MB39A132QN-G-ERE1 Datasheet, PDF (44/56 Pages) Fujitsu Component Limited. – ASSP For Power Management Applications (Rechargeable Battery) Synchronous Rectification DC/DC Converter IC for Charging Li-ion Battery

MB39A132
(2) Constant current (CC) mode phase compensation circuit
In constant current mode, since the output capacitor impedance has little effects on the loop response
characteristic, connect the 1pole-1zero phase compensation circuit with the output pin (COMP2) of the error
amplifier 2 (gm amplifier).
1pole-1zero phase compensation circuit
BATT Current Amp2
17
-
Rs
12
+
-
COMP2
15
To PWM Comp.
+INC2
+
Error Amp2
Rc
Vrefint2
Cc
RC and Cc of the phase lead circuit can be found by the following formula.
RC =: 1.2 × 10⁴ ×
fCO × L
Rs × VIN
CC =:
√L × Co
Rc
Rs : Charge current detection resistance [Ω]
VIN : Switching power supply voltage [V]
L : Inductor value [H]
Co : Output capacitance [F]
fCO : Crossover frequency [Hz]
44
DS04–27265–3E