CD4066 switch resistance.

Thread Starter

TheDag

Joined Jan 1, 2010
94
Hi.
When the IC is alone without nothing, there is still resistance between pin 1 and pin 2.
how can i disable this resistance?
its problem because its permanent switch anything Im connecting to it...

sorry for my bad english.
Thanks.
 

crutschow

Joined Mar 14, 2008
25,389
As AG stated, it it used to pass high impedance signals, not power. This means the load resistance should be much higher than the switch resistance so the signal is not significantly affected.
 

Thread Starter

TheDag

Joined Jan 1, 2010
94
But how can i set the resistance to 0 ?
I Need this for this:
i have simple 9V battery with resistor that power led.
and between the Battery - and the LED -, I have no connection, here comes the CD4066 that should close the circuit for few seconds and stop...
but its have contiuous power because this problem...
sorry my bad english again...
Please help....
 

Audioguru

Joined Dec 20, 2007
11,249
Please post your schematic showing how you power and how you turn on and turn off the CD4066.

Use an ordinary transistor with series base resistor to turn on and turn off an LED.
 

bertus

Joined Apr 5, 2008
20,750
Hello,

When you look at the datasheet, the ON resistance at 10 Volts powersupply is 180 Ohms.
This can not be made lower, as it is the typical resistance of the fets inside the 4066.

Bertus
 

Attachments

Thread Starter

TheDag

Joined Jan 1, 2010
94
i cannot get the 180 ohm down ??
what can i do in this case ?
there is another IC for thing like that ??
please help....
 

SgtWookie

Joined Jul 17, 2007
22,220
You might use a power MOSFET instead of the 4066. The source terminal would have to be connected to ground, the gate to the Q output of the 555, and the drain to the remaining connection.

What is the purpose of this circuit? How much current does the load require?

What is the purpose of the switch SW1?
 

Thread Starter

TheDag

Joined Jan 1, 2010
94
SWITCH 1 is switch that needs just a connection to power up device.
i mean, even 0.01 ohm will power up the device... for example..
 

Audioguru

Joined Dec 20, 2007
11,249
When the 555 timer output goes high to 10V it lights the LED and it turns on the CD4066.
What is the load for the CD4066?
 

Thread Starter

TheDag

Joined Jan 1, 2010
94
its need the lowest current possible to power up, its only close circuit, the voltage is already connected to the device.
 

Audioguru

Joined Dec 20, 2007
11,249
5v Input, pin 13 and pin 7 measure 3.75v...
But your schematic shows pin 7 connected to ground so how can it be +3.75V?

Where is the 5V input? Do you mean that you changed the power supply to +5V?
With a +5V power supply, a 555 has an output high voltage of +3.75V which is normal and is high enough to turn on the CD4066.

We do not know the function of your CD4066 because you do not show its switch contacts connected to anything. You also did not say what they will connect to.
 

kubeek

Joined Sep 20, 2005
5,732
sn74cb3q3125 from TI has on resistance of 5 ohms, but it is in a teeny-tiny package with 0.625mm pitch.

But I agree with others that if you posted the rest of the circuit, that is the part that needs to be switched, our help will be much more useful. Without that this is just stabbing in the dark combined with pulling answers from you.
 

Thread Starter

TheDag

Joined Jan 1, 2010
94
Look, its only a bluetooth device, its power up by switch,
so its just 2 pins that i need to short.
any ohm will power up the device, that why i need it will not have any ohm...
sorry for my bad english
 
Top