CMOS alternative for 74LS112?

Thread Starter

electronice123

Joined Oct 10, 2008
311
I'm working on simulating a old circuit on multisim and I can't find the IC I need.

The IC is a 74LS112: Dual J-K Negative edge triggered flip flops with preset and clear

Anyone know what the CMOS 4XXX equivalent is?

Any help would be appreciated!
 

Papabravo

Joined Feb 24, 2006
12,767
I think asked this question about 40 years ago and the answer was -- there isn't an exact substitute in the CD4000 series. I think the closest match in CMOS is the 74HC112. The CD4027 is a JK flip-flop but the truth table has subtle differences.
 

WBahn

Joined Mar 31, 2012
25,068
I'm working on simulating a old circuit on multisim and I can't find the IC I need.

The IC is a 74LS112: Dual J-K Negative edge triggered flip flops with preset and clear

Anyone know what the CMOS 4XXX equivalent is?

Any help would be appreciated!
Do you need a CMOS equivalent, or does it specifically have to be a 4000-series CMOS equivalent?
 

Thread Starter

electronice123

Joined Oct 10, 2008
311
I think asked this question about 40 years ago and the answer was -- there isn't an exact substitute in the CD4000 series. I think the closest match in CMOS is the 74HC112. The CD4027 is a JK flip-flop but the truth table has subtle differences.
Wow, that is an old chip!
 

Thread Starter

electronice123

Joined Oct 10, 2008
311
Could I do the same thing if I added an inverter before and after the flip flop then used the 4027 since it's positive edge triggered?

Would that give me the same results?
 

ScottWang

Joined Aug 23, 2012
6,860
If the frequency is not important then other IC also can used here as 74HC04 is an inverter, 74HC14, MC14584, CD40106 are the Hex Schmitt Triggers, etc,..., it is depends on what kind of IC I have in hand.
 

Papabravo

Joined Feb 24, 2006
12,767
The 74HC112 is negative edge triggered, just like the 74LS112.
If you use the CD4027 pay attention to the "don't cares" in the truth table and observe setup and hold times.
 

WBahn

Joined Mar 31, 2012
25,068
I don't think it will...It needs to be negative edge triggered
But the 74HC112 that Papabravo recommended IS negative-edge triggered.

Get the data sheets for both the 74LS112 that you are looking to replace and the 74HC112 and compare them.

If you need it to have TTL compatible I/O, then there is the 74HCT112 to consider, as well.
 

hp1729

Joined Nov 23, 2015
2,304
I'm working on simulating a old circuit on multisim and I can't find the IC I need.

The IC is a 74LS112: Dual J-K Negative edge triggered flip flops with preset and clear

Anyone know what the CMOS 4XXX equivalent is?

Any help would be appreciated!
74ACT11112
(edited to add ...)
OOps, nope. Power in the wrong place?
 

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