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MITSUMI
Protection of Lithium Ion Batteries (two cells in series) MM1292
Protection of Lithium Ion Batteries (two cells in series)
Monolithic IC MM1292
Outline
This IC is for protecting a lithium ion battery from overcharging, excess discharging, and overcurrent. If abnormalities occur during charging and excess voltage is applied, it has a function that turns off the external FET switch when voltage is applied to each battery beyond a specified time (overcharging detection). It also has a function that turns off the external FET switch when the voltage for each battery falls below a set voltage, to prevent excess discharge when discharging the battery (discharging detection). At that time, the IC is switched to low current consumption mode. Also, when there is a large current flow due to shorting or other reasons, there is a function for turning off the external FET switch (overcurrent detection). These functions comprise a protection circuit, with few external parts, for lithium ion batteries.
2-Cell Protection ICs
Model name MM1302A MM1292C MM1292D MM1302E MM1302F MM1302G MM1292H MM1292J MM1292K MM1292L Overcharge protection Detection voltage Hysteresis 4.25±0.05V 10mV 4.25±0.05V 200mV 4.35±0.05V 200mV 4.10±0.05V 10mV 4.35±0.05V 10mV 4.215±35V 10mV 4.30±0.05V 220mV 4.25±0.05V 220mV 4.25±0.05V 220mV 4.25±0.05V 220mV Overdischarge protection Detection voltage Hysteresis 2.3V±0.1V 700mV 2.4V±0.1V 600mV 2.4V±0.1V 600mV 2.4V±0.1V 600mV None 2.3V±0.1V 700mV 2.05V±0.1V 950mV 2.4V±0.1V 600mV 2.4V±0.1V 600mV 2.2V±0.1V 800mV Overcurrent Detection voltage 220±20mV 150±15mV 150±15mV 150±15mV None 220±20mV 170±15mV 150±15mV 150±15mV 100±10mV
Features
1. Current consumption (during overcharging) 2. Current consumption (normal) 3. Current consumption (during excess discharging) 4. Current consumption (during excess discharging) 5. Overcharge detection voltage (Ta=-20°C~+70°C) 6. Hysteresis voltage 7. Excess discharge detection voltage 8. Discharge resumption voltage 9. Overcurrent detection voltage 10.Reset after overcurrent detection 11.Operating limit voltage VCELL=4.5V VCELL=3.5V VCELL=1.9V VCELL=1.0V 80µA typ. 13µA typ. 0.5µA typ. 0.1µA max. 4.25V±50mV (detection for each cell) 200mV±60mV (detection for each cell) 2.4V±0.1V (detection for each cell) 3.0V±0.1V (detection for each cell) 150mV±15mV load release 0.9V max.
Package
SOP-8C, SOP-8D(MM1292 F) The box represents the rank resulting from the combination of protection functions.
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MITSUMI
Protection of Lithium Ion Batteries (two cells in series) MM1292
Applications
1. Cellular phones 2. Movies
Pin Assignment
1 2 8 7 6 5 3 4 5 1 2 3 4 6 7 SOP-8C/SOP-8D 8 OC GD N.C GND TD VL CS VH
Pin Description
Pin No. Pin Output Function Output pin for control of the charging control FET. When voltage detected between VH-VL or VL-GND goes over overcharge detection voltage (VALM), the output PNP1 OC Output TR (open collector output) is switched ON, and charging is prohibited by activating the element (NPN.