YAG Resistor Trim Tips & “Rules Of Thumb”
Questech trim standard is MIL-STD-883, notice 12, method 2032 unless otherwise specified on customer drawing, purchase order or other agreement with Questech.
Plate size limitation for trim: 5 inch x 5 inch
Nominal trim kerf widths:
Thick film: .0035 inch
Thin film: .0012 inch
*Depends on print design, stability, geometry and pre trim value with respect to nominal
Trim type will generally affect overall accuracy and cost:
**May be desirable for symmetry in RF applications or for power dissipation considerations.
“Active guard” trim of resistor loops is not particularly reliable and should thus be avoided.
All trims are orthogonal to X-Y axis. Call for exceptions.
Questech does not perform voltage, capacitance or active trims.
Standard reject marking is either water soluble or permanent ink as customer specifies. Rejects can be laser marked upon special request.
Trim of thick film resistors printed on dielectric (multilayer) is routinely performed.
Substrates acceptable for trim: Alumina and aluminum nitride
Questech has capability for trim of thermistors.