1. Overview & Function

️· Product: OP4018B – A 718.864 MHz optical timing clock. This implies it's generating a precise clock signal for optical communication systems.
️· Technology: SAW (Surface Acoustic Wave) Oscillator. SAW oscillators are known for their frequency stability and precision.
️· Package: SMC-8 (Surface Mount Case - 8-Terminal). This is a compact surface-mount package designed for automated assembly.
️· Application: Primarily used in optical communication equipment where a precise and stable clock is required.

2. Key Specifications & Performance

️· Frequency: 718.864 MHz
️· Operating Voltage (VCC): 3.135 - 3.465 VDC (Nominal 3.3V)
️· Temperature Range: -40°C to +85°C
️· Tune Input Range: Customer-defined range is supported (the part itself has a range, but the customer can exploit more than that)
️· Power Consumption: Approximately 70 mA
️· Enable/Disable: Available via a dedicated Enable/Disable terminal (Pin 3).

3. Pinout & Electrical Connections

️· Pin 1 (VCC): Positive Supply Voltage
️· Pin 2 (Ground): Ground Connection
️· Pin 3 (Enable/Disable): Controls the oscillator's operation (active/inactive).
️· Pin 4 (Q Output): Main clock output signal.
️· Pin 5 (Q Output): Inverted clock output signal (complementary to Q output).
️· Pin 6 (Ground): Ground Connection
️· Pin 7: Unused
️· Pin 8 (Tune Input): Used for frequency adjustment or stabilization (customer specific).
️· LID: Ground connection – crucial for thermal and RF performance.

4. Physical Dimensions & Package Details

️· SMC-8 Package: Detailed dimensional drawings are provided (A through N) with both millimeter and inch measurements. This is vital for PCB layout and component placement.
️· Lead Finish: Not explicitly stated, but typically would be a tin or tin/lead finish for surface mount applications. (Check with RFM for the exact finish).

5. Important Considerations & Notes

️· Electrostatic Sensitive Device (ESD): Handle with appropriate ESD precautions.
️· Export Restrictions: Requires U.S. Department of Commerce approval for export.
️· RF Performance: Performance is best achieved with proper PCB layout (ground planes, controlled impedance traces), proper termination (50 ohms), and minimizing external noise.
️· Frequency Stability: SAW oscillators are inherently stable, but careful design to minimize environmental influences (temperature, vibration) is important for optimal performance.
️· Linearity The part is designed to be easily tunable beyond nominal values, enabling customer flexibility.

6. Patents

️· The design incorporates elements covered by US patents 4,616,197; 4,670,681; and 4,760,352.



In essence, the RFM OP4018B is a highly precise, surface-mount SAW oscillator designed for optical timing applications, requiring careful handling and layout for optimal RF performance.