■DESCRIPTION

The MB3790 is designed to control power supplies to SRAM, logic IC, or other circuit devices and protects them against momentary power failures by using backup batteries. In addition to its function to supply the power to these devices, it has a function to switch the source of power to the primary or secondary backup battery when the power supply voltage drops below a predetermined level. Also, it outputs a reset signal when the power supply turns on or off or when a fault occurs in the power supply. Ideally designed as a single-chip IC for power supply control, the MB3790 consumes only a minimal current and comes in a thin-type package. Therefore, it is best suited for power supply control in memory cards and similar other devices.

■FEATURES

• Input circuit current consumption when non-loaded: 50 µA [typ]

• Output drive current: 200 mA [max]

• Resistance between input and output: 0.5 ohms [typ]

• Input power-down detection level: 4.2 V ± 2.5 %

• On-chip power-on reset circuit

• Primary battery voltage-down detection levels: 2.65 V, 2.37 V