Other Parts Discussed in Thread: LM3150, LM25145, LM5145
Hi Sirs,
I want to measure the loop gain of this Evaluation Board.
is there a dedicated pin for injecting small ac signals?
Best reagards
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Hi Sirs,
I want to measure the loop gain of this Evaluation Board.
is there a dedicated pin for injecting small ac signals?
Best reagards
In addition, it is necessary to know the output waveform of the ERM control part to calculate the loop gain of this board. However, there is no detailed information of the corresponding signal in the datasheet. Could you provide the above-mentioned waveforms?

Hello,
Looks like the EVM doesn't have a 50 Ohm resistor for bode plot signal injection.
Regards,
Tim
I doubt this EVM was done in Altium, hence the files are not available.
Also, my understanding is the ERM block details are proprietary. It shouldn't be required for measurement purposes.
Regards,
Tim
Because we want to verify our theoretical model, which is related to the slope of the two input signals of the modulator at the intersection.
The existence of the ERM will affect the slope of vfb. So we need to know the output waveform of the ERM.
look forward to receiving your reply soon.
Are there other chips similar to LM3510, but no ERM part and ramp compensation in the input of the modulator?
Thanks very much!
“The ERM block details are proprietary”, did this mean that the output amplitude of this block cannot be told to us?
Take a look at the LM25145 42V and LM5145 75V voltage-mode controllers with readily identifiable loop characteristics. This family of controllers provides better effieicny than the LM3150 and is thus preferred. Also, the Altium design files are in the product folder.
Regards,
Tim
Thanks very much!
However, we want to verify the theoretical models of a COT-controlled buck converter. So we have to choose a chip with only the COT mode.
Looking forward to receiving your reply as soon as possible.
Maybe check the PSPICE model to see what is publicly available. A conventional COT controller (without ERM) is the LM(2)5085.
Regards,
Tim