MM1026 Datasheet, PDF (1/10 Pages) Mitsubishi Electric Semiconductor – Monolithic IC MM1026, 1245, 1080 ,1134

MITSUMI
System Reset (with battery back-up) MM1026, 1245, 1080, 1134
System Reset (with battery back-up)
Monolithic IC MM1026, 1245, 1080 ,1134
Outline
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These ICs protect S-RAM data in back-up mode (CS signal makes R-SAM CE pin low and CE pin high) when
power supply voltage goes below a certain set voltage (detection voltage 3.5V, 4.2V or 4.5V typ.). Further, it
switches from main power supply to battery back-up when power supply voltage drops. Conversely, when
power supply rises, it first switches the S-RAM from battery back-up to main power supply (switching voltage
3.3V typ.), then from back-up mode to normal mode (CS signal makes S-RAM CE pin high and CE pin low).
These signal processes provide reliable protection against data damage.
Features
MM1026
• Power supply switching circuit (switching between main power supply and battery)
• CS control for S-RAM (normal mode : S-RAM can be accessed; back-up mode: S-RAM can not be
accessed low current consumption mode)
• Reset output
MM1245
• Power supply switching circuit
• CS control for S-RAM
• CS control signal delay, power supply line chattering removal approx. 1S max.
• Supply current from main power supply can be increased by external power transistor
MM1080
• Power supply switching circuit
• CS control for S-RAM
• Low current consumption 60µA typ.
MM1134
• Power supply switching circuit
• CS control for S-RAM
• Gate circuit with CS signal
Characteristics
1. Battery back-up
1. Low IC current consumption (loss current)
2. Drop voltage inside IC (input/output voltage difference)
3. Reverse current (reverse leak current)
2. Normal operation
1. Drop voltage inside IC (input/output voltage difference)
2. Output voltage
VCC=5V
3. Battery-VCC switching voltage
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4. Detection voltage (CS, CS, reset output)
IO=100µA
IO=50µA
IO=50mA
A : 3.5V typ.
B : 4.2V typ.
C : 4.5V typ.
0.3µA typ.
0.3V typ.
0.1µA max.
0.2V typ.
4.8V typ.
3.3V typ.