SNAA390 july   2023 LMK6C , LMK6D , LMK6H , LMK6P

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Test Standards and Test Setup
    1. 2.1 Test Standards
    2. 2.2 Test Setup in Vibration Lab
  6. 3Sinusoidal Vibration, Random Vibration, and Mechanical Shock Tests
    1. 3.1 Sinusoidal Vibration Test
      1. 3.1.1 Procedure for Sinusoidal Vibration Test
      2. 3.1.2 Results From Sinusoidal Vibration Test
    2. 3.2 Random Vibration Test
      1. 3.2.1 Procedure for Random Vibration Test
      2. 3.2.2 Results From Random Vibration Test
    3. 3.3 Mechanical Shock Test
      1. 3.3.1 Procedure for Mechanical Shock Test
      2. 3.3.2 Results From Mechanical Shock Test
  7. 4Comparison of BAW Oscillator Vibration Performance With Crystal Oscillator
    1. 4.1 Comparison Test Setup
    2. 4.2 Comparison Test Results
  8. 5Summary
  9. 6References

3.1.1 Procedure for Sinusoidal Vibration Test

LMK6x BAW Oscillator has multiple packages for differential- and single-ended outputs, see the LMK6x Low Jitter, High-Performance BAW Oscillator data sheet for more details on the BAW oscillator package options.

For this sinusoidal vibration test, the following variants were selected.

  • LVCMOS Output: DLE-4 ( 3.2 x 2.5 mm ), DLF-4 ( 2.5 x 2.0 mm )
  • Differential Output: DLE-6 ( 3.2 x 2.5 mm ), DLF-6 ( 2.5 x 2.0 mm ). BAW Oscillator has LVDS, LVPECL, HCSL output types. LVPECL output type oscillator is selected for this test.

The following are the steps involved in setting up the DUT (Device Under Test) board on the vibration fixture and for conducting the sinusoidal vibration test.

  • Parts are soldered down on the LMK6x evaluation module (EVM) and bolted to the mating plate, which is connected to the vibration stand.
  • The Keysight E3631A bench-top power supply is setup to supply 3.3 V for the EVM module.
  • For differential outputs (DLE-6 and DLF-6 package devices), LVPECL output termination is provided on the EVM. A TC1-1-13MA+ surface mount RF transformer is used to convert the differential output to a single-ended output and the output is connected to a Keysight E5052B phase noise analyzer.
  • Using VibrationVIEW® Control software, the vibration frequency is programmed to 50, 100, 200, 500, 1000, 2000 Hz at 10 g acceleration setting.
  • Once the vibration machine achieves the targeted frequency and intensity, a single trigger is issued to the E5052B phase noise analyzer.
  • Phase noise data is captured using the phase noise analyzer and phase noise plots and trace data are collected for each axis of vibration (X, Y, and Z axis).
  • Using spur power (normalized mode), frequency deviation is calculated based on the following formula:
    Equation 1. f m _ d e v i a t i o n   = f m _ f r e q u e n c y × 10 6 + V i b _ s p u r _ p o w e r ( d B c / H z ) 20

    where fm_deviation is the frequency modulation deviation and fm_frequency is the frequency of vibration.

  • From frequency deviation, ppb (parts per billion) is calculated based on the following formula:
    Equation 2. p p b = 10 9 × f m _ d e v i a t i o n c a r r i e r _ f r e q u e n c y
  • The ppb value is then divided by the set g force, to calculate ppb/g.