How to designg a simple Dual complementary SPST CMOS with a single control

[[email protected]]

Hi,

I really need help....



I'm looking an easy way to design a dual complementaty SPST switch
with a single control line in order to replace an obsolete Tesas
Instrument IC: TL604CP



Here is the information regardind the TL604CP:


http://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=TL604&pf


The TL604 is a dual complementary SPST switch with a single control
input."
and The TL601, TL604, TL607, and TL610 are a family of monolithic
P-MOS analog
switches that provide fast switching speeds with high roff/ron ratio
and no
offset voltage. The p-channel enhancement-type MOS switches accept
analog
signals up to ±10 V and are controlled by TTL-compatible logic inputs.
The
monolithic structure is made possible by BI-MOS technology, which
combines
p-channel MOS with standard bipolar transistors. "

i.e. a TTL-controlled SPDT, analog switch implemented in PMOS channel

Could it be possible to design a such switch using a CMOS CD4066 or by
using a couple of fets?

Thanks a lot to helping me!

Mike

 

[Anders F]

Hi,

I really need help....



I'm looking an easy way to design a dual complementaty SPST switch
with a single control line in order to replace an obsolete Tesas
Instrument IC: TL604CP

Did you check maxim-ic.com and the like?

Could it be possible to design a such switch using a CMOS CD4066 or by
using a couple of fets?

Yep. Be aware of make-before-break demands though!

(for reference you should state what specs you actually need - not just what
obsolete component that satisfy them ;-)

/A

 

[[email protected]]

Yep. Be aware of make-before-break demands though!

(for reference you should state what specs you actually need - not just what
obsolete component that satisfy them ;-)

Thanks for your answer.

In fact, I have an old peavey Deuce series VT with 3 IC TL604CP
defect. What I'm looking for is an easy way to replace them. The
TL604CP is an obsolete part and to get them ... I have to order 100 of
them at $2.90 us each.

The only information that I could provide you is the supply voltage
+16 and -16 Volts. The control voltage is about 8 volts.

I'm trying to figure out how to do it ... but I'm not a specialist in
the field of circuit design.

I know that it is possible to design a simple circuit with a couple of
resistors and FET or using a CD4066.

Here is what I found:


FET1 FET2
input ---- R1---- | ----------| |----------------------- output
| | |
| ------
| | |
|- |
Vc2 ---- |
|- vc1
|
|
|
GND


This is a Jfet zero signal switch. The series jfet is connected with
its source on the buss. This is a virtual earth, so the control
voltage to the gate will effectiveley be grounded referenced.

Q1 OFF ON
Q2 ON OFF
Vout OFF ON

and:


Voltage control ---------- VC1 ----Vc1
|
|
|
----- inverter ---vc2



So ... could you help me more with the information requested?


Thanks a lot!!!

Mike

 

[Winfield Hill]

[email protected] wrote...

I'm looking an easy way to design a dual complementaty SPST switch
with a single control line in order to replace an obsolete Tesas
Instrument IC: TL604CP

You checked with Rochester Electronics? http://www.rocelec.com

Could it be possible to design a such switch using a CMOS CD4066
or by using a couple of fets?

The TL604 is a DPST switch, with a single control line, in an 8-pin
package. It has the feature that when one switch is on, the other
is off. There are a number of DPST switches on the market with this
feature, but none of them are in 8-pin packages (even if they were,
it's unlikely they'd have the same unusual TI pinout). However many
of these switches are available in small soic packages suitable for
making a mini-DIP sized substitute PCB. There are also some 8-pin
SPDT switches available. It's possible your TL604 application has
its two DPST sections wired in common to make a SPDT. In that case
you can consider one of these switches. Yes, the pinout is wrong,
but hey! Sorry about that.

 

[N. Thornton]

Thanks for your answer.

In fact, I have an old peavey Deuce series VT with 3 IC TL604CP
defect. What I'm looking for is an easy way to replace them. The
TL604CP is an obsolete part and to get them ... I have to order 100 of
them at $2.90 us each.

The only information that I could provide you is the supply voltage
+16 and -16 Volts. The control voltage is about 8 volts.

I'm trying to figure out how to do it ... but I'm not a specialist in
the field of circuit design.

I know that it is possible to design a simple circuit with a couple of
resistors and FET or using a CD4066.

Here is what I found:


FET1 FET2
input ---- R1---- | ----------| |----------------------- output
| | |
| ------
| | |
|- |
Vc2 ---- |
|- vc1
|
|
|
GND


This is a Jfet zero signal switch. The series jfet is connected with
its source on the buss. This is a virtual earth, so the control
voltage to the gate will effectiveley be grounded referenced.

Q1 OFF ON
Q2 ON OFF
Vout OFF ON

and:


Voltage control ---------- VC1 ----Vc1
|
|
|
----- inverter ---vc2



So ... could you help me more with the information requested?


Thanks a lot!!!

Mike

Im not really understanding where the problem lies. Discrete fets or a
4066 should do this fine. I'm assuming youre switching audio inputs.
With a fet, toggling the gate hi/lo switches the main channel on or
off. 2 can be used when greater ron/roff ratio is needed.


NT

 

[[email protected]]

Thanks for the hint!

Mike