2 ms·
Interposers exist for every type of memory. We use them during hardware development to look at the waveforms in detail well beyond what is needed to read the b
by Aurornis 1y ago
Interposers exist for every type of memory.
We use them during hardware development to look at the waveforms in detail well beyond what is needed to read the bits.
The reason their interposer doesn't work with DDR5 is because they designed it with DDR4 as the target, not because DDR5 is impossible to snoop.
- AlotOfReading 1y agoThe mental image I'm getting from your description is a high speed o-scope probe copy-pasted 80 times, which would obviously be insane. But keysight docs show what looks like an entirely normal PCB that literally interposes the BGA with trace wires on every pin, which looks far too simple for a multi GHz signal. What do they actually look like and are there teardowns that show the analog magic?
- bobmcnamara 1y ago> The mental image I'm getting from your description is a high speed o-scope probe copy-pasted 80 times, which would obviously be insane It's a thing. It's expensive though. At some point you copy-paste scopes and trigger sync them. Edit: https://www.teledynelecroy.com/oscilloscope/oscilloscopeseries.aspx?mseries=484&capid=102&mid=506 https://www.teledynelecroy.com/oscilloscope/oscilloscopeseri...
- AlotOfReading 1y ago$157k starting price for a 4 channel is a bit rich for the kind of work I do.
- bobmcnamara 1y ago100%. I wonder if these are full sampling scopes. In the past we had Equivalent Time Sampling scope(wideband front end, fast sampling slow rate ADC, a variable delay trigger) and many buses have repeatable test patterns that let you trigger that way. They were always a fairly niche device.
- trebligdivad 1y agoThey're not snooping, they're modifying the address dynamically to cause aliasing.