October 30, 2023
NXP PMBT2369 - supercomputer NPN BJT : weekend die-shot
This is how peak compute looked like in 1960's: PMBT2369 is a successor of 2N709, heart of CDC 6600 supercomputer from 1964. I was long fascinated by transistor computers, and deep dive by Tim was extremely interesting. Key to success here is not just multi-finger layout (which is quite common in high-frequency transistors) but also gold doping which dramatically reduce saturation recovery time without any additional circuitry. You can also see this Gold trick in Fast Recovery Diodes.If you know other widely available yet inexpensive fast transistor for logic circuits - please let us know!
Die size 299x239 µm. That's probably the first transistor we've seen where there is small test BJT in every BJT.
October 1, 2023
AMD AM685DL - analog voltage comparator : weekend die-shot
Another high-performance chip from AMD: AM685 - analog voltage comparator with 6.5ns propagation time and 3ns latch setup time.Die size 1319x767 µm.
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September 1, 2023
Motorola MC14490 - CMOS button debouncer : weekend die-shot
Motorola MC14490 is a Hex Contact Bounce Eliminator, made back in 1984. Generates a clean digital signal four clock periods after the input has stabilized.Die size 2400x2048 µm.
June 1, 2023
TimesVano G170DM - transient overvoltage protection : weekend die-shot
TimesVano G170DM can be found in wired phone line protection circuit. Can survive 350A current for 2µs, clamps both positive and negative voltage spikes.Die size 3148x2292 µm.
May 29, 2023
TL432 - Shunt voltage reference : weekend die-shot
Manufacturer currently unknown. Difference between TL432 and TL431 is pinout.Die size 810x662 µm.
May 1, 2023
RCA CD4035A - CMOS Shift Register : weekend die-shot
RCA CD4035A is a CMOS 4-Stage Parallel in / out Shift Register.Die size 1733x1804 µm.
March 6, 2023
Zeptolab upgrade - March 2023
Thanks to the support of Zeptobars patrons - several vital hardware upgrades finally happened which will increase image quality and will make work more streamlined : custom wavelength RGB illuminator and 2-axis goniometer. Finally, we've also got Mastodon - @zeptobars@techhub.social - let's keep in touch there (just in case).More details below:
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