Why is the clock input pin in flip flops referred to as CP? Is there a reason to avoid referring to it as CLK?
Link to example datasheet: https://www.mouser.com/datasheet/2/916/74LVC1G175_Q100-1480587.pdf
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\$\begingroup\$ Yeah, please show an example. I don't remember I noticed such a difference before. \$\endgroup\$– Rohat KılıçCommented Jul 30 at 11:36
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1\$\begingroup\$ I have seen CP used. I have also seen CLK and CK. It depended on the manufacturer. \$\endgroup\$– Peter SmithCommented Jul 30 at 11:39
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2\$\begingroup\$ I'm not sure at all, but for decades I've assumed the P was for "pulse". Never even questioned it! Funny how a fresh mind can shed light on assumptions. \$\endgroup\$– Simon FitchCommented Jul 30 at 12:38
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The datasheet you provided is for a positive-edge triggered flip flop. This means that the flop captures the data input on the positive edge of the clock input. Perhaps the P in CP refers to positive (as opposed to negative). This is an educated guess since the datasheet does not explicitly state this, nor do I see any elaboration on the Nexperia site.
There is no standard for naming flop signals. But, I agree, CK, CLK, CLOCK are more common names.
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5\$\begingroup\$ CP is usually an abbreviation of Clock Pulse. \$\endgroup\$ Commented Jul 30 at 11:53
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\$\begingroup\$ @PeterSmith: That is very likely. Can you cite a reference? \$\endgroup\$– toolicCommented Jul 30 at 11:54
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2\$\begingroup\$ From the datasheet: Information on the data input is transferred to the Q output on the LOW-to-HIGH transition of the clock pulse. \$\endgroup\$ Commented Jul 30 at 12:26
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\$\begingroup\$ "Perhaps the P in CP refers to positive" - that would imply the use of "CN" for devices clocked on the negative edge, and I can't recall ever seeing that, anywhere. \$\endgroup\$– FinbarrCommented Jul 30 at 13:06
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\$\begingroup\$ @Finbarr: I see CN in standard cell libraries. \$\endgroup\$– toolicCommented Jul 30 at 13:08