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The high level voltage at the OUTPUT pin of the CL 555 timer model does not track the vcc supply.

This is incorrect and can be misleading.

In addition, the output voltage drop vs. current sourced or sinked does not match the 555 spec sheet well, even for Vcc = +5V.

Indeed, there is a big problem with the "internal source" in the 555. In the circuit https://www.circuitlab.com/circuit/8ymg74/555-monostable/ I provide a 12 V source and the output only goes to 5V, not close to 12 V as it should according to specs and my experiments with an LM555.

Update: it looks like CL have fixed the thresholds problem in that the upper and lower thresholds in their 555 model now track 2*VCC/3 and VCC/3 respectively.

However V(output) still does not track VCC!

The CL 555 model in my example circuit above also still does not run at VCC = 10V.

:(

Hello everyone,

It is July 2016 and I am still experiencing the same problems:

• V(output) = 5V even for Vcc = 9V.
• resetbar seems to be switching on immediately on any non-zero voltage no matter how small

The things that are working correctly now:

• The 1/3 and 2/3 threshold voltages seem to be correct now. At least my 9V circuit is functioning properly.

Is it something that is intended to be fixed? Thanks!

Still nothing... =/

Having the same issue here.

Still having this issue 9 years after it was originally reported.