This document describes the electrical and mechanical specifications of the HC-49/U-S Quartz Crystal Unit produced by Aker, including frequency, temperature range, load capacitance, etc.
The HC-49/U-S is a through‑hole quartz crystal unit designed for precise frequency control in electronic circuits. This datasheet lists its key electrical parameters such as nominal frequency, load capacitance, and ESR, as well as mechanical dimensions.
Key specifications include a nominal frequency of 27 MHz, a frequency tolerance of +30 ppm at 25 °C, and an operating temperature range from –40 °C to +85 °C. Additional details cover load capacitance, shunt capacitance, drive level, and solder reflow characteristics.
| Nominal Frequency | 27.000 MHz |
|---|---|
| Mode of Oscillation | Fundamental |
| 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 Ohms Max |
| Drive Level | 100 Typ - 500 Max µW |
| Solder Reflow Characteristics | +260 °C for 10 s Max |
The nominal frequency is 27.000 MHz.
It operates from –40 °C to +85 °C (extended range).
The load capacitance is 18 pF.
The ESR is limited to 40 Ω max.