mm1446 Mitsumi Electronics, Corp., mm1446 Datasheet - Page 3

• Manufacturer Part Number: mm1446
• Description: Protection Of Lithium Ion Battery One Cell
• Manufacturer: Mitsumi Electronics, Corp.

Pin Description
Overcharge Mode : Battery Voltage > Overcharge Det. Voltage
Nomal Mode : Overdischarge Det. Voltage < Battery Voltage < Overcharge Det. Voltage
Overdischarge Mode : Overdischarge Det. Voltage > Battery Voltage
Overcurrent Mode : Discharge Current > Overcurrent Det. Voltage / External Det. Resistor
PIN No. PIN Name
1
2
3
4
5
6
7
8
GND
OC2
OC1
CS1
CS2
V
GD
TD
CC
Discharge Current < Overcurrent Det. Voltage / External Det. resistor
Negative power supply for this IC. Also act as detection voltage pin for the battery
connected between Vcc-GND.
Detection pin for voltage between CS1-GND.
When CS1 is connected with the Source of discharge FET, Detects overcurrent using an
external resistor and discharge current.
When CS1 is connected with CS2(4PIN), and connects with the Dorein of charge and
discharge FET, Detects overcurrent using an On state resistor of discharge control FET
and discharge current.
Discharge Current=CS1-GND Voltage / External Resistor
CS1-GND Voltage / On state resistance of discharge control FET
N-ch FET gate connection pin for discharge control. Switches gate OFF when
overdischarge is detected, and for current protection. Switches gate ON when overcharge
is detected, and in normal state.
Detection pin for overcurrent mode release and start-up voltage.
Detected load release resets from overcurrent mode. When the battery is being charged
and the Voltage between CS2-GND during overdischarge mode falls bellow start-up
voltage, the bias current is drained to the interior circuit and operating status result.
Control pin for N-ch FET for charge control. Switches FET OFF by activating an external
transistor when overcharge is detected.
This operation continues until the voltage falls bellow overcharge release voltage.
Overcharge detection dead time setting pin.
Overcharge detection output (input) pin. For overcharge detection, output goes high without
dead time set by TD pin. (Hysteresis does not go on until OC2 output goes high.)
Charging control FET is turned off by the OC2 pin when OC1 pin input is high.
Positive power supply for this IC. Also act as detection voltage pin for the battery connected
between Vcc-GND.
T
C
ARAM
TD
: TD pin external capacitance value (µF)
. = . 10.0 C
TD
(s)
Function