LM10011 VID logic input timing

K. Sasaki14

Guru 10200 points

Other Parts Discussed in Thread: LM10010, LM10011

There are VID input timing characteristic in datasheet P.5.

T1 and T3 are max 1us.

My customer requires this min value for interface design.

Please tell me min value of T1 and T3.

In case of LM10010, T1 and T3 min value are 1us.

over 11 years ago

0 Timothy Hegarty over 11 years ago

TI__Guru 73602 points

LM10011 6-bit mode timing is similar to that in the LM10010, you can interpret the required spec as 1us.

0 Timothy Hegarty over 11 years ago in reply to Timothy Hegarty

TI__Guru 73602 points

If it helps to think of it this way, t1 and t3 are setup times for the VIDA, VIDB, and VIDC lines for the clocking VIDS signal. This time represents the minimum time that is needed for the VIDA, B, and C signals to setup for the VIDS to correctly latch the value.

0 K. Sasaki14 over 11 years ago in reply to Timothy Hegarty

Guru 10200 points

Is it misdescription of LM10011 datasheet?

0 Timothy Hegarty over 11 years ago in reply to K. Sasaki14

TI__Guru 73602 points

This can also be explined as the maximum time needed for the VIDA/B/C signals to be stable before VIDS strobes the data.

0 K. Sasaki14 over 11 years ago in reply to Timothy Hegarty

Guru 10200 points

My customer observed the VID interface waveform of EVM GUI software.

There is no wait time on VID interface waveform of EVM GUI.

What can I think about this? Is the timing of EVM GUI wrong? Could you tell me your opinion?

I attach observed waveform.

6712.LM10011 GUI VID waveform.pdf

0 John Hutcherson over 11 years ago

TI__Prodigy 30 points

The minimum time for t1 and t3 is 0s. In other words, the timing is such that all lines can be changed at the exact same moment; however, once VIDS transitions, there is a 1us delay (for t1 and t3) until all signals are latched.

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LM10011 VID logic input timing