What is the opposite of an 74HC165?

MJHanagan

Hi everyone - I am using a 74HC165 IC to read a set of 8 parallel inputs and send the result in a serial data transfer. I am now looking for the IC device that does the opposite (serial in parallel out). There is a 74HC164 that looks like its would do just this but looking at the data sheet it seems to indicate the input bits are posted to the LSB then sequentially marched towards the MSB position. I need to read all 8 bits into something like a shift register then after all 8 bits are in the entire set gets transferred to the outputs. Am I reading the data sheet right? If so is there another device that can shift the bits to the output all at once so I don't get momentary on/off signals at the outputs as the data gets transferred in?

Publison

You want a 74HC595.

http://www.parallax.com/StoreSearchResults/tabid/768/txtSearch/74HC/List/0/SortField/4/ProductID/229/Default.aspx

Data Sheet Here

You would keep OE high until you had all bits loaded. The nothing should show on the output until OE went Low.

Data Sheet Here

You would keep OE high until you had all bits loaded. The nothing should show on the output until OE went Low.

MJHanagan

Thank you!

Ron Czapala

There are also various I/O expander chips that let you set pins as a combination of inputs and outputs.

The MCP23016 and MCP23017 are I2C devices - the MCP23S17 is a SPI device.

MJHanagan

Wow, I can see how useful these expanders could be because of their versatility. Thanks for the tip!