- Position of VFD can be fixed.
- It works as a guide to insert VFD lead to PCB hole.
- Protect exhaust tip
- It can hold filter
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Purpose of VFD holder
Please take the following points into the consideration for the VFD holder design.
1. Datum line is designed to the glass substrate. The front glass plate must not be used as datum plane.
2. The lead cut edge is remained at opposite side of the lead out. Normally this dimension is specified as 1.5mm Max.
3. 0.5mm stand off is recommendable to prevent the washing liquid from remaining.
4. The design that tab has a tension for VFD to absorb the tolerance is recommended.
5. To design the protection of the exhaust tip, the tolerance of the tip location and diameter, and handling should be taken into consideration. Since tipless type VFD has metal cap on the backside of the base plate, please make a hole not give stress to the metal cap for exhausting.
6. The excessive sealing paste (within the tolerance of outer dimension specification) should be considered.
7. Designing the holder to stagger lead out, PCB design can be easier for the smaller lead pitch (1.5, 1.25mm). Since every other lead tilts bisymmetry direction, the following points should be considered.
- Lead tilt angle should be minimized to avoid difficulty for inserting the leads into the holder.
- The gap between lead out portion of holder and PCB should be minimized.
- It is recommended to attach the holder to PCB first, and then insert the VFD.
8. Normally, filter is used for VFD to improve display image. There are some advantages combining the filter with the holder.
- Standardization of filters
- Assembly process improvement
- Easier for switching filter color