4066 drive

[1843]

Hi all,
I want to drive 4066 from positive pulses ( -5V to 0 ). So I must use E of npn transistors.
Please tell me what resistors is needed for npn's E ( and gate of 4066 if is necessary ).
Thanks in advance

[Carl-NC]

Need a better explanation... what is the voltage range of the gate pulse? What are the supply voltages on the 4066?

[1843]

It is like Hammerhead but pulses have a positive duty cycle.
The output pulses of u-controller are -5V to 0 and supply voltages of 4066 are -5V and +5V.

[Carl-NC]

So just use the same sort of level shifter I used on HH... 10k base resistor, NPN, 10k collector resistor. You can adjust the R values per required speed and desire to reduce power.

[1843]

So just use the same sort of level shifter I used on HH... 10k base resistor, NPN, 10k collector resistor. You can adjust the R values per required speed and desire to reduce power.

The duty cycle of u-controller is not the same with 74hc221...

[1843]

So just use the same sort of level shifter I used on HH... 10k base resistor, NPN, 10k collector resistor. You can adjust the R values per required speed and desire to reduce power.

The duty cycle of u-controller ( --- ) is not the same with 74hc221 ( ... ).
It is like this:

0V.............---...........---........
-5V--------....--------....------

I must use the Emitter of npn transistors for shifting the level to -5v +5V.
If I use collector, the duty cycle acts conversely...

Please tell me resistors values for base and emitter (and gate of 4066 if is needed).

Best regards

[Carl-NC]

If you apply the 0/-5V to the base of the NPN, then the emitter will have -0.7/-5V levels. You cannot get +5 on the emitter.

One solution is to simply invert the uC pulse in software. Another solution is to add another NPN inverter to the level shifter I used in HH:

[1843]

Thank you very much!

Thank you very much!

The resistors are 10k?

Best regards

[Carl-NC]

10k should work fine.

[ivconic]

Trigger or what?

If you need trigger than use ordinary fet...You may play anyway you want with it. Look in any Tesoro schematic....

[1843]

If you need trigger than use ordinary fet...You may play anyway you want with it. Look in any Tesoro schematic....

Thank you ivconic,
I want it for sampling switch just after the first op amp...