COMPONENT SOURCING / PC
Passive components
A value and case size rarely describe a passive component completely. A useful enquiry includes the full manufacturer code and the characteristics that made the original part suitable for your circuit.
- Capacitors
- Resistors
- Inductors
SOURCING CHECKLIST
Details to include with your RFQ
Keep the requirements on the same enquiry. Mark unknown details for confirmation.
- 01
Value and precision
Resistance, capacitance or inductance, with units and tolerance. Include temperature coefficient or stability requirements when they affect the design.
- 02
Electrical ratings
Voltage, power or current rating, along with any application-specific ESR, impedance, ripple-current or saturation-current requirements.
- 03
Material and construction
Dielectric, resistor technology, shielding or other construction specified on the approved BOM. Avoid treating an omitted attribute as permission to change it.
- 04
Physical fit
Case size, height, lead spacing, termination and manufacturer drawing. Confirm whether size codes are metric or imperial.
- 05
Order requirements
Exact part number, quantity, tape width or packing needs, target date and any approved alternatives as separate lines.
ENGINEERING REVIEW
Keep the original requirement visible
A capacitor with the same nominal capacitance, or an inductor with the same nominal inductance, is not automatically equivalent. Engineering must assess behaviour under the intended voltage, current, frequency and temperature.
List a proposed alternative separately with its full code and approval status. Confirm the part, quantity, condition, documentation and delivery assumptions before purchasing.
Read the alternatives checklistCOMMON QUESTIONS
Before you enquire
What if the BOM contains only a value and footprint?
Ask the design owner for the missing requirements before approving a substitute. You can send the available information as an initial enquiry, clearly marking unspecified attributes.
Can a different manufacturer be considered?
Yes, when you request alternatives. Keep the original requirement visible and ask engineering to approve the complete proposed manufacturer code and specifications.