Protection of Lithium Ion Batteries MM1414 MITSUMI Protection of Lithium Ion Batteries Monolithic IC MM1414 Outline This IC is use to protect lithium-ion batteries consisting of three or four cells. It adopts a compact package and has the functions of previous models, with functions for overcharge detection, overdischarge detection and overcurrent detection. A dead time can be set externally. Features 1. Overcharge detection voltage accuracy ±25mV/cell 2. Consumption current (Vcell=4.4V) 50µA typ. 3. Consumption current (Vcell=3.5V) 23µA typ. 4. Consumption current (Vcell=1.8V) 2µA typ. 5. Overcharge sensing dead time: can be set externally 6. PF detection: warning signal when cell voltage falls Package TSOP-20A Applications IC for protection of lithium-ion batteries consisting of three or four cells Pin Assignment 20 19 18 17 16 15 14 13 12 11 1 2 3 4 5 6 7 8 9 10 TSOP-20A 1 OV 11 SEL 2 N.C 12 N.C 3 CS 13 CON 4 N.C 14 N.C 5 DCHG 15 V1 6 N.C 16 V2 7 CDC 17 V3 8 COL 18 V4 9 COV 19 N.C 10 GND 20 VCC MITSUMI Block Diagram Protection of Lithium Ion Batteries MM1414 Protection of Lithium Ion Batteries MM1414 MITSUMI Pin Description Pin No. Pin name I/O Functions Overcharge detection output pin 1 OV Output NPNTr open collector output Normal: high impedance Overcharge: Low 2 N.C Not connected Overcurrent detection pin Monitors load current equivalently by the voltage drop between discharge control 3 CS Input FET source and drain, and makes DCHG pin high when the voltage goes below overcurrent detection voltage, turning off discharge control FET. After overcurrent detection, current flows from this pin and when there is a light load, overcurrent mode is released. This function does not operate in discharge mode. 4 N.C Not connected Discharge control FET (P-ch) drive pin 5 DCHG Output Normal: Low Overdischarge: High 6 N.C Not connected 7 CDC Input 8 COL Input 9 COV Input 10 GND Input 11 SEL Input 12 N.C Overdischarge detection dead time setting pin Dead time can be set by connecting a capacitor between CDC pin and ground. Overcurrent detection dead time setting pin Dead time can be set by connecting a capacitor between COL pin and ground. Overcharge detection dead time setting pin Dead time can be set by connecting a capacitor between COV pin and ground. Ground pin 3 cell switch pin SEL pin = GND: 3 cell (no V1 cell detection) SEL pin = VCC: 4 cell Not connected Discharge FET ON/OFF pin 13 CON Input CON pin low; DCHG pin low CON pin high; DCHG pin high 14 N.C Not connected 15 V1 Input V1 cell high side voltage input pin 16 V2 Input V2 cell high side voltage and V3 cell low side voltage input pin 17 V3 Input V3 cell high side voltage and V4 cell low side voltage input pin 18 V4 Input V4 cell high side voltage input pin 19 N.C 20 VCC Not connected Input Power supply input pin Protection of Lithium Ion Batteries MM1414 MITSUMI Pin Description Equivalent circuit diagram Equivalent circuit diagram 1 ; OV 9 ; COV 3 ; CS 11 ; SEL 5 ; DCHG 13 ; CON 7 ; CDC 15 ; V1 8 ; COL 16 ; V2 Protection of Lithium Ion Batteries MM1414 MITSUMI Equivalent circuit diagram Equivalent circuit diagram 17 ; V3 18 ; V4 Absolute Maximum Ratings (Ta=5°C) Item Symbol Ratings Unit Storage temperature TSTG -40~+125 °C Operating temperature TOPR -20~+70 °C Power supply voltage VCC max. -0.3~24 V OV pin impressed voltage VOV max. -0.3~24 V SEL pin impressed voltage VSEL max. -0.3~24 V CON pin impressed voltage VCON max. -0.3~24 V Allowable loss Pd 300 mW Recommended Operating Conditions Item Symbol Ratings Unit Operating temperature TOPR -20~+70 °C Operating voltage VOPR +1.8~+24 V