CD4015B: SEU Immune Shift Register?

Daniel Washington

Part Number: CD4015B

Tool/software:

Hello,

I am looking for an SEU immune shift register for a space-based mission. Do you know if the CD4015B is likely to react fatally to single radiation events? In my search, I found an ESA document that lists the 4000B series of logic chips as SEU immune. However, they mentioned it was the ST Microelectronics' 4000B family. They no longer sell the part in the series I am interested in, but the CD4015B has the same base product number (4015B). Does that mean the parts are very similar/it is likely the SEU immunity would apply to this part as well? Or are the two more or less unrelated under the hood?

I also checked TI's space-rated parts and found a few rad-hard shift registers, but none were in stock. If you have another suggestion, that would be great as well!

I really appreciate any help you can provide.

Thanks!

-Daniel

over 1 year ago

0 Clemens Ladisch over 1 year ago

Guru 317370 points

CD4000 devices are very old, so it's possible that the SEU immunity comes only from the large structures. This is likely to change when the devices are modernized.

You might be able to build a shift register from flip-flops.

0 Daniel Washington over 1 year ago in reply to Clemens Ladisch

Prodigy 10 points

Hi, thanks for the response! Making one out of flip-flops is a good idea.

As for the CD4000 devices, do you have any intuition as to why larger structures would lead to SEU immunity?

+1 Clemens Ladisch over 1 year ago in reply to Daniel Washington

Guru 317370 points

Scaling Trends of Digital Single-Event Effects: A Survey of SEU and SET Parameters and Comparison With Transistor Performance (https://ieeexplore.ieee.org/document/9293266):

[…] The results show that all the examined parameters, such as the SEU critical charge, decrease with the device feature size.

0 Daniel Washington over 1 year ago in reply to Clemens Ladisch

Prodigy 10 points

Thanks! I hadn't known that. I think this will give me enough to go on!

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CD4015B: SEU Immune Shift Register?