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[SOLVED] Simple Shift Register

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scopeprobe

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Can anyone point me to a 8 or 16 bit shift register IC (like the 74HC595) that doesn't have the latch requirement please.
 

I am just astounded. How are you going to be able to use a shift register, when don’t even know how to perform the simplest of internet searches?

Okay, here you go:
74HC164
CD4021
74HC299
etc.
 

    scopeprobe

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I am just astounded. How are you going to be able to use a shift register, when don’t even know how to perform the simplest of internet searches?

Okay, here you go:
74HC164
CD4021
74HC299
etc.
Many Thanks the 74HCT164 is exactly what i was looking for. I did search but the IC's coming up all had secondary latch registers and such like which isn't what i wanted. Sometimes its just easier to ask as i knew they are very commonly used, using them isn't an issue.
 

You need this onchip with a processor or just stand alone ? How many bits total do you
need, just the 8 or are you cascading a few ?


Regards, Dana.
 

Hi,

just a bit about correct terminology:

You talk about "latch". A latch has a data input and a control input. The control input decides whether the latch is in transparent mode (inactive) or freezes the data. The latch control input is level sensitive.
If you don´t need the latch function, simply tie the control input to "transparent" state.

But the HC595 has a "D-Type flip flop". The control input is edge triggered, thus it needs "edges" to transmit the data to the output. There is no "transparent" mode on D-FFs.

Using latch or D-FF on shift registers makes sense. If you don´t use them, then you see the data rippeling through the shift registers. Usually you don´t want this.

Klaus
 

Hi,

just a bit about correct terminology:

You talk about "latch". A latch has a data input and a control input. The control input decides whether the latch is in transparent mode (inactive) or freezes the data. The latch control input is level sensitive.
If you don´t need the latch function, simply tie the control input to "transparent" state.

But the HC595 has a "D-Type flip flop". The control input is edge triggered, thus it needs "edges" to transmit the data to the output. There is no "transparent" mode on D-FFs.

Using latch or D-FF on shift registers makes sense. If you don´t use them, then you see the data rippeling through the shift registers. Usually you don´t want this.

Klaus

Yes i didn't want the latch storage capability of the 595, i just wanted just a simple shift register that i cold clock some bits for a very simple timer.
--- Updated ---

You need this onchip with a processor or just stand alone ? How many bits total do you
need, just the 8 or are you cascading a few ?


Regards, Dana.
Its just standalond driven by a clock. The 74HC164 met the requirement thanks
 

Hi,
Yes i didn't want the latch storage capability of the 595
Again: The 595 does not include a latch, it includes a D-FF instead.
Maybe you don´t care about the correct terminology, but on an (international) forum this may cause misunderstandings. Indeed every time you discuss technical informations with other people.

Klaus
 

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