grizedale
Advanced Member level 3
Hello,
We are doing TPS40210 boost converter.
TPS40210 DATASHEET:
https://www.ti.com/lit/ds/symlink/tps40210.pdf
Vin = 12V
Vout = 19V
Iout(max) = 1.62A
F(sw) = 500KHz (Sync'd with diode method)
C(in) = 20uF ceramic
C(out) = 20uF ceramic, then 1.5uH series inductor, then 10uF ceramic capacitor.
Current sense resistor = 10mR
Upper feedback divider resistor = 61.9K
RC series network connected round error amplifier = 4.99K, 22nF
(a 47pF ceramic cap is across this RC series network)
Boost inductor = 10uH.
We are OK in max or high load, but in light load, we are seeing an instability involving a ripple on the Vout of frequency about 5KHz.
-Do you know why this is?
We are doing TPS40210 boost converter.
TPS40210 DATASHEET:
https://www.ti.com/lit/ds/symlink/tps40210.pdf
Vin = 12V
Vout = 19V
Iout(max) = 1.62A
F(sw) = 500KHz (Sync'd with diode method)
C(in) = 20uF ceramic
C(out) = 20uF ceramic, then 1.5uH series inductor, then 10uF ceramic capacitor.
Current sense resistor = 10mR
Upper feedback divider resistor = 61.9K
RC series network connected round error amplifier = 4.99K, 22nF
(a 47pF ceramic cap is across this RC series network)
Boost inductor = 10uH.
We are OK in max or high load, but in light load, we are seeing an instability involving a ripple on the Vout of frequency about 5KHz.
-Do you know why this is?