Protection of Lithium Ion Batteries MM1414 MITSUMI Electrical Characteristics (Except where noted otherwise, Ta=25°C, VCC=V4+V3+V2+V1, VCEL=3.5V, CON=0V, SEL=0V) Item Symbol Measurement conditions Consumption current (VCC pin) 1 ICC1 VCELL=4.4V, CON=0V 55 110 µA Consumption current (VCC pin) 2 ICC2 VCELL=3.5V, CON=0V 27 50 µA Consumption current (VCC pin) 3 ICC3 VCELL=1.8V, CON=0V 2 4 µA Consumption current (VCC pin) 4 ICC4 VCELL=3.5V, CON=VCC 12 20 µA Consumption current (VCC pin) 5 ICC5 VCELL=1.8V, CON=VCC 1 2 µA Consumption current (V4 pin) 1 I1V4 VCELL=4.4V 10 20 µA Consumption current (V4 pin) 2 I2V4 VCELL=3.5V 8 15 µA Consumption current (V4 pin) 3 I3V4 VCELL=1.8V 2.5 5.0 µA V3 pin input current IV3 VCELL=3.5V ±300 nA V2 pin input current IV2 VCELL=3.5V ±300 nA V1 pin input current IV1 VCELL=3.5V ±300 nA Overcharge detection voltage VCELLU Overcharge hysteresis voltage VU Overcharge sensing dead time tOV Overdischarge detection voltage VCELLS Discharge resume voltage VCELLD VCELL : 4.2V 4.4V VCELL : 4.2V 4.4V Min. Typ. Max. Unit A, C 4.325 4.350 4.375 3.9V 140 200 260 mV 0.5 1.0 1.5 S A, B 1.90 2.00 2.10 C, D 2.20 2.30 2.40 2.85 3.00 3.15 A, B 0.75 1.00 1.25 C, D 0.45 0.70 0.95 COV=0.1µF VCELL : 3.5V 1.8V VCELL : 1.8V V B, D 4.225 4.250 4.275 3.5V VCELLD-VCELLS V V Overdischarge hysteresis voltage VDS Overdischarge sensing dead time tCDC CDC=0.1µF 0.5 1.0 1.5 S Overcurrent detection voltage VOC VCC-VCS, DCHG 135 150 165 mV 20 40 mV 10 15 mS 1.5 3.0 mS 10 15 mS Overcurrent hysteresis voltage VOC Overcurrent sensing dead time 1 tCOL1 COL=0.001µF Overcurrent sensing dead time 2 tCOL2 COL=0.001µF, VCC-CS>1.0V Overcurrent sensing dead time 3 tCOL3 COL=0.001µF Overcurrent reset conditions 5 5 V Load release conditions 500kΩ DCHG pin source current ISODCH VCELL=1.8V, SW1 : A VDCHG=VCC-0.8V 20 µA DCHG pin sink current ISIDCH VCELL=3.5V, SW1 : A VDCHG=0.8V 20 µA DCHG pin output voltage H VTHDCH VCC-VDCHG, ISO=20µA, SW1 : B 0.8 V DCHG pin output voltage L VTHDCL VDCHG-GND, ISI=-20µA, SW1 : B 0.8 V OV pin sink current ISIOV VOV=0.4V, Ta=-20~+70°C OV pin leak current ILKOV VOV=24V 0.1 µA CON pin L voltage DCHG= "High" 0.4 V CON pin H voltage DCHG= "Low" CON pin current VCELL=3.5V, CON=0.4V SEL pin L voltage for 3 cell SEL pin H voltage for 4 cell SEL pin current VCELL=3.5V, SEL=0.4V 100 µA VCC-0.4 V 1 2 µA 0.4 V VCC-0.4 V 1 2 µA Protection of Lithium Ion Batteries MM1414 MITSUMI Measuring Circuit Timing Chart For overcharge Charge OFF Overcharge detection voltage Cell voltage Overcharge release voltage COV pin Sensing dead OV pin (for pull up) Normal state Overcharge Normal state Protection of Lithium Ion Batteries MM1414 MITSUMI For overdischarge Discharge OFF Charge start Discharge resume voltage Overdischarge Cell voltag detection voltage CON pin Sensing dead CDC pin DCHG pin Normal state Normal state External control Overdischarge Normal state Normal state Normal state For overcurrent Overcurrent Load release Current flows from CS pin CS pin COL pin Sensing dead Reset dead DCHG pin Normal state Overcurrent Normal state Protection of Lithium Ion Batteries MM1414 MITSUMI Application Circuit Characteristics Overcharge & Overdischarge Sensing Dead Times Overcurrent Sensing Dead Time 1, Overcurrent Reset Dead Time 100 Dead time (mS) Dead time (S) 10 1 0.1 0.01 0.001 0.01 0.1 1 Pin capacitance (µF) 10 1 100 1000 COL pin capacitance (pF) Overcurrent Sensing Dead Time 2 Overcurrent Sensing Dead Time 2 (mS) 100 10 1 0 100 1000 10000 COL pin capacitance (pF) Note: The above characteristics are representative values only, and are not guaranteed. 10000