CT-161-CD Fujitsu Semiconductor America Inc, CT-161-CD Datasheet - Page 61

• Manufacturer Part Number: CT-161-CD
• Description: KIT 16LX FOR MB90F387
• Manufacturer: Fujitsu Semiconductor America Inc
• Series: F²MC-16LXr
• Type: MCUr

Specifications of CT-161-CD

• Contents: Board, Cable, CD
• For Use With/related Products: MB90F387S
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 865-1103

© Fujitsu
4.1.1
4.1.2
A piezoelectric device uses a substance that has a polarization characteristic.
Some crystals have an electrical deflection as an inherent characteristic.
characteristic is called "polarization," and the crystal having this characteristic is called a
"polarized crystal." More specifically, the polarized crystal contains polarized molecules
as shown in Figure 4.1.
In the figure, the direction of polarization is represented by the green arrow indicating the
direction from the positive (+) pole to the negative (-) pole.
As shown in Figure 4.2, a crystal sometimes has a characteristic that expands the crystal
when a voltage is applied in the direction of polarization (direction of green arrow). This
characteristic is called the piezoelectric effect. When a piezoelectric crystal is given a
voltage in the reverse direction of polarization (reverse direction of green arrow), the
crystal contracts.
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Crystalline characteristics of piezoelectric device
Piezoelectric characteristics
Expansion
Figure 4.1 Polarization of molecules and crystal
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Figure 4.2 Piezoelectric crystal
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Contraction
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This