Inputs

The input clock can be selected from CLKin0/CLKin0*, CLKin1/CLKin1*, or OSCin. Clock input selection is controlled using the CLKin_SEL[1:0] inputs as shown in Table 8-1. Refer to Section 9.2.1.1 for clock input requirements. When CLKin0 or CLKin1 is selected, the crystal circuit is powered down. When OSCin is selected, the crystal oscillator circuit will start up and its clock will be distributed to all outputs. Refer to Section 9.2.1.2 for more information. Alternatively, OSCin may be driven by a single-ended clock (up to 250 MHz) instead of a crystal.

Table 8-1 Input Selection
CLKin_SEL1CLKin_SEL0SELECTED INPUT
00CLKin0, CLKin0*
01CLKin1, CLKin1*
1XOSCin

Table 8-2 shows the output logic state vs input state when either CLKin0/CLKin0* or CLKin1/CLKin1* is selected. When OSCin is selected, the output state becomes an inverted copy of the OSCin input state.

Table 8-2 CLKin Input vs Output States
STATE of
SELECTED CLKin		STATE of
ENABLED OUTPUTS
CLKinX and CLKinX*
inputs floating		Logic low
CLKinX and CLKinX*
inputs shorted together		Logic low
CLKin logic lowLogic low
CLKin logic highLogic high