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Need help finding a I2C chip

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MAXPAYNE

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Is there any I2C chip available which will do the following functions as attached image ?
 

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cks3976

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Can you please elaborate ? This is a MUX, but what an I2C bus doing here ?
 

MAXPAYNE

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Suppose you send an I2C value, for that specific value, the output will be A0=0, A1=0
then you send another specific value , for that specific value, the output will be A0=0, A1=1
The output of A0 and A1 logic condition will be changed based on the I2C value at the input
 

cks3976

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Fine.. then this cannot be a simple MUX.. and also I am not sure if any COTS device exist to perform this logic. You may have to have a small programmable device with a look-up table that can output various A&B combinations on the output based on the I2C Data. You cannot use a simple MUX because the I2C clock is not a periodic signal.
 

KlausST

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Hi,

a simple I/O port could do this.
Like PCA9536DP.
Then you have two spare I/O pins.
you can control four line as I/O individually.

Klaus
 

syenidogan

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Is there any I2C chip available which will do the following functions as attached image ?

you are using 2 pins and with two pins you can do 4 state. so what is the idea using extra compenent to do the same thing ?
 

MAXPAYNE

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you are using 2 pins and with two pins you can do 4 state. so what is the idea using extra compenent to do the same thing ?

because in those two pins which will carry I2C data, there are other slave devices connected.
 

milan.rajik

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Google for I2C 4 input MUX or I2C Multiplexer.
 

paulfjujo

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a simple PORT output 8 bits
ex: PCF8754 .. use only A0 A1
i2C value => Binary value
 

Easyrider83

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Pins marked as 'A' is address pins. Port expanders using I/O pins as input and output. Here should be some misunderstanding I suppose.
 

MAXPAYNE

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I just marked them as A. They could be anything. whatever they are, all are output.
 

paulfjujo

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Pins marked as 'A' is address pins. Port expanders using I/O pins as input and output. Here should be some misunderstanding I suppose.

you are right...
i notice A0 and A1 as Output corresponding to the request .
right definition is P0 P1
because but there are also Pin A0 A1 A2 to define offest adresse of PCF8574
 

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