Part Number: TPS43061
Hi there,
we use TPS43061 to boost Vin=13~19V to Vout = 20V, max 6A load, switching freq.=380KHZ with R78=150K resistor.
Problem: When Vin=19V, Vout ripple is basically ok (~200mVpp), but there seems to be very large Spikes about 600~800mVpp. Apparentlt the spike is synchronized with SW(pin12) waveform. I guess this may be the so-called "Switching Niose", and its too large for us. We tried increase R73 and R79 to 10ohm, but no use.
Could you help advice how to eliminate or reduce the spike as small as possible? I found most info on web are about snubber desgin for flyback or buck, there seems to be little relevant article on this specific problem for boost circuit. Thanks!
As below, pic1 is SCH. Pic 2 channel 1 is Vout ripple and spikes measured with AC coupled and with short GND clip, channel 2 is SW pin. Pic 3 is just the zoomed in of the spike details.
Pic1
Pic 2
Pic 3
