Fujitsu MB3845 Switch User Manual


 
DS04-27604-2E
FUJITSU SEMICONDUCTOR
DATA SHEET
ASSP For Power Supply Applications
Power Management 2-ch Switch IC
MB3842/MB3845
DESCRIPTION
The MB3842/3845 is a power management switch with built-in 2-channel low-on resistance (typ. 100m) switch.
Output control is by means of a control signal, and the MB3842 is designed for high-active operation (output on
when EN is Hi), while the MB3845 is designed for low-active operation (output on when EN
is low.)
To provide adaptability to a variety of operations, the MB3842/3845 features low input voltage (V
IN
> 2.5V)
operation and stable low-on resistance independent of input voltage. The switching current limit can be set from
100mA to 600mA by using external resistance, and when overcurrent conditions are detected the OC output goes
low to provide an external notification signal.
V
IN
is divided between the two channels, which operate independently of each other.
In addition, an off-state reverse current prevention function is provided to ensure accurate on/off switching action.
FEATURES
Low on resistance switch (typ. 100m)
Low input voltage operation (2.5 V to 5.5 V)
Switch current (max. 0.6 A)
•UVLO :V
IN
threshold 2.3V/2.1 V hysteresis 200 mV
ENABLE :EN threshold EN 1.4V/1.6 V for MB3842, EN 1/2 V
IN
for MB3845
:Power supply current at output off = 0µA EN < 0.8V for MB3842, EN = V
IN
for MB3845
External setting for soft start time and switch current limit.
Over-temperature detection (switch latched off), over-current detection (not latched)
OC pin flag set following overcurrent detection, over-temperature detection, or UVLO detection.
Reverse current prevention at OFF (V
IN
1.5 V)
Either channel may be operated alone.
PACKAGE
20-pin plastic SSOP
(FPT-20P-M03)