SNAS815C December   2020  – February 2026 LMK1D1204 , LMK1D1208

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
    1. 4.1 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 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
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Fail-Safe Input and Hysteresis
      2. 8.3.2 Input Mux
    4. 8.4 Device Functional Modes
      1. 8.4.1 LVDS Output Termination
      2. 8.4.2 Input Termination
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

3 Description

The LMK1D120x clock buffer distributes one of two selectable clock inputs (IN0 and IN1) to 4 or 8 pairs of differential LVDS clock outputs (OUT0 through OUT7) with minimum skew for clock distribution. The LMK1D12xx family can accept two clock sources into an input multiplexer. The inputs can either be LVDS, LVPECL, LP-HCSL, HCSL, CML or LVCMOS.

The LMK1D12xx is specifically designed for driving 50Ω transmission lines. In case of driving the inputs in single-ended mode, the appropriate bias voltage as shown in Figure 8-6 must be applied to the unused negative input pin.

The IN_SEL pin selects the input which is routed to the outputs. If this pin is left open, the pin disables the outputs (logic low). The part supports a fail-safe function. The device further incorporates an input hysteresis which prevents random oscillation of the outputs in the absence of an input signal.

The device operates in 1.8V or 2.5V or 3.3V supply environment and is characterized from –40°C to 105°C (ambient temperature). The LMK1D12xx package variant is shown in the table below:

Package Information
PART NUMBERPACKAGE(1)PACKAGE SIZE(2)
LMK1D1204VQFN (16)3.00mm × 3.00mm
LMK1D1208VQFN (28)5.00mm × 5.00mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.
(2) The package size (length × width) is a nominal value and includes pins, where applicable.
LMK1D1204 LMK1D1208 Application ExampleApplication Example