Comimark 32.768 KHz Crystal Oscillator (Model LY590) Instruction Manual

1. Introduction

This manual provides essential information for the proper use and understanding of the Comimark 32.768 KHz Crystal Oscillator, Model LY590. This component is designed to generate a precise frequency signal, crucial for various electronic applications requiring accurate timing.

2. Product Overview

The Comimark 32.768 KHz Crystal Oscillator is a passive electronic component that utilizes the piezoelectric effect of a vibrating crystal to create an electrical signal with a very precise frequency. This specific model operates at 32.768 KHz, a standard frequency often used in real-time clock (RTC) circuits and other timing applications due to its divisibility by powers of two (2^15 = 32768), making it ideal for binary counters.

Each oscillator features a cylindrical metal casing with two leads for through-hole mounting. The compact design (2 x 6 mm) allows for integration into various circuit board layouts.

Figure 2.1: Main product image showing a single crystal oscillator and a pack of 30 units.

3. Specifications

Figure 3.1: A close-up view of a single crystal oscillator, highlighting its compact size and cylindrical form factor.

4. Setup and Installation

Crystal oscillators are passive components that require an external oscillating circuit (often an inverter gate or a dedicated oscillator IC) to function. Proper installation is crucial for stable operation.

4.1. Circuit Design Considerations

• Load Capacitance: The specified load capacitance (12.5PF) is critical. Ensure your oscillator circuit includes capacitors that, when combined with stray capacitance, match this value for optimal frequency accuracy.
• Series Resistor: A series resistor may be required to limit the crystal drive level and prevent damage or premature aging. Consult the datasheet of your chosen oscillator IC for recommended values.
• Placement: Place the crystal oscillator as close as possible to the oscillator IC to minimize trace lengths and reduce parasitic capacitance and noise pickup.
• Grounding: Ensure proper grounding of the oscillator circuit to maintain signal integrity.

4.2. Physical Installation (Through-Hole)

1. Identify Pins: The crystal oscillator has two leads. These are typically interchangeable, but always refer to your circuit diagram.
2. Insert into PCB: Carefully insert the leads into the designated holes on your Printed Circuit Board (PCB).
3. Solder: Solder the leads to the PCB pads. Use appropriate soldering techniques to avoid overheating the component. Excessive heat can damage the internal crystal structure.
4. Clean: After soldering, clean any flux residue from the board.

Figure 4.1: Illustrative image of a crystal oscillator being positioned for installation on a circuit board.

5. Operating Principles

A crystal oscillator operates based on the piezoelectric effect, where mechanical stress applied to a crystal generates an electrical voltage, and conversely, an applied voltage causes mechanical deformation. When placed in an appropriate electronic circuit, the crystal vibrates at a very stable resonant frequency. This mechanical vibration is converted into an electrical signal, providing a highly accurate and stable clock signal for microcontrollers, real-time clocks, and other digital circuits.

The 32.768 KHz frequency is particularly common for real-time clock applications because it can be easily divided down to 1 Hz (one pulse per second) using a 15-stage binary counter (2^15 = 32768).

6. Maintenance

Crystal oscillators are generally robust and require minimal maintenance once properly installed. However, adhering to best practices can prolong their lifespan and ensure continued accuracy:

• Environmental Conditions: Avoid exposing the components to extreme temperatures, high humidity, or corrosive environments.
• Physical Stress: Do not subject the crystal oscillators to excessive mechanical shock or vibration, as this can damage the internal crystal structure.
• Cleaning: If cleaning is necessary, use isopropyl alcohol and a soft brush. Ensure the circuit is powered off and completely dry before re-energizing.
• Storage: Store unused oscillators in their original packaging or in an anti-static bag in a dry, cool environment to prevent damage from static discharge or environmental factors.

7. Troubleshooting

If the crystal oscillator circuit is not functioning as expected, consider the following troubleshooting steps:

• No Oscillation:
  • Verify power supply to the oscillator IC.
  • Check soldering joints for cold joints or bridges.
  • Ensure correct load capacitance values are used.
  • Inspect the crystal for physical damage.
  • Confirm the oscillator IC is correctly wired and functional.
• Incorrect Frequency:
  • Measure the output frequency with an oscilloscope or frequency counter.
  • Recheck load capacitance values. Deviations can shift the frequency.
  • Ensure the crystal is operating within its specified temperature range.
  • Verify the crystal is the correct frequency for the application.
• Intermittent Operation:
  • Check for loose connections or poor soldering.
  • Examine the PCB for cracks or damage.
  • Ensure stable power supply.

8. Safety Information

When working with electronic components, always observe the following safety precautions:

• Static Discharge: Electronic components are sensitive to electrostatic discharge (ESD). Always use ESD-safe practices, such as wearing an anti-static wrist strap and working on an ESD-safe mat.
• Soldering Safety: Use appropriate ventilation when soldering. Wear safety glasses to protect your eyes from solder splatter.
• Power Off: Always disconnect power from the circuit before installing, removing, or performing maintenance on components.
• Component Handling: Handle components by their bodies, not their leads, to prevent bending or damage.

9. Warranty and Support

Comimark products are manufactured to high standards. For specific warranty details or technical support, please refer to the retailer's return policy or contact Comimark customer service through their official channels. Please retain your proof of purchase for any warranty claims.