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TPS55332-Q1: How do I observe board diagram with TINA-TI?

Yoshiki Ochi
Genius 9685 points
Part Number: TPS55332-Q1
Other Parts Discussed in Thread: TINA-TI,

Hi team, 

Could you tell me how to observe board diagram with TINA-TI?

I found that reference design of TPS55332: https://www.ti.com/lit/tsc/slvmae4

However, I cannot see any board diagram from that file when I changed some of them. What I did are shown below.

  • I changed input voltage generator which are "cold clank" and "EN" to 12V battery
  • I added input voltage generator between FB and OUTPUT line.
  • I did "AC transfer characteristics..." but error occurred

I want to see loop stability in the case output capacitors and loop compensation circuit are changed by TINA-TI.

Regards,
Ochi

TPS55332_20200511_E2E.TSC

  • 0
    TI__Mastermind 31315 points

    Hi Ochi-san,

    Your model is currently using the transient model. If you would like to check the AC transfer characteristics, you will need to use the average model.

    However, I've noticed that there does not seem to be an average model for the TPS55332. In this case, can you try to set up a load transient? You can analyze the ouptut voltage ripple and see the stability from there.

    Thanks,

    Richard

  • 0 in reply to Richard Fu22
    TI__Genius 9685 points

    Hi Richard, 

    OK, I will try that.

    Now I would like to find calculated or estimated value of compensation circuit.
    Could you tell me some values and answers related to figure.10 in TPS55332-Q1 datasheet?

    1. What is the initial gain of error amplifier? Also, Is the phase (f=0Hz) 0 degree?
    2. Which kind of compensation circuit type does feed forward compensation circuit (1 zero and 1 pole)?
      I guessed it is type2 compensation circuit, is it correct?
    3. Why does the blue line in phase characteristics affect as phase decreasing like pole? Isn't blue line in phase characteristics RHP zero?
    4. As same as question ②.  

    Regards,
    Ochi

  • 0 in reply to Yoshiki Ochi
    TI__Mastermind 31315 points

    Hi Ochi-san,

    The plot is to show how different compensation networks will affect the stability of the system. You should read as the plot starting initially with the double-pole system, and then look at how a RHP-zero or feed-forward compensation will affect the double-pole system (the dotted blue and red lines). The solid red and blue lines show what the frequency response of the RHP-zero and feed-forward system look like in isolation. 

    1) Error amplifier is implemented as an op-amp. You can assume as a very high value, which will be rolled off with a low frequency pole.

    2) Type-II compensation gives you a zero and a pole. 

    3) RHP zero should give an increase in gain like a zero would provide (+20 dB), and a decrease in phase like a pole would provide (-90 degree phase shift). 

    4) If you add the phase-contribution from the compensation network to the "Reflected RHP-Zero impact" phase, you will get the red line.

    In compensating this part, the compensation strategy in application design is that of Type-I compensation, which will roll off the gain so that your cross-over frequency is lower than the RHPZ, as you can see in section 8.2.2.8.

    Thanks,

    Richard