Piezo dielectric microwave device that is used with the clock circuit
of an IC to set the speed of the IC. The piezo by itself is not a clock,
so it must be used with circuitry built into the IC to create the clock signal.
Quartz crystals have been used in this manner for many years,
but TOKEN offers lower cost and more rugged piezo products in piezo
, ceramic resonators
, and . The clock circuit
consists of the passive resonator, quartz or ceramic piezo, and an active amplifier that is built into the IC.
Soldering ( Reflow )
Solderings of the chip ceramic piezo devices shall conform to the soldering conditions in the
individual specifications. The chip ceramic piezo devices are designed
for "Reflow Solderings" in the reflow solderings, too high Soldering temperatures
and too large temperature gradient such as rapid heating or cooling may
cause electrical failures and mechanical damages of the devices. Following soldering conditions are recommended:
Preheating: 150 degree C for 60 sec to 120 sec.
Soldering Temperature: 220 degree C for 10 seconds max.
Peak Soldering Temperature: 240 degree C max.
1. Rosin-based and non-activated soldering flux is recommended.
2. The content of halogen in the flux shall be 0.1 wt. % or less.
Note: In case of water-soluble type or activated type soldering flux being
applied, the flux residues on the surface of PC boards, may have influences
on the reliability of the ceramic piezo device, and cause deteriorations and failures of the devices.
Operation Temperature Ranges
The ceramic piezo devices shall not be operated beyond the specified "Operating Temperature Range" in the Specifications.
Changes / Drifts in Oscillating Frequency
It shall be noted that oscillating frequencies
of the ceramic piezo devices may drift depending on different IC manufacturer
applied and capacitance values of external capacitors and the circuit design.
Piezo Devices Characteristics Precautions for Safety
In application of the piezo devices, it is recommended that equipment shall be protected by adding
a protective and/or retardant design circuit against deterioations and failures of the ceramic piezo.
The ceramic piezo device is always acompanied by suprious resonances.
Hence in the circuit, suprious oscillations or stop of oscillation may
occur depending on the circuit design (IC applied, frequency characteristics
of the IC, supply voltage etc.) and/or environmental conditions Attention
shall be paid to those abnormalities above mentioned in circuit design.
Stray capacitance and insulation resistances on printed circuit board
may cause abnormalities of the ceramic piezo device such as "higher harmonic
oscillations".or "stop of oscillations". Attention shall be paid to those
abnormalities above mentioned in circuit design.
Abnormal Mechanical Stress
Abnormal/excess mechanical stresses such as falling shocks
shall not be applied to the ceramic piezo devices in handling, to prevent
them from being damaged or craked. Dropped devices shall not be used.
Surface Mounting Consideration
In automated mounting of the chip ceramic piezo device
on printed circuit boads, any bending, expanding and pulling forces or
shocks against the chip ceramic piezo devices shall be kept minimum to
prevent them from electrical failures and mechanical damages of the devices.
Overvoltage Spikes and Electrostatic Discharges
Abnormal/excess electrical stresses such
as over voltage spikes and electrostatic discharges may cause electrical
deteriorations and failures of the ceramic piezo and affect reliability of the devices.
Post Soldering Cleaning
Application of ultrasonic cleaning is prophibited. Cleaning conditions
such as kinds of cleaning solvents, immersion time and temperatures etc.
shall be checked by experiments before production.
Operation and Storage Conditions
The ceramic piezo devices shall not be operated and/or stored under
following environmental conditions:
To be exposed directly to water or salt water.
To be exposed directly to sunlight.
Under conditions of dew formation.
Under conditions of corrosive atomosphere such as hydrogen sulfide, sulfurous acid, chlorine and ammonia.