TPS54519: TPS54519 SIMULATION

Hi,

When I change R7 to 30k in the default model, I get the desired 1Vout:

Can you share your waveforms for your circuit?  

As well, this device is quite old.  Did you already look at the TPS62867 (or TPSM82866A module) for your design?  They are smaller, simpler and require smaller (and lower cost) external components.

Thanks,

Chris

Hello,

thank you 

i need to simulate for above shared circuit  ,even i am getting nearly 1V for above circuit ,but if i change feedback reistance the output voltage is not chnging it remains constant to 1 volt only.

can u please suggest to get the output voltage of 1.8 and 3.3 volt for above shared circuit.

thank you

this waveform for 1.1 volt

...

Thank you for sharing your waveforms.  They look strange.

Can you share your TINA file via a private conversation with me?

Is there anything else in your simulation besides that circuit?  The waveform shows an Iload, but you don't have a load in your schematic.

As well, the waveform starts at some voltage (at t=0) and then restarts much faster than the SS time should be.

Chris

that waveform captured when the load was connected to the circuit

using this not able to get 1.8 volt and 3.3 volt ,i am getting only 1.2 volt maximum is this transient model is working properly

Hi,

The model works fine on my side.  Can you share the file you are trying to simulate, including your modifications?  There may be some wrong setting, etc.

Chris

this module we are using since long,so we cannot change this part 

how to analyse ripple current and is this model is stable 

for 1.1 volt i got these waveform

this circuit i tried simulating in ltspice

Yes i imported unencrypted files to lt spice

ok i will check

thank you 

thank you for your support

please can tell how to analyse ripple current in tina ti software for this TPS54519 buck converter

Hi Sanjana,

After the converter reaches steady state, you can zoom in on the waveform to examine the signals cycle by cycle.

Chris

hello,

from this method can we able to analyze stability and ripple current.

thank you

can u please show how to analyze ripple current and stability analysis for above spice model in tina TI.

thank you

can we do AC analysis for the above buck converter to analyse stability and ripple current

To do AC analysis, you need to use the average model SLVMBS8.TSC.  Inside it, there are instructions for how to obtain the loop response.

Chris

how to analyse ripple current for TPS54519 model 

I'm not sure what you mean by ripple current.  Could you share an example, or check with your co-workers, on what is expected from your company on that?

Chris

OK SURE

hello ,this  is the average model connection and stability analysis result can u please tell whether the obtained graph is correct

above design is the transient model ,is the above  average model is correct according to this transient model

can u please tell how to identify whether the stability analysis waveform is correct or not

thank you

Hi Sanjana,

The behaviors that cause line and load reg are either not part of the TPS54519 device (PCB layout parasitics, external component variation, etc.) or are not modeled in the device model.  You need to get these values from lab measurements of your circuit.

In the average model, your C11 value looks quite large at 22uF.  22pF is a more typical value for this cap.

It looks like you changed the injection circuitry component C13's value.  I would leave it as the default 100k value.

Chris

ok
thank you
i will look into it

how to merge the gain and phase margin waveform into single axis

hi
can u please explain this average model circuit parameter connection

Hi Sanjana,

I don't think you can combine the graphs into 1.

I'm not sure what your second question is.

Chris

The second question is why we need to connect injection capacitor and inductor 

slvmbs8_1V8.TSC

for the above parameter in the circuit connection need to get the waveform of gain and phase as shown above

but i am not getting the above waveform ,can u please check what is error in the above circuit connection.

thank you

The injection capacitor and inductor are required for Tina to accurately run the analysis.

There must be some difference between your bench data and the simulation.  I would make sure that the simulation components match what your design gives.  Possible discrepancies include: the output capacitance--you need to include all the capacitance on the output bus, regardless of which page of the schematic it is on; also, you need to use the effective capacitance, which includes DC bias loss (the Tina model notes that the output cap value has been derated to account for this); the connection of C3--usually, this goes across both R1 and R9.

Chris