Op Amp for Current Sensing

[ronsimpson]

Adaptive current mode controller

I see there are different types of Adaptive current mode controllers.
I often use peak current mode. In papers from schools then measure the inductor current but I always use the switch current because it is easy to get at.
I used, decades ago, a PWM that used the ripple voltage on the output capacitor to measure inductor current. Current in the L is very related to current in the C. The loop response is good when looking at ripple voltage on the output C.
In boost supplies I usually use current mode (not adaptive). Measuring current at the switch. I have used "constant off time" or "constant on time" in current mode with very good results. I think they are very close to what you are doing.
I almost never look at current in the L directly because it takes too many parts to see it. I look at current in the switch. There was project where I looked at the current in the diode.
Link for you

 

[unclejed613]

Pick a amp with a gain bandwidth of 10mhz to 50mhz.

a TLE2072 would probably work https://www.ti.com/lit/ds/symlink/tle2072.pdf

 

[xpassionzxc]

I see there are different types of Adaptive current mode controllers.
I often use peak current mode. In papers from schools then measure the inductor current but I always use the switch current because it is easy to get at.
I used, decades ago, a PWM that used the ripple voltage on the output capacitor to measure inductor current. Current in the L is very related to current in the C. The loop response is good when looking at ripple voltage on the output C.
In boost supplies I usually use current mode (not adaptive). Measuring current at the switch. I have used "constant off time" or "constant on time" in current mode with very good results. I think they are very close to what you are doing.
I almost never look at current in the L directly because it takes too many parts to see it. I look at current in the switch. There was project where I looked at the current in the diode.
Link for you

I can see you really have great knowledge regarding boost converters!

Anyway here's my current waveform at L2 using a current probe. Looks rather noisy right. Image at Capture 1


Using a current sensor circuit(LM741) via a 0.1ohms resistor is even noisier (Already With a capacitor at the output of the op-amp to ground) hahahaha. Image at Capture 2. Dark Blue is using current sensor circuit, Light blue is via Current Probe.
You can observe that there is a slight phase shift between the two waveforms.

Without a capacitor. Image at Capture 3