Quartz Crystal is generally divided SMD and plug-in (Dip) two categories:
1) Dip: The plug can be used to size and pin points. Such as full-size, also known as a rectangle or
14pin, half-size, also known as a square or 8pin. But the 14pin and 8pin are by foot median oscillator
IC's internal core. Oscillator itself is 4pin. And from a different application level to points, can be divided into OSC (general), TCXO (temperature compensation), VCXO (voltage controlled), OCXO (Constant
temperature) etc.
| HC-49U: Generally referred 49U, also known as "low-profile" |
HC-49S: Commonly known as 49S, also known as "low-profile" | |
HC-49SS: Generally referred 49SS, also known as (ultra low profile, usually 2.5mm package height) | |
Fork type (columnar crystal): In accordance with the volume fraction can be divided into 3×9, 3×8, 2×6, 1×5, 1×4, etc |
2) SMD: By size and pin to classify, pins have 4pin and 2pin points.
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