CD4027B: CD4027B: The otput Q won't change UPDATE

Please draw a schematic.

Hey Zero,

Yes, please provide a schematic to help me visualize the set up. It may be difficult debugging without a scope.

Hi All,

schematic attached. the push button is https://www.digikey.com/product-detail/en/e-switch/RP3502ARED/EG1930-ND/280448

TOGGLE BUTTON _NEW.pdf

Currently i can't access the LAB with the scope because of COVID-19.

If you can do any suggestion without a scope, i would help very much.

I tried to add a 100k pull down on CLOCK2 pin ( OUT in my schematic) but  there is no difference. 

Best Regards,

Hi Clemens,

thank you for the tip, not it seems to work, also i will scope it once i have access to lab.

One more thing, i want to add a analog switch with enable on the Q2 of the jk flip-flop.

I want to have Q2 signal routed to my output only when the button is pressed .

I have CD4016BE, would you recommend this switch for this purpose?

i want connect Q2 to pin INA(Pin1) , my output to pin2 OUT2, and i want to drive the control pin13 with

1) the same signal as CLK signal on jk flip-flop? I want to drive with the output of the buffer, is it ok to drive with same signal the CLK of flip-flop and control of analog switch?

2) is it better to drive the control of analog switch with the un-buffered  push button?

Best Regards,

and thank you for  the help.

What should the output voltage be when the button is not pressed? Low, high, or floating?

You can use any 12 V switch for this, such as the CD4066B or TS12A4514.

If you use the unbuffered button signal, the bouncing can cause the switch to quickly close/open multiple times. This might not matter in your application, but you could just as well use the buffered signal when you already have it. (A CMOS output can easily drive many CMOS inputs.)

The output voltage on my output should be floating when the button is not pressed. I don't want it low or high thus i'm want to use the switch.

1) is the CD4016BE ok?

2) all my components are DIP and i think i will chose SMD in new PCB version ( CD4027B, CD4016B, CD4016B)

would you recommend new TI components to replace CD4027B, CD4016B and CD4016B?

Any SPST switch can be used to make the signal float. The CD4016B is such a switch.

There are 12 V switches, but you will not be able to find any logic gate running at 12 V, except in the old CD4000 family.

Hi Clemens,

thank you for the info on CD4000 family.

1) one question regarding CD4027B and CD4016B, how many current can they provide ? or do i need a buffer after the CD4027B?

2) is it reasonable to set a buffer after the CD4016B switch because i need floating output wen button not pressed ?

So if i want to use newer IC then i have to have LDO of DC-DC.

Which newer TI component would you recommend to  replace the CD4027B, CD40106B and CD4016B on lower voltages?

and for the switch i will need an external 12V signal that will i switch with 5V or 3v3 control signal?

Br.

1) CMOS input have a very high impedance. You never need a buffer to drive a device in the same family.

2) The switch I/Os are high impedance when off. A buffer would not add anything.

There are switches with TTL-compatible switching thresholds (0.8 V/2.0 V) at the control input; these work with 3.3 V and 5 V logic. There are also switches with 1.8-V-compatible control inputs.

Why do want to use newer ICs? The requirement for an additional power supply is a negative; what benefit do you want to achieve?