Hello

I have read multiple posts on SPI and I2C and found that SPI is faster then I2C.

I2C have only one data line, data would transfer or received on single bus where as SPI has two data buses, data would transfer on one bus and data would received on another bus

I hope this is only reason SPI is faster

 

I hope this is only reason SPI is faster

There are other factors.

SPI is a much more basic, primitive protocol than I2C as it lacks I2C's addressing feature and there are no ACKs or other flow control constructs. Essentially, SPI operates by exchanging data between two shift registers-- one in the master device, the other in the slave device.

I seem to recall seeing some SPI devices (DACs, ADCs, etc.) that will accommodate bit rates up to 50 Mb/sec.

 

Hello

I have read multiple posts on SPI and I2C and found that SPI is faster then I2C.

I2C have only one data line, data would transfer or received on single bus where as SPI has two data buses, data would transfer on one bus and data would received on another bus

I hope this is only reason SPI is faster

The two data lines operate simultaneously so there is no advantage there. The clock signal is still the clock signal. Could I2C operate faster than the specification allows? Certainly electronic devices are more advanced now then when these interfaces were originally conceived.

 

The SPI data and clock lines are driven low and high, whereas I2C lines rely on pullup resistors so the rise time is slower for I2C.

 

It is the lack of signaling between the two that makes a great difference in speed and simplicity. You can run I2C at a higher bit rate but then would it be I2C?

 

I2C lines rely on pullup resistors so the rise time is slower for I2C

compounded by the fact that the (shared) SDA wire has to turn around twice in every 9 bits, implying a guard band.