TDA4VE-Q1: I2C0_SCL tLOW time can't meet datasheet requirement

jinzhong HUANG

Part Number: TDA4VE-Q1
Other Parts Discussed in Thread: TDA4VL

Dear TI expert.

We use TDA4VL as our project solution and connect the I2C0 interface to PMIC(TPS6594133) directly with 2.2K pull-up resistors.

The I2C is work at fast mode(400KHz)

And according to the HW test, we found that the tLOW time can't meet the requirement from datasheet. The duty time is about 50% and that is mean when the SCL frequency is 400KHz, tLOW is equal to tHIGH which is about 1.25uS. But the datasheet just show that the MIN of tLOW is 1.3uS. How can we meet this requirement? Can we just change the duty time via setting the register?

BTW, The actual measured of tLOW value is 1.22uS.

8 months ago

0 jinzhong HUANG 8 months ago

Prodigy 120 points

TDA4VL should change to TDA4VE.

0 Miles Dodd 8 months ago in reply to jinzhong HUANG

TI__Prodigy 380 points

Hi Jinzhong,

You should be able to adjust tLOW through the I2C_SCLL register as shown below.

Best Regards,

Miles

0 jinzhong HUANG 7 months ago in reply to Miles Dodd

Prodigy 120 points

Hello Miles,

Thanks for your reply!

I have another question need to confirm with you. We use TDA4VE IIC1 as EEPROM communicate interface. Druing the HW test we found that the Fall time of the SCL signal is 11ns which is smaller than the IIC Industry Standard: 20ns - 120ns. Is this accepable? If not, how can we do to fix this issue?

Best Regards,

Jinzhong

0 Miles Dodd 7 months ago in reply to jinzhong HUANG

TI__Prodigy 380 points

Hi Jinzhong,

Can you confirm which I2C instance you are using?

Section 6.10.5.12 of the data sheet mentions that the I2C instances that use LVCMOS IO buffers will have this fall time violation. You can find whether or not an interface uses LVCMOS or the I2C Open Drain buffers in Table 5-1. Pin Attributes.

The fall time violation is not likely to cause any issues, but this is dependent on the device being communicated with. If the device is sensitive to fall time violations, are you able to change I2C interfaces to one that uses the Open Drain buffers?

Best Regards,

Miles

0 jinzhong HUANG 7 months ago in reply to Miles Dodd

Prodigy 120 points

Hello Miles,

Thanks for your reply in time!

It's LVCMOS mode. How can we do to change I2C interfaces to the Open Drain buffers?

Thanks!

Best Regards,

0 Miles Dodd 7 months ago in reply to jinzhong HUANG

TI__Prodigy 380 points

Hi Jinzhong,

The I2C interfaces that use open drain buffers are the following, WKUP_I2C0, MCU_I2C0, and I2C0. Are you able to switch to using MCU_I2C0?

More information can be found in the TRM section 5.5.18 I2C.

Best Regards,

Miles

0 jinzhong HUANG 6 months ago in reply to Miles Dodd

Prodigy 120 points

Hello Miles,

Sorry for late reply!

We are not able to change the I2C interface at this stage. So it seems that we couldn't slove this issue by configuring the registers. Thanks for your great effort!

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TDA4VE-Q1: I2C0_SCL tLOW time can't meet datasheet requirement