Hi team,
I would like to ask about Maximum Supply Current described in i.MX6S/DL datasheet.
In the datasheet, the following equation is written as a general equation for estimated power consumption.
Imax = N x C x V x (0.5 x F)
And datasheet says that C stands for ‘Equivalent external capacitive load’.
Could you show me what the ‘external capacitive load’ stands for?
I think the ‘external capacitive load’ means the total capacitive load connected to IO pins.
Correct?
Thanks,
Miyamoto
Solved! Go to Solution.
Hello,
You are right, the "equivalent external capacitive load" - this is capacity of external load, connected
to GPIO pin, usually ~ (2 - 5) pF. This parameter may be estimated, using IBIS file (of the external device).
Have a great day,
Yuri
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Hello,
You are right, the "equivalent external capacitive load" - this is capacity of external load, connected
to GPIO pin, usually ~ (2 - 5) pF. This parameter may be estimated, using IBIS file (of the external device).
Have a great day,
Yuri
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------
Hi Yuri,
Thanks a lot for your prompt reply.
I think the C stands for the capacitive load connected to one GPIO pin.
Assuming that the parameters as below, is the following equation correct?
N = 100
C = 2 [pF]
V = 3.3 [V]
F = 792 [MHz]
Imax = 100 x 2[pF] x 3.3[V] x (0.5 x 792[MHz]) = 261 [mA]
Thanks,
Miyamoto
I think the frequency of 792 Mhz is very high, since it is internal core frequency.
It would be better to use real frequency on the pin ; say, for Etherenet it may be 25 MHz.
Regards,
Yuri.
Hi Yuri,
Thanks a lot.
I appeared to misunderstand about F.
Thanks,
Miyamoto
Hello,
F - is typical frequency outputs / toggles on a pin during operations.
Regards,
Yuri.