Part Number: LM3478
Hi!
Vacation is over and I have now done some measurements related to the original question (which was locked).
Vin=3.5V
Ch1, yellow, 5V/div: Gate of M1, used for triggering (during this measure, a 22Ohm resistor was connected between DR and the gate)
Ch2, green, 50mV/div: Isense pin
Ch3, red, 2V/div: Drain of M1
Ch4, blue, 50mV/div and 1.35V offset: Comp pin
Oscilloscope BW = 500MHz
Zoom on short pulse:
There are glitches on Isense and Comp (partly due to bad probing I guess...), but as far as I can see, they come after DR switches off.
The same glitches can be seen on the correct pulse, with same relation to DR goes low:
As I mentioned in the original question, for this test I have used a separate supply for the LM3478 Vin-pin only. For the scope shot above, both supplies were 3.5V. If I change the LM3478 supply to 3.6V (keeping 3.5V to L1), there will be no short pulses.
Any idea why I get this short pulses?
BR
/P-O