DRV8830: VIH for I2C line

Hi Kawai-san,

SDA/SCL can accept 3.3V. A level shifter is not required.

Vil is considered a logic low below 0.25 x VCC. Vih is considered a logic high above 0.5 x VCC.

The typical values are the point where the switch typically occurs.

Hello Rick-san,

Thank you for your prompt reply. Looking at the electrical specification, VIH_MAX is 0.5 x VCC. So when VCC=6.0V, VIH_MAX = 3.0V.
If 3.3V is acceptable, what is the meaning of "VIH_MAX" specification ?

Best Regards,
Kawai

Hi Kawai-san,

There has been some confusion about this spec. The voltage on the inputs can be up to the maximum ratings.

The spec is intended to provide two pieces of information.

1) The device typically switches points from high to low and low to high at the typical values. This also shows some hysteresis.

2) The min Vil and max Vih show the values that the device will recognized a logic low (<= Vil min) and a logic high (>=Vih max). To make certain a logic high is accepted, the input voltage must be >= Vih max. To make certain a logic low is accepted, the input voltage must be <= Vil min. Between these values, the device may not have transitioned.

Think of the Vil spec as "Input logic-low voltage falling threshold" and the Vih spec as ""Input logic-high voltage rising threshold"

Hi Rick-san,

Thank you for the explanation.
Regarding your answer, I understood as follows. Please confirm whether my recognition is correct.

- To guarantee DRV8830 to communicate correctly, the device input requires below voltage.
  - High input : Must be higher than 0.5 x VCC. (i.e. when VCC=6V, input must be higher than 3.0V to guarantee operation.)
  - Low input : Must be lower than 0.25 x VCC. (i.e. when VCC=6V, input must be lower than 1.5V to guarantee operation.)

It seems the datasheet description is not a general way to specify the VIL/VIH spec. It is very confusing. I believe that normally, VIL spec has TYP/MAX value and VIH has MIN/TYP value specified.

Or, it is easier for me to understand if the parameter is "Input High Voltage Threshold" instead of "Input High Voltage"

Best Regards,

Kawai

Hello Rick-san,

I have one more question about VIH. What is the acceptable maximum voltage when VCC=6V supply ?

Is it only up to 3.3V or can it accept VCC voltage which is 6V ?
Test condition shows VIN=3.3V, however, absolute maximum rating is 7V. What is your recommendation ?

Best Regards,
Kawai

Hi Rick-san,

I understand.　Thank you very much for your support.

Best Regards,
Kawai