12 MHz Crystal Oscillator
⏱️ 12 MHz Crystal Oscillator – HC-49S Package
📝 Overview
The 12 MHz Crystal Oscillator is a quartz-based timing component that provides a stable and accurate frequency reference for microcontrollers, communication circuits, USB interfaces, and timing applications. It’s commonly used with Arduino, ATmega328, STM32, and USB-to-Serial converters to maintain precise clock signals.
⚙️ Key Features
Stable frequency output: 12.000 MHz
Standard HC-49S package – through-hole type
High accuracy and low drift over temperature
Low cost and long life
Compatible with most microcontrollers and USB ICs (e.g., CH340, FT232, ATmega328)
📦 Technical Specifications
| Parameter | Value |
|---|---|
| Frequency | 12.000 MHz |
| Tolerance | ±20 ppm (typical) |
| Load Capacitance | 20 pF (standard) |
| Equivalent Series Resistance (ESR) | < 50 Ω |
| Operating Temperature | -20°C to +70°C |
| Package Type | HC-49S (through-hole) |
| Pin Spacing | ~4.88 mm (0.192 in) |
🛠️ Usage Instructions
Connect in parallel with two 22pF ceramic capacitors to GND
Connect between XTAL1 and XTAL2 pins of microcontrollers like ATmega328
No polarity — connect in either direction
For best performance, keep traces short and close to MCU
🎯 Common Applications
Arduino Uno/Nano clock (with ATmega328P)
USB-to-serial converters (CH340/FTDI)
Microcontroller timing reference
Frequency counters and timekeeping
Embedded and industrial control systems