MB3889 Fujitsu Microelectronics, Inc., MB3889 Datasheet - Page 24

• Manufacturer Part Number: MB3889
• Description: 2-channel Dc/dc Converter Ic With Overcurrent Protection Symmetrical-phase Type
• Manufacturer: Fujitsu Microelectronics, Inc.

24
MB3889
Protection circuit
Overcurrent protection circuit
Short-circuit protection
Overvoltage protection circuit
Under voltage lockout protection circuit
OUTPUT STATES DURING PROTECTION CIRCUIT OPERATION
The table below lists the output states with each protection circuits actuated.
RESETTING THE LATCH OF EACH PROTECTION CIRCUIT
When the overvoltage, overcurrent, or short-circuit protection circuit detects each abnormality, it sets the latch
to fix the output at the "L" level. The PWRGOOD terminal (pin 12) is fixed at the "L" level upon abnormality
detection by each protection circuit.
To reset the actuated protection circuit, either the power supply turn off and on again or set the CTL terminal
(pin 6) to the "L" level to lower the VREF terminal (pin 8) voltage to 1.7 V (Min) or less. It can also be reset by
setting both of the CTL1 terminal (pin 9) and CTL2 terminal (pin 10) to the "L" level.
Output terminal
CH1
CH2
CH1
CH2
CH1
CH2
OUT1-1
L
L
L
L
L
L
L
CH1
OUT2-1
H
H
L
L
L
L
L
OUT1-2
L
L
L
L
L
L
L
CH2
OUT2-2
H
H
L
L
L
L
L
PWRGOOD
L
L
L
L
L
L
L