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turretslug · 15th Sep 2019, 4:18 pm

I think that the ceramic button on the base is simply to stop the package being forced too close to the PCB (say a rigid GRP board with tight and slightly-imprecisely-placed holes) and possibly fracturing/impairing the insulating seals and resulting in die contamination, or causing excess heat/cool stress fatigue. A bit like the hairline cracks that could occur from stressing a glass-base valve's pins.

A good design shouldn't cause the 723 package to get overly warm- but a squiggly TO-5-type heatsink will do no harm, I'd fit one and have done as a hobbyist with a few in the bits drawer, rather than an OEM worried about the bottom line.

15th Sep 2019, 4:18 pm	#21
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,395	Re: Adjustable voltage 15 amp power supply I think that the ceramic button on the base is simply to stop the package being forced too close to the PCB (say a rigid GRP board with tight and slightly-imprecisely-placed holes) and possibly fracturing/impairing the insulating seals and resulting in die contamination, or causing excess heat/cool stress fatigue. A bit like the hairline cracks that could occur from stressing a glass-base valve's pins. A good design shouldn't cause the 723 package to get overly warm- but a squiggly TO-5-type heatsink will do no harm, I'd fit one and have done as a hobbyist with a few in the bits drawer, rather than an OEM worried about the bottom line.