Outline
These ICs were developed for D-RAM and dummy S-RAM battery back-up. D-RAM and dummy S-RAM power supplies differ from that of S-RAMs because 5V or 3.3V of power supply is required even during battery back-up. Therefore, these ICs provide voltage from a stable power supply during both normal operation and back-up. Also, the internal stable power supply switches automatically to battery back-up if the main power supply voltage goes down for any reason.

Features
1. Battery back-up
    MM1025
        Current consumption 600µA typ.
        Input/output voltage difference IL=40mA 0.25V typ.
        Output current 40mA max.
    MM1174
        Current consumption 300µA typ.
        Input/output voltage difference IL=40mA 0.13V typ.
        Output current 40mA max.
2. Normal operation
    MM1025
        Input/output voltage difference IL=80mA (built-in transistor) 0.29V typ.
        Output current VCC=6V 80mA typ.
        External transistor drive current VCC= 6V 15mA typ.
        Current consumption 900µA max.
    MM1174 (for external transistor)
        Input/output voltage difference IL=200mA 0.13V typ.
        Output current Depends on external transistor
        External transistor drive current (no built-in TR) VCC=3.6V 10mA typ.
        Current consumption 500µA max.
3. Switching voltage from VCC to Battery VCC=High Low
    MM1025 4.9V typ.
    MM1174 3.25V typ.
4. VCC-Battery forced switching and detection voltage adjustment possible

Applications
1. Memory cards (D-RAM cards, other)
2. PCs, word processors and other equipment with D-RAMs
3. Fax machines, photocopiers and other office equipment with D-RAMs