MM3114 Mitsumi Electronics, Corp., MM3114 Datasheet - Page 8

• Manufacturer Part Number: MM3114
• Description: Protection For Lithium-ion Batteries
• Manufacturer: Mitsumi Electronics, Corp.

MITSUMI
Description
1. Over charge detector
· This IC monitors individual cell voltages. If any cell voltage exceeds the overcharge detection voltage (4.35V
· After detecting overcharge when the all cell voltages are coming down to a level lower than overcharge
· After detecting overcharge in the cell voltage, connecting system load to the battery charger makes load
· There are delay time set in IC when the overcharge and the overcharge release are detected. When the V
· A level shifter incorporated in a buffer drive for the OV to the V
2. Over discharge detector
· This IC monitors individual cell voltages. If any cell voltage crosses the overdischarge detection voltage
· The release from the overdischarge is done only by connecting the charger. Charging current is supplied
· The C
· An output delay time for the overdischarge detection is fixed internally (40m styp.). When cell voltage
· All the circuits are stopped, and after the overdischarge is detected, it is assumed the state of the standby,
· The output type of DCHG pin is CMOS having high level of V
typ.) from a low value higher than the overcharge detection voltage, the IC sense a overcharging and
external charging control Pch MOS FET turns to OFF with OV pin being high level.
release voltage (4.15V typ.) external charging control Pch MOS FET turns to ON with OV pin being high level.
current allowable supplied to parasitic diode of charging control FET. The OV pin level would be high when
the cell voltage level is coming down to a level below the overcharge detection voltage by continuous
sending a load current.
level is going up to a higher level than overcharge detection voltage if the cell voltage would be back to a
level lower than the overcharge detection voltage within a time period of the over charge release delay time
(100ms typ). The overcharge detection does not release when returning to former state in the overcharge
release dead time (20ms typ.) even if the load is connected after the charger is removed when the cell
voltage is lower than the overcharge release voltage with the overcharge detected.
V
(2.30V typ.) from high value to a value lower than the overdischarge detection voltage , this IC sense an
overdischarge and an external discharging control Pch MOS FET turns to OFF with DCHG pin being at high
level.
through a parasitic diode of Pch MOS FET when the cell voltage is below the overdischarge detection
voltage to the connection of the charger, and the DCHG pin enters the state which can be discharged by
becoming low level, and turning on Pch MOS FET when the cell voltage rises more than the overdischarge
detection voltage.
the maximum value of 0V charging lowest operating voltage when the voltage of the battery is 0V.
becomes lower the over discharge detection voltage if cell voltage higher more than the over discharge
detection voltage in delay time even does not enter the over discharge detection mode. Moreover, when the
over discharge release, delay time is set (20ms typ.).
and decreases the current (standby current) which IC consumes as much as possible (The V
max.).
SS
voltage with CMOS buffer.
OUT
pin becomes high level and charging current is supplied if the voltage of the charger is more than
Protection for Lithium-Ion Batteries (4-serial cells) MM3114 Series
DD
IN
and low level of V
pin voltage and the low level of OV is set to
SS
.
CELL
=2V 0.1µA
DD