why wiced sense need a I2c expander

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cross mob
Anonymous
Not applicable

In wiced sense shematics I saw that wiced sense using LTC4313

Why do we need a I2C expander?

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1 Solution
JacobT_81
Employee
Employee
250 replies posted 100 replies posted 50 replies posted

I2C busses are limited by their picofarad load. They generally max out at about 400pf. And each sensor generally carries a load in the range of 100pf. 

This expander allows for a larger picofarad load on the bus.

Sometimes these expanders are also used as voltage level shifters on the bus.

Jacob

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JacobT_81
Employee
Employee
250 replies posted 100 replies posted 50 replies posted

I2C busses are limited by their picofarad load. They generally max out at about 400pf. And each sensor generally carries a load in the range of 100pf. 

This expander allows for a larger picofarad load on the bus.

Sometimes these expanders are also used as voltage level shifters on the bus.

Jacob