ESD Verification: Difference between revisions

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=== HBM ESD Dissipation ===
=== HBM ESD Dissipation ===
[[File:Hbm esd dissipation SG13G2@1.2V.png|none|thumb]]
Assuming a typical ESD discharge of a few nanoseconds the energy absorbed by the chip itself is in the micro Jules range
 
That's nothing[[File:Hbm esd dissipation SG13G2@1.2V.png|none|thumb]]


=== ESD Waveforms ===
=== ESD Waveforms ===
[[File:Hbm esd waveforms SG13G2@1.2V.png|none|thumb]]
The current flowing through the pad during an ESD event is only 2100 * 1e-10 at its peak.
 
2100*0.1nA = 210nA = 0.2uA  ... high ohmic inputs when being turned off are doing high ohmic things.[[File:Hbm esd waveforms SG13G2@1.2V.png|none|thumb]]


=== HBM ESD Zoomed In ===
=== HBM ESD Zoomed In ===
Line 27: Line 31:


== The IHP SG13G2 @ 3.3V case ==
== The IHP SG13G2 @ 3.3V case ==
Lets say we ran  and get this test case for a 20mA pad cell for IHP's SG13G2 process for a voltage of 3.3V
When you look at this thing here and its simulation result, it's no surprise that it has the same results as the 1.2V one, because they've been dimensioned based on the same math.[[File:Io cell 20mA.png|none|thumb|IHP cell for 20mA @ 3.3V]]
 
Then you end up with this thing
[[File:Io cell 20mA.png|none|thumb|IHP cell for 20mA @ 3.3V]]


=== HBM ESD Dissipation ===
=== HBM ESD Dissipation ===

Revision as of 02:05, 26 May 2026

Below two examples from our automated test suite showcasing how our approach reverse solving the HBM model math as elaborated in Physics-Based_Wire_Sizing_for_I/O_Pad_Cells actually leads to simulation results in ngspice which show that our ESD diodes we chose actually protect our internal circuitry.

Oh wow. When you solve Ohm's law in one direction and then the other, you end up with the current you originally have defined at a certain voltage. Who would have thought this... anyway. Here some examples.

After running

./tests/test_all_padcells.sh visual

you end up with a folder called "generated_output"

We're looking at "generated_output/SG13G2/padcell/1.2V" and "generated_output/SG13G2/padcell/3.3V" here as examples

The IHP SG13G2 @ 1.2V case

Comparing those two you will notice that the pad with the lower operational voltage needs more area.

While at first counter intuitive, this is because we're not dealing with Ohm's law here but with solid state physics, such as hot carriers and the such.

The thermal budget also plays a role but not as much as electron migration and so.

IHP cell for 20mA @ 1.2V

HBM ESD Dissipation

Assuming a typical ESD discharge of a few nanoseconds the energy absorbed by the chip itself is in the micro Jules range

That's nothing

File:Hbm esd dissipation SG13G2@1.2V.png

ESD Waveforms

The current flowing through the pad during an ESD event is only 2100 * 1e-10 at its peak.

2100*0.1nA = 210nA = 0.2uA ... high ohmic inputs when being turned off are doing high ohmic things.

File:Hbm esd waveforms SG13G2@1.2V.png

HBM ESD Zoomed In

Hbm esd zoom SG13G2@1.2V
Hbm esd zoom SG13G2@1.2V

The IHP SG13G2 @ 3.3V case

When you look at this thing here and its simulation result, it's no surprise that it has the same results as the 1.2V one, because they've been dimensioned based on the same math.

IHP cell for 20mA @ 3.3V

HBM ESD Dissipation

File:Hbm esd dissipation SG13G2@3.3V.png

ESD Waveforms

File:Hbm esd waveforms SG13G2@3.3V.png

HBM ESD Zoomed In

File:Hbm esd zoom SG13G2@3.3V.png