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TPS22860: Pl share customized Turn- on & turn- off timing diagrams

Part Number: TPS22860

Hi all,

I have a design requirement as shown in figure below:

This is  a gain block RF amplifier (MNA-6A+ from minicircuits) which needs to be DC biased through a Load switch.

Project requirement is a faster turn -ON time ( less than or equal to 5us ) & turn-off time can be 100 us (max).

Switching characteristics of TPS22860 looks like satisfying my requirement but still I need suggestion from experts.

Kindly share the timing diagram for my requirement.

REgards,

Rajan

  • Hi Rajan,

    Could you please clarify what you mean by "timing diagram"? The TPS22860 has a turn on time in the nano seconds range, and the turn off time is dependent on how quickly the load (150mA) is able to discharge the output capacitance. The switch itself will turn off very quickly and should not have a large impact on the turn off time.

    Thanks,

    Alek Kaknevicius

  • In reply to Aleksandras_Kaknevicius:

    Hi Alek,
    Thanks for the reply.
    By timing diagram I mean curves of "ON", "Vout"(magnitude rise) Vs time scale during turn-On & turn-off .

    Is the Turn-ON time of TPS22860 remains in nanoseconds irrespective of type of load?

    Kindly share the TPS22860 spice transient models so that I can simulate this load switch using Spice simulator.


    REgards,
    Rajan

  • In reply to rajan:

    Hi Rajan,

    A stronger load (higher current) will cause the device to turn on a bit slower and a weaker load (lower current) will cause the device to turn on faster. I think it would be pretty unlikely for the rise time to exceed 5us, but the best way to be sure is by testing your specific load.

    For the model, please post in the simulation models forum to request a SPICE model. The product folder currently has the TINA-TI model.

    Thanks,

    Alek Kaknevicius

  • In reply to Aleksandras_Kaknevicius:

    Hi Alek,
    I am unable to find TPS22860 load switch model in TINA-TI software.

    Kindly help
    Regards,
    Rajan
  • In reply to rajan:

    Hi Rajan,

    You are correct, I was looking at the wrong link. It turns out that we do not have a TINA-TI or PSPICE model available, and we do not have any plans to develop one for this device.

    Thanks,

    Alek Kaknevicius

  • In reply to Aleksandras_Kaknevicius:

    Hi all,

    This week I received the samples of TPS22860 from ti.com. Thanks TI for samples support. Fast delivery.

    I have evaluated this DC load switch using a standard SOT23-6 evaluation board to find the Turn-On delay of TPS22860.

    For my DC power requirements, the switching -ON time of TPS22860 is nearly 9nsec. Kindly check the attached screen shots and test setup.

    Vbias = VIn = +5.0V , Channel-1 gives Von { properties : Square Waveform ( V low  = 0V, V High  = 5.0V, Period  = 1.0msec, Phase = 0 deg, " Output port  = LoadHigh Z ")} = channel-2 : Ref (to compare the output waveform)

    Regards,

    Rajan Kumar