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I am planning to use LTC4015 IC for buck charger application. I have to interface the IC with my host MCU.

LTC4015 product page

I have other charge controller ICs connected over same I2C bus. Other ICs are stating I2C bus speed to be 100 kHz, but this LTC4015 IC's specification says 400 kHz for clock speed of I2C bus.

I wanted to confirm, is it possible to drive the LTC4015 on 100 kHz speed? If yes then great. If not, will changing the speed of I2C bus frequently causes any improper behavior in MCU? (Is it recommended?)

We are using NXP MC9S12XEP100.

MC9S12XEP100 product page

I2C specs of LTC4015

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Your snip of the datasheet is missing a very important part - the heading.

If you look up from the 400kHz you can see it's in the MAX column.

So the speed specified is simply the maximum clock rate. You should be fine at 100kHz.

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  • \$\begingroup\$ Hello mike65535, Thanks for your answer. Yes, 400KHz is maximum value for SCL. Thus there will be no need for me to change the speed of i2c bus, as all the slaves will be running on same speed. I was confused because there was no minimum speed specified in Datasheet . \$\endgroup\$
    – Mandar Sansare
    Commented Apr 27, 2018 at 12:49
  • \$\begingroup\$ Yes, sometimes there are minimum speeds specified for some signals but it's relatively rare. Reset rise/fall times are often spec'd to be faster than x. If that's all you need mark the post as "the answer". ;-) Good luck with the project. \$\endgroup\$
    – mike65535
    Commented Apr 27, 2018 at 12:59

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