FUJITSU SEMICONDUCTOR
DATA SHEET
DS04-27400-11E
ASSP For power supply applications
BIPOLAR
Power Supply Monitor
MB3771
■
DESCRIPTION
The Fujitsu MB3771 is designed to monitor the voltage level of one or two power supplies (+5 V and an arbitrary
voltage) in a microprocessor circuit, memory board in large-size computer, for example.
If the circuit’s power supply deviates more than a specified amount, then the MB3771 generates a reset signal to
the microprocessor. Thus, the computer data is protected from accidental erasure.
Using the MB3771 requires few external components. To monitor only a +5 V supply, the MB3771 requires the
connection of one external capacitor. The level of an arbitrary detection voltage is determined by two external
resistors. The MB3771 is available in an 8-pin Dual In-Line, Single In-Line Package or space saving Flat Package.
■
FEATURES
•
•
•
•
•
•
•
•
•
•
Precision voltage detection
(V
SA
=
4.2 V
±
2.5
%)
User selectable threshold level with hysteresis (V
SB
= 1.23 V
±
1.5
%)
Monitors the voltage of one or two power supplies (5 V and an arbitrary voltage,
>1.23
V)
Usable as over voltage detector
Low voltage output for reset signal (V
CC
= 0.8 V Typ)
Minimal number of external components (one capacitor Min)
Low power dissipation (I
CC
= 0.35 mA Typ, V
CC
= 5 V)
Detection threshold voltage has hysteresis function
Reference voltage is connectable.
One type of package (SOP-8pin : 1 type)
■
APPLICATION
• Industrial Equipment
• Arcade Amusement
etc.
Copyright©2003-2006 FUJITSU LIMITED All rights reserved
FUJITSU [ FUJITSU COMPONENT LIMITED. ]
