mb3883pv Fujitsu Microelectronics, Inc., mb3883pv Datasheet - Page 22

• Manufacturer Part Number: mb3883pv
• Description: 6-ch Dc/dc Converter Ic With Synchronous Rectification For Voltage Step-up And Step-down
• Manufacturer: Fujitsu Microelectronics, Inc.

22
MB3883
2. Soft Start Settings
Example: The soft start time until CH6 output voltage reaches 95% of the set voltage is determined as follows:
Note : The short-circuit detection function remains working during soft start operation on channels 1 through 5.
• CH6 soft start time
The soft start operation is determined by the capacitor (C+IN6) connected to the C+IN6 terminal (pin 5). The
soft start time depends on the input voltage and load current.
CH6 soft start time
• CH1 to CH5 soft start time
CH1 to CH5 soft start time
SETTING THE TRIANGULAR OSCILLATOR FREQUENCY
The triangular oscillator frequency is determined by the timing capacitor (C
26), and the timing resistor (R
Triangular oscillator frequency
ts (s) : = 0.07
ts (s) : = 1.25
f
OSC
ts (s)
(kHz) : =
C
C
C
C
IN6
T
S
IN6
(F)
(pF) R
( F)
900000
( F)
37.5 (k )
100 (k )
V
T
C IN6
(k )
C
T
) connected to the RT terminal (pin 25).
IN6
C IN6
CH6 soft start equivalent circuit
62.5 (k )
5
(1.26 V)
ln 1
(
(37.5 k )
(62.5 k )
(VB : 2 V)
V
1.26 (V)
C IN6
(V)
Error
Amp.6
)
T
) connected to the CT terminal (pin