Rugged Quartz Crystals & Oscillators For High Shock

Applications

100,000G and more

History

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Pre 1970 – High shock was a few 100g

1970s – resonators could survive shock

levels of a few 1,000g

1980s – 10,000g (HG products)

2000s – 100,000g CX4HG and HGXO

Two basic failure mechanisms

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Dismount

Is the epoxy mount strong enough to hold

the resonator in place?

Breakage

Is the resonator design robust enough to

survive the stresses induced by high shock

events?

Keys to ruggedness

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Small size

Smaller devices typically experience lower

stresses under acceleration

Stress length2/thickness

Maintain scale, then stress size

Fixed frequency, stress (length)2

Smaller size

Lower stress

Can withstand higher accelerations (shocks)

Mechanical support

Single end mount is good

Dual end mount is better

Lower stress

thickness

lengthstress

2

Stress dual–end mounting = stress single–end mounting6

1

Avoiding dismount

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Shorten resonator

Shear dismount: Fixed frequency and bonding area, 𝐴, (mass)∝(length), so 𝐹 /𝐴∝ (length), so shorter resonator is less likely to dismount

Peel dismount: Torque τ ∝ (length) x (mass) ∝ ( length)2, so shorter resonator is less likely to dismount

The right adhesive Strong

Low outgassing

Doesn’t de-Q the resonator

Plenty of it

Dual-end mount, for AT (introduces other issues) Force distributed

Avoiding breakage

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Simple geometry (avoiding weak structures)

Fairly easy for ATs

More challenging for tuning-forks

Small resonator (Stress length2/

thickness)

Dual-end mount (reduces stress)

Where we are today

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AT crystals

Most products offer 10,000g or more

Some offer up to 100,000g

Could achieve 200,000g or more

Would pursue if there were a market

demand for this

Tuning-fork crystals

Many offer up to 5,000g

Up to 30,000g in preferred directions in some

cases

More information can be found on our

website www.iqdfrequencyproducts.com

Standing out from the crowd

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