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Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

In message <k1gmpk+qhts@...>, dated Mon, 27 Aug 2012, afhockey623 <jxm1092@...> writes:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Yes; if you look at the data sheet, you can see it needs + and - supplies. You can report this to the email address given in the toolbar Help -> About drop-down.
--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Instead of saying that the government is doing too little, too late or too
much, too early, say they've got is exactly right, thus throwing them into
total confusion.
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

Is this an error? I just started using LTspice and I'm trying
to use a circuit with an LT1210 and it shows two + supply
inputs instead of the usual + and - supply inputs.
Thanks gentlemen.

Hello,

Thanks for this report.
The power pin at the bottom should have a "-". I have reported now
this bug to Mike.

Please directly report this to LTC in the future, if you find
a bug. The email address is in the Help->About of the LTspice
program.

Best regards,
Helmut

--- In LTspice@..., "sawreyrw" <sawreyrw@...> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

--- In LTspice@..., "sawreyrw" <sawreyrw@> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

--- In LTspice@..., "sawreyrw" <sawreyrw@> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

Hi,

I was able to figure it out by opening up the test fixture for the op-amp. Do you know why the put an 11 Ohm resistor on the output of the opamp?

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

--- In LTspice@..., "Helmut" <helmutsennewald@> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

--- In LTspice@..., "sawreyrw" <sawreyrw@> wrote:

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

Hi,

I was able to figure it out by opening up the test fixture for the op-amp. Do you know why the put an 11 Ohm resistor on the output of the opamp?

Hello,

The original circuit is on page 1 in the datasheet.

It has a 1:3 transformer driving a 100Ohm transmission line. We
have then an input impedance of 100/3^2=11Ohm on the primary side.
Using a 11Ohm series resistance is a perfect match of this
impedance.
Maybe they removed this transformer in the jigs-example to allow
to simulate the response down to DC.

Best regards,
Helmut