Hi!
I follow the steps in the slva636, see p.8 and 9:
1. The first pole (Fp0) of the compensator is placed at the origin from an integrator.
Fp0 = 23 Hz
C1 = 1 / (2 pi R1 Fp0) = 1 / (2 pi 930k 23Hz) = 7.44nF -> 7.5 nF
2. The compensation zero (Fz1) is placed at one-fifth the selected crossover frequency.
The crossover frequency Fcross = 0.6 kHz <= Min((Frhpz / 5), (1/10 Fsw)) <= Min(3.6kHz / 5, (1/10 200k))
Fz1 = 100 Hz <= 1/5 Fcross = 1/5 * 0.6 kHz
R2 = Fp0 R1 / Fz1 = 23Hz * 930k / 100Hz = 213.9k -> 215 kOhm
3. The second pole (fp1) of the compensator is placed coincident with the ESR zero or the RHP zero frequency, which is lower.
Fp1 = 3.6kHz <= Min( 1/(2 pi Cesr Cout), Frhpz ) = Min( 1/(2 pi 8mOhm 480uF), Frhpz ) = Min( 41.4 kHz, 3.6 kHz )
C3 = Fz1 / (2 pi R1 Fp0 Fp1) = 100Hz / (2 pi 930k 23Hz 3.6kHz) = 206 pF -> 200pF
I see on the schematic, Figure 10:
C1 = 7.5 nF, ok
R2 = 215 kOhm, ok
C3 = 0.1nF, why?
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