Hi,

I was going through some article and reading that frequency will be half of data rate.So I want to know that I2C speed when we say 3.2Mbps does it means that does it means that clock frequency will be 1.6MHZ ?

Same case when I say SPI Clock have 50MHZ maximum clock frequency does it mean that data rate is 1Gbps?

I am Confused between SPI and I2C data rate and frequency. Please explain ?

Thanks

 

One cycle of the clock transfers 1-bit of information.

 

Means 3.2Mbps means 3.2MHZ clock ???

 

Context is important. The statement "frequency will be half of data rate" is true in cases such as old school RS232 serial data where there is no clock and the data is all you have.

In this case for RS232 the only signal is data and the fastest change/highest frequency is when the data is alternating bits 1 and 0, so you get a frequency will be half of data rate.

In SPI and I2C you have both a clock and data signal. Each data bit must have a full clock pulse high and low, so the clock rate is twice the data rate. Thus the clock frequency will be twice the data rate

Generally, don't go by general statements and look at each situation fresh.

 

Hi

I got it.means you want to say when I say the i2c 3.4Mbps it means I am talking about click frequency of 6.8MHZ and for spi clock 50MHZ Signal I can say clock rate will be 25Mbps.