Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Protection of Lithium-Ion Batteries (for Double-Protect) Monolithic IC MM1451 Outline This IC is used for double-protection of lithium-ion batteries with from one to three cells, and has an ultracompact package. Short-circuits between cells accommodate series connections of one to three cells. Features 1. Overcharge detection voltage accuracy (0°C to 50°C) 2. Consumption current (Vcell=3.8V) 3. Consumption current (Vcell=2.3V) 4. Pin I/O current between cells (Vcell=3.8V) 5. Delay time on overcharge voltage detection (Ct=0.22µF) 6. Output current (Vcell=VCC=4.5 V) ±50 mV/cell. 3µA typ. 0.3µA typ. 0.3µA max. 1.5S typ. 500µA typ. Package VSOP-8B Applications IC for double-protection of lithium-ion batteries with one to three cells. Pin Assignment 8 1 7 2 6 3 VSOP-8B 5 4 1 V3 2 V2 3 V1 4 GND 5 Ct 6 N.C 7 OUT 8 VCC MITSUMI Block Diagram Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Pin Description Pin No. Pin name Functions 1 V3 3-cell power supply 2 V2 2-cell power supply 3 V1 1-cell power supply 5 Ct Delay capacity pin 7 OUT OUT pin Equivalent circuit diagram Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Absolute Maximun Ratings (Ta=25°C) Item Symbol Ratings Unit Operating temparature TOPR -20~+80 °C Storage temparature TSTG -40~+125 °C VCC Input voltage VCC V1 Input voltage *1 V1 V2 Input voltage *1 V2 -0.3~18 V V3 Input voltage *1 V3 Ct pin voltage *2 VCT -0.3~18 V VOUT pin voltage VOUT -0.3~18 V Allowable loss Pd 170 mW Note 1 : 1 18V > = V3 > = V2 > = V1 > = -0.3 Note 2 : 2 Do not impress current of 300µA or more on the Ct pin. * * Electrical Characteristics 1 (Except where noted otherwise, Ta=25°C, VCEL=V3-V2=V2-V1=V1-GND, VCC=3 VCEL) Item Symbol Measurement conditions Current consumption 1 I1 VCEL=3.8V 3.0 6.0 µA Current consumption 2 I2 VCEL=2.3V 0.3 0.5 µA Pin I/O current between cells I3 VCEL=3.8V (between V3, V2, V1) ±0.0 ±0.3 µA Overcharge detection voltage VS VCEL=L H Ta= - 20~+70°C 4.400 4.450 4.500 V Hysterisis voltage Hys Overcharge detection delay time TPLH Output current IOH VCEL=L H L Min. Typ. Max. Unit 35 50 65 mV Ct=0.22µF 1.0 1.5 2.0 S VCEL=VCC=4.5V VO=3V 100 500 µA Electrical Characteristics 2 (Except where noted otherwise, Ta=25°C, VCEL=V3-V2=V2-V1=V1-GND, VCC=3 Measurement conditions VCEL) Item Symbol Min. Typ. Max. Unit Current consumption 1 I1 VCEL=3.8V, VCC=VCEL 3 3.0 6.0 µA Current consumption 2 I2 VCEL=2.3V, VCC=VCEL