Ecliptek Tech Talk

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Ecliptek Corporation cordially invites you to attend a

Frequency Control Technical Seminar

Presented By

Ecliptek's Vice President of Engineering,
Mr. Tom Culhane

Who Should Attend?
Design Engineers
Component Engineers
Application Engineers
Quality Engineers

  Wednesday, September 24, 2003
Lecture: 10:30 AM to 1:00 PM (Buffet Lunch Included)
Q & A Session: 1:00 PM to 1:30 PM

  Santa Clara Hilton
4949 Great America Parkway
Santa Clara, California 95054


About the Speaker:
  Thomas Culhane is the Vice President of Engineering for Ecliptek Corporation. He has a BSEE from Marquette University and has been in the frequency control industry for 17 years. If you have pre-seminar questions, please send them to

The following is a complete listing of subjects that will be covered (course materials provided):

  • Section I: Crystal Unit Product and Theory

    • Progress in time keeping
    • Quartz history
    • What is quartz? Why quartz?
    • Crystal "Q"
    • Piezoelectric effect
    • Acoustic wave resonators; SAW vs. BAW
    • BAW: modes of vibration and cuts
    • Modes of operation: AT cut crystal thickness
    • Modes of operation: BT cut crystals
    • Crystal vibration: Ideal resonator
    • Crystal drive level - Drive level dependence
    • Drive level: Crystal activity dips
    • Crystal: Mechanical equivalent
    • Crystal equivalent circuit
    • Reactance curve of a quartz crystal
    • Crystal motional capacitance (C1)
    • Crystal motional inductance (L1)
    • Crystal shunt capacitance (Co)
    • Equivalent series resistance (ESR)
    • Center frequency, Frequency tolerance
    • Frequency stability
    • Frequency versus temperature
    • Factors of frequency stability
    • Type of cut: Frequency vs temperature
    • Frequency tolerance / stability - an example
    • Crystal and oscillator aging
    • Crystal and oscillator aging specifications
    • EC Series (HC-49/U)
    • HC-49/US: AT strip resonator
    • ESR: HC-49/US vs. HC-49/UP
    • Packaging trends
    • 2 and 4 pad plastic and ceramic SMD
    • Resonance reactance curve of a quartz crystal
    • Series versus parallel resonance
    • Load capacitance versus frequency change
    • Capacitance ratio
    • How to specify a VCXO crystal
    • Crystal for clock recovery: an example
  • Section II: Oscillator and Crystal Manufacturing

    • Autoclave: growing crystals
    • Production processes: Start to Finish
  • Section III: Oscillators: Product and Theory

    • Types of oscillators
    • Stability: hierarchy of oscillators
    • Packaging trends: DIP, plastic, and SMD
    • Voltage controlled crystal oscillators (VCXO)
    • PLL Applications
    • Packaging trends: DIP and 6 pad SMD
    • TCVCXO's and TCXO compensation
    • Logic families
  • Section IV: Pierce On-Board Oscillator Design

    • Discrete oscillator vs. on-board oscillator?
    • Amplifier gain, Loop gain
    • Oscillation barkhausen criteria
    • Positive reactance oscillator: Phase shift
    • Positive reactance oscillator: ASIC
    • Amplifier characteristics
    • Measuring amplifier output impedance
    • Pierce oscillator: feedback resistor
    • Series versus parallel resonance
    • Crystal load capacitance: Gain
    • Output impedance
    • Crystal power dissipation
    • PCB layout considerations
    • Oscillator design review