mm1412 Mitsumi Electronics, Corp., mm1412 Datasheet - Page 7

• Manufacturer Part Number: mm1412
• Description: Protection For Lithium-ion Batteries
• Manufacturer: Mitsumi Electronics, Corp.

MITSUMI
MITSUMI
Timing Chart
Description
V
V
Dischage
control
dead time
setting
GD
TD
OC
H
H
This IC is a lithium ion battery (2-cell in-series type) protection IC. It has built-in overcharge detection,
overdischarge detection and overcurrent detection circuits, and controls the FET (external N-MOS FET) that
controls charge and discharge.
The operation modes can be divided broadly into four, as follows.
1) Overcharge mode
2) Normal mode
3) Overdischarge mode
4) Overcurrent mode
Overcharge
Overdischarge
Overcharge
Overdischarge
Over current
dead time
The battery voltage of either the upper cell or lower cell goes above overcharge detection voltage.
Detection operation delay for overcharge detection can be set with the dead time setting pin.
The battery voltage of both upper cells and lower cells is above overdischarge detection voltage and below
overcharge detection voltage.
The battery voltage of either the upper cell or lower cell drops below overdischarge detection voltage. Dead
time for overdischarge detection is set internally. Overdischarge mode is released when charging takes
place and the voltage goes above overdischarge detection voltage. Also, reset will occur even without
charging if battery voltage goes above overdischarge release voltage, but the set value is high. (This
function is provided as a measure for cases when charging can not be detected. Further, this release
voltage has a temperature coefficient of -6mV/°C.)
The voltage between CS-GND goes above overcurrent detection voltage during discharge.
Keep cirquit
Gate off
Over load
Open load
Overcharge
dead time
Overdischarge
HI-impedance
detection
Protection for Lithium-Ion Batteries (2-serial cells) MM1412
Charge sensing
Power down
Overdischarge
dead time
Overdischarge
Keep overcharge
Short load
Overdischarge
dead time
Power
down