This is a specification sheet for a quartz crystal unit, including product model, frequency, temperature range, load capacitance, etc.
The HC-49/U-S quartz crystal unit from Aker is a through‑hole component designed for precise frequency control in electronic circuits. It complies with RoHS and is lead‑free, suitable for a wide range of applications.
Key specifications include a nominal frequency of 27 MHz, load capacitance of 18 pF, ESR up to 40 Ω, and operating temperature from –40 °C to +85 °C. Mechanical dimensions are provided for PCB layout, and the part meets solder reflow requirements of up to 260 °C for 10 seconds.
| Nominal Frequency | 27.000 MHz |
|---|---|
| Frequency Tolerance at 25°C | +30 |
| Frequency Stability over Temperature Range | +50 PPM Max |
| Operating Temperature Range (Extended) | -40 to +85 °C |
| Storage Temperature Range | -55 to +125 |
| Aging per Year | +3 PPM Max |
| Load Capacitance | 18 pF |
| Shunt Capacitance (Maximum) | 7 pF |
| Equivalent Series Resistance (ESR) | 40 Ω Max |
| Drive Level | 100 µW Typ – 500 µW Max |
| Solder Reflow Characteristics | +260 °C for 10 s Max |
The nominal frequency is 27.000 MHz.
The crystal requires a load capacitance of 18 pF.
It operates from –40 °C to +85 °C (extended range).
The equivalent series resistance is up to 40 Ω maximum.