When requesting an 8 MHz, 16 MHz or 25 MHz timing component, frequency alone is not enough. Specify whether the design uses a passive crystal or a powered oscillator, then provide its complete manufacturer ordering code. Two parts with the same frequency can require different circuitry and produce different system behavior.
Identify the component type and footprint
Use the approved schematic and BOM to distinguish a resonator connected to an oscillator circuit from a powered clock source. Record the package dimensions, pad arrangement, height and any case connections. Include a drawing when a part number is incomplete or the request is based on an older board.
Epson’s oscillator product information distinguishes oscillator categories, including voltage-controlled types. Identify the precise timing function before using a manufacturer selector; a matching frequency does not resolve output format, supply or control requirements.
State the electrical acceptance criteria
For a crystal, include load capacitance, equivalent series resistance, drive limit and frequency tolerance. For an oscillator, include supply voltage, output format, load and enable behavior. In both cases, state the operating temperature range and the system’s relevant timing limits.
Allow engineering to approve alternatives against the receiving circuit. An oscillator feeding a communications interface may need a different jitter or stability budget from a simple processor clock. For crystals, confirm the surrounding load capacitors and board parasitics before accepting another specification as equivalent.
Align sourcing with production verification
Separate sample requirements from the production quantity and give a required arrival date. Ask the quotation to identify the full frequency code, tolerance option, packaging and lot information. Avoid ordering against a shortened description such as “16 MHz SMD crystal” when the assembly drawing contains additional requirements.
Check startup and frequency on the target board under representative supply and temperature conditions. Use a measurement method that does not significantly load the oscillator circuit. Retain the test record and approved external component values so purchasing can distinguish a qualified alternate from an untested candidate.
Frequently asked questions
Can the same frequency part be used across different boards?
Possibly, but verify each board’s load, drive, supply and clock-input requirements. Frequency is one parameter in a complete timing specification.
Is a smaller package an automatic sourcing improvement?
No. The footprint, electrical characteristics and assembly process must suit the design. A smaller body may require a board change and a new startup-margin review.
Send SENICO a timing-component RFQ with the exact part number, frequency and quantity. Availability, variant details, price and delivery timing require quotation confirmation.