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LM13700: Can LM13700 be powered with 3.3V single power supply?

Wang Carson
Prodigy 110 points
Part Number: LM13700

Hi ,

I would like to know whether the LM13700 OTA can be powered  with 3.3V single power supply? Through the Multisim simulation, when power with 3.3V,

The LM13700 works properly. However, It seems LM13700 OTA function can not be  worked properly when building actual circuit test.

Br,

Carson 

  • 0
    Guru 140200 points

    Hi Carson,

    in the header of Spice model of LM12700 it is mentioned that the model works down to +/-2V. The typical common mode input voltage range specification of datasheet says that the input voltage must stay 1.5V away from the supply rails and that the output can swing 0.8V to the rails (without any load). So, theoretically, your +3.3V supply voltage (+/-1.65V) or better a +4V supply voltage (+/-2V) as mentioned in the model should be sufficient. But keep in mind that with such a low supply voltage you don't have any headroom for the signal itself. Only a small output signal could be achieved then which might not be a good idea with the rather high noise the LM13700 superimposes to the signal.

    And if you consider the maximum specification of common mode input voltage range and the input voltage has to stay 3V away from the supply rails, then a minimum supply voltage of +6V (+/-3V) was necessary, again without any headroom for the signal itself.

    So, what minimum supply voltage is necessary depends on the circuit, on the input and output signal amplitude and what minimum common mode input voltage range your LM13700 shows.

    Kai 

  • 0
    TI__Guru*** 140136 points

    Hello Carson,

    The recommended minimum supply is 9.5V ([V+] - [V-]) . At 3.3V, operation will be extremely limited. 

  • 0 in reply to Ron Michallick
    Prodigy 110 points

    Hi Ron,

    Thanks for reply, Yes , I  know 9.5V min in dataseet. In my application,  5V is maxim power rail can be supplled。 That‘s why   3.3V/5V  single power supply for LM13700.

    Br

    Carson

  • 0 in reply to kai klaas69
    Prodigy 110 points

    Hi kai,

    I am very sorry that we have suspended further verification due to the Chinese Spring Festival. We have considered the common mode and signal range you mentioned in the design.they  do not exceed the limit.

    we will review if there are any bugs in the circuit.I'll let you know when I get .

    Br

    Carson

  • 0 in reply to Wang Carson
    TI__Guru*** 140136 points

    Carson, Good luck 

  • 0 in reply to Wang Carson
    Guru 140200 points

    Hi Wang,

    I'm eager to hear whether you can make the LM13700 to run with 5V supply voltage Relaxed

    Kai

  • 0 in reply to kai klaas69
    Prodigy 110 points

    Hi Kai，

    There is no essential difference in the performance of 3.3V or 5V single-ended power supply.We have tried 5V single-ended power supply before the first submission.

    At present, we are trying to adjust Id and Ibias to see the improvement. BTW, The  input signal  is DC offset Vcc/2, AC Vpp=1V. 

    Br,

  • 0 in reply to Wang Carson
    Guru 140200 points

    Thanks for the info Relaxed

    Kai