quick turn pcb assembly

SMT PCB assembly Requirements

Documentation Requirements (electronic)

The following information is required for all component purchasing / receiving / verification / inspection / programming the pick & place equipment and PCB assembly work instructions creation.

  • BOM
    • Component Description
    • Quantity
    • Reference Designator
    • Manufacturer Part Numbers
    • Indicate any “no load / do not install” (DNI) locations.
    • If you are supplying components, please identify as “Customer supplied”
  • CPL
    • Reference designator
    • X / Y – Centroid location (mils / in)
    • Rotation
    • Layer / Board side / (top / bottom – component mounting not silkscreen)
  • Redline drawing for conformal coating
  • Gerber files
  • Assembly Drawings
    • Component layout (top / bottom), polarity marking, special assembly instructions or any components that require special handling or processing, some examples may include
    • Non- washable (Moisture sensitive) components – switches, sensors, modules
    • Special prep / specific height / placement requirements
    • Lead length / trim – make sure to include +/- tolerances
    • Rework wires (pin to pin routing)
    • Component mounting (top /bottom – opposite of silkscreen – polarity)
    • Adhesives
    • Labeling / Serialization – (format / location / type)

CAM Specific PCB Assembly Requirements

Please note that we require the following information to complete the pcb assembly process, or you job will be delayed at your expense. (Note 1: Our CAM team must be notified up front that if this information is not received, the job cannot be assigned to the production floor).

  • The customer must provide us with PCB Silk Screen polarity mark information on all polarized parts (cathode, anode, pin number and what the dot or plus sign indicate.

  • Polarized components are Capacitors, Connectors, Diodes, LED’s, IC’s, Switches, Antennas, Filters, Modules, Crystals, Oscillators, Battery Clips, and Transformers).
  • Polarity marks indicate the following:
    * DOT: A "Dot (0)" on or near a lead does not represent anything unless the meaning of the dot is clarified as being a "Cathode", "Anode" or a "Pin Number Indicator".
    * + (Plus): The (+) Plus symbol on or near a lead does not represent anything unless the meaning of the dot is clarified as being a "Cathode", "Anode" or a "Pin Number Indicator".
    * K: The "K" symbol indicates the "Cathode".
    * A: The "A" symbol indicates the "Anode ".
    * Diode Symbol: The Diode symbol (looks like an arrow head hitting a target) should have the Anode near the components anode, and the Cathode near the components cathode.
    * 1: The number (1) indicates the "Pin 1" of the component.
    * Other Symbols: All other symbols on or near a lead must be clarified as to what it represents.
  • The Customer must provide us with special assembly instructions when required, such as: Height of components, Adhesive placement, Reflow profile for temperature sensitive components, et.
  • The customer must provide us with how they want us to handle polarity issues (DNI, Place as is, Call or Email for instructions). (Note 2: We must make it clear that if we are not provided this information, their job will be delayed or shipped without the parts in question. In doing this, we place the responsibility on the customer when their assembly issues, and any rework will need to be paid for by them. Our sales team, website, or the CAM team can provide customers with the checklist via email when they go over CPL, Files, and Technical Question inquiries).
  • The customer must provide the CAM team with all drawings needed to complete the surface mount PCB assembly process.

Customer Supplied / Consignment - Component Requirements

Lead time will be impacted if proper attrition is not supplied. We will always work with our customers when it comes to customer supplied components; the following is our standard guidelines. If you have expensive or a minimum quantity of any component on hand please contact the assembly sales team for details.

  • Each component must be individually packaged, labeled with BOM line item number / customer part number and/ or manufacturers’ part number.
  • The following are acceptable packages of consignment / customer supplied components (Bulk SMT not acceptable):

    • SMT Reels
    • Cut tape
    • Thru-Hole bulk or tape
    • Tubes / Trays
    • Digi-Key Reels
Package Minimum Base Minimum Overage
0201 200 100
0402 100 50
0603 50 30
SMT Diode 30 15
SMT IC 30 15
FP 20 5
LL 20 5
BGA 10 5
TH 5 2

SMT electronic components, not supplied on reels, are required to be on one continuous strip of tape. Resistors, Capacitors, Diodes (0603, 0805, 1206, 2225, SOT, SOD, MELF – packages) require a minimum of 50 pcs and/or has to exceed the required quantity by 30 pcs. (Example: build req. 40 pcs – we will require 70 pcs – this meets our minimum required 50 pcs plus 30 pcs above build requirement) Resistors, Capacitors, Diodes (0201, 0402, mini-melf, miniature packages) require a minimum of 100 pcs and/or has to exceed the required quantity by 50 pcs. (Example: build req. 80 – we will require 130 – this meets our minimum required 100 pcs plus 50 pcs above build requirement).

An overview of the PCB Assembly Manufacturing can be found here:  Turnkey pcb assembly 

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