LMK03318: What is the I2C Clock Rate spec?

Hiroyuki IRIKURA

Part Number: LMK03318
Other Parts Discussed in Thread: USB2ANY

Hello, support team.

I have a question.
Whad do you mean min of I2C Clock Rate is 100kHz and max. is 400kHz?

Refer see below LMK03318 datasheet, please.
https://www.ti.com/document-viewer/LMK03318/datasheet/i2c-compatible-interface-characteristics-sda-scl-snas6699065#SNAS6699065

This is NXP Semiconductors's official I2C specification.

UM10204 I2C-bus specification and user manual

In this I2C specification, it says below definition.

Standard-mode (Sm), with a bit rate up to 100 kbit/s
Fast-mode (Fm), with a bit rate up to 400 kbit/s

Do you mean LMK03318 can use Standard-mode or Fast-mode?

Concretely speaking, is the clock rate 99kHz OK or NG?
If 99kHz is NG, I use the I2C Clock Rate should be 100kHz over, for example 110kHz.

Thanks.

over 2 years ago

0 Evan Su over 2 years ago

TI__Mastermind 18950 points

Hi Hiroyuki,

I understand this to mean that 99 kHz would not work, but 110 kHz would be fine. I do not currently have a method to have a direct I2C connection with the LMK03318 without going through an intermediate USB2ANY controller so I can't check this experimentally. Another team member has been assigned to this thread to confirm it when they are available.

Thanks,

Evan Su

0 Kadeem Samuel over 2 years ago in reply to Evan Su

TI__Mastermind 22600 points

Hiroyuki-san,

So long as the below conditions are met, there should not be an issue. 100 kHz and 400 kHz are standard I2C frequencies, but these values are not required to be exactly met.

Thanks,

Kadeem

+1 Hiroyuki IRIKURA over 2 years ago in reply to Kadeem Samuel

Prodigy 40 points

Hello, Kadeem-san

I am relieved that the I2C Clock Rate does not need to be strictly observed.

I missed the statement on the data sheet below.

https://www.ti.com/document-viewer/LMK03318/datasheet/i2c-serial-interface-snas6694675#SNAS6694675

chap 10.5.1 also says that

"The I²C port on the LMK03318 works as a slave device and supports both the 100 kHz standard mode and 400 kHz fast-mode operations."

Thanks,

Hiroyuki

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LMK03318: What is the I2C Clock Rate spec?