Identical opamp circuits..but one has split supply, other has single supply.

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treez

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Hello,
The following two opamp circuits (schematic attached) are exactly the same except for the fact that one has a 5V single supply and the other has a +/-5V dual supply. They both have the same shape of input signal which is also shown attached.
The opamps are LT1013's

LT1013 datasheet:
http://cds.linear.com/docs/en/datasheet/10134fe.pdf

If the circuit is made on a PCB, will the outputs be exactly the same for each of the circuits?
LTspice simulation also attached but it is not thought that it will be completely accurate
 

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  • Opamp schematic.pdf
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  • Input signal.jpg
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  • LT1013 opamp circuits.TXT
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The output can't be exactly the same because the first stage has about 100 mV saturation voltage when sinking current. The output will be different by this amount in single supply.
 
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Thanks, is that the only difference?, i mean, will the single supply one suffer reduced bandwidth when its output is at zero volts?....and this would distort the output waveshape other than you already kindly expalined?

Also, would this 100mV saturation voltage still be there if the MCP6001 opamp was used as the single supply opamp? Its datasheet doesnt allure.

MCP6001 datasheet
**broken link removed**
 
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MCP6001 has less than 10 mV saturation voltage, see FIGURE 2-14
 
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The MCP6001 has a max total supply voltage of 7V, so using a +/-5V supply will kill it....

In general, amplifiers will suffer poorer dynamic performance when their inputs or outputs are biased near their limits.
 

Thanks, i meant comparing the 0-5V MCP6001 circuit with the 0-5V LT1013 circuit.

Do you suspect the ltspice simulator does not simulate this worsened dynamic performance near the rails?
 

It's usually mentioned in SPICE model comments which parameters are modeled and which aren't. I would expect that output voltage range is basically correctly modeled.
 
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Did you check the negative voltage?
I think the voltage is not negative.
 

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