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Keith956 · 23rd Feb 2021, 2:44 pm

I've only got reference manuals for the CMOS 4000B series made by Fairchild (some of which were designed in the Bristol office where I worked in the late 70's) and the RCA 4000A/B series.

4049A - the A series were the originals, the B series came later and it appears had a higher voltage rating, plus came in B (buffered) or UB (unbuffered). The idea of the buffered one was they had an output buffer which meant the output high/low resistance was independent of logic state of the inputs; the penalty was they were slower.

The books say the MIL spec parts had suffixes of D, K, F, H and E. From what I can make out D were welded-seal packages, E were plastic, F were ceramic frit-seal, K was ceramic flat-pack. H was bare chip.

The 4049A by the way was a hex inverter. If you need I can copy the datasheet for you.

23rd Feb 2021, 2:44 pm	#7
Keith956 Heptode Join Date: Jun 2019 Location: Oxfordshire Posts: 738	Re: Plastic or ceramic ICs? I've only got reference manuals for the CMOS 4000B series made by Fairchild (some of which were designed in the Bristol office where I worked in the late 70's) and the RCA 4000A/B series. 4049A - the A series were the originals, the B series came later and it appears had a higher voltage rating, plus came in B (buffered) or UB (unbuffered). The idea of the buffered one was they had an output buffer which meant the output high/low resistance was independent of logic state of the inputs; the penalty was they were slower. The books say the MIL spec parts had suffixes of D, K, F, H and E. From what I can make out D were welded-seal packages, E were plastic, F were ceramic frit-seal, K was ceramic flat-pack. H was bare chip. The 4049A by the way was a hex inverter. If you need I can copy the datasheet for you.