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I've built a D-Type flip flop + Schmitt trigger to convert a momentary switch in a toggle switch using an SN74HC74N Dual D-Type Positive-Edge-Triggered Flip-Flops With Clear and Preset and a CD40106BE CMOS Hex Schmitt-Trigger Inverters and all works fine.
Anyway, I'm using two different logic components for this circuit.
The question is: is there a kind of component that integrate on a single chip all the requested features to do the same?
Yes there is. Here's a part number of one SN74HCS74.
Not bad. Couple of points worth mentioning. Make all of the nets the same colour! There is no signifigance to the colour scheme used. Also, for clarity, shove that pin 2-6 net above the VDC1 label. Must, must, must always have bypass capcaitors on IC supply pins, as close as possible to the pins. The standard is 0.1uF (AKA 100nF) ceramic. If all of the +5V supplies are the same then label them as such. Debounce the switch. It is mechanical and the contacts literally bounce several times before settling in. The simplest way is to add a capacitor to the input of U1A, say 10mS to 100mS time constant. BTW, put a scope on the switch and see the bounce. Pin 1 /CLR probably does not need Schmitt trigger input, it is an asynchronous clear. Just connect it to the RC, use 0.1uF and select R for much longer than the supply rise time. From the data sheet, the 74HC74 t-r and t-f (input rise and fall times) at 5V is 450nS max. That is far shorter than the bounce time of a switch (mS?) so a Schmitt trigger is required. I think T.I. has small single Schmitt devices.
