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J

Jens Gydesen

Jan 1, 1970
0
Hi,

I need a switch or some kind of FET etc. that has a low impedans (10 Ohm)
when no supply is present.

There is no room for some kind of relay, the housing max hight is 1.1mm

Thanks,

regards Jens
 
J

Jim Thompson

Jan 1, 1970
0
Hi,

I need a switch or some kind of FET etc. that has a low impedans (10 Ohm)
when no supply is present.

There is no room for some kind of relay, the housing max hight is 1.1mm

Thanks,

regards Jens

--------------------------------------------------------------------------------
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Isn't that a JFET? But 10 ohms might be hard to find.

What other conditions apply?

...Jim Thompson
 
J

J.A. Legris

Jan 1, 1970
0
Jens said:
Hi,

I need a switch or some kind of FET etc. that has a low impedans (10 Ohm)
when no supply is present.

There is no room for some kind of relay, the housing max hight is 1.1mm

Thanks,

regards Jens

--------------------------------------------------------------------------------
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Den har indtil videre sparet mig for at få 2618 spam-mails
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Hent en gratis SPAMfighter her.

Supertex makes several depletion-mode mosfets, but even they will be a
tight fit in 1.1 mm of headroom. They require a negative gate voltage
to switch them off.

http://www.supertex.com/products/datasheets/102
 
P

PeteS

Jan 1, 1970
0
Jens said:
Hi,

I need a switch or some kind of FET etc. that has a low impedans (10 Ohm)
when no supply is present.

There is no room for some kind of relay, the housing max hight is 1.1mm

Thanks,

regards Jens

--------------------------------------------------------------------------------
Jeg beskyttes af den gratis SPAMfighter til privatbrugere.
Den har indtil videre sparet mig for at få 2618 spam-mails
Betalende brugere får ikke denne besked i deres e-mails.
Hent en gratis SPAMfighter her.

What is the specific application? (Schematics appreciated to a.b.s.e. if
possible).

It's possible an enhancement mode P-channel device with gate pulled low
might do what is required, a depletion mode device, a JFET or even a
diode - depends on what is required.

Cheers

PeteS
 
J

Jens Gydesen

Jan 1, 1970
0
Hi,

the job for the FET is to shortend a 13MHz RFID receiver, and open for it
when required.

The RFID receiver must be shortend when the battery is discharged.

Regards Jens
 
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