[AVR] In SPI connection, what is buffer and open drain?

[fateme91]

spi ? bufer? open drain?

Hi
in spi connection . i've heard about buffer i don't know where and how should use? and what is open drain at it?

tnks

 

[horace1]

Re: spi ? bufer? open drain?

if you do a web search you will find plenty of information on SPI and other protocols, e.g. SPI and I2C
https://www.byteparadigm.com/applications/introduction-to-i2c-and-spi-protocols/

open collector and tristate enable several devices to drive a single signal
https://www.ni.com/white-paper/3544/en/

 

[fateme91]

Re: spi ? bufer? open drain?

Ok Thanks
what do u think about a circuit which uses spi? what parameters do i need? what elements?

if you do a web search you will find plenty of information on SPI and other protocols, e.g. SPI and I2C
https://www.byteparadigm.com/applications/introduction-to-i2c-and-spi-protocols/

open collector and tristate enable several devices to drive a single signal
https://www.ni.com/white-paper/3544/en/

 

[FvM]

Re: spi ? bufer? open drain?

If you are asking how to connect peripheral devices with SPI interface to a microcontroller, you won't use a buffer in a first order, just connect the SPI signals SCK, MOSI (master-out/slave-in) and MISO (reverse direction) and an individual slave select for each peripheral device. All involved outputs are usually push-pull, not open drain. Periperal data outputs (MISO) are tristated to allow parallel operation of multiple devices. See also https://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus

Buffers may be nevertheless required in special cases, e.g. as level translation between 3.3V and 5V supplied devices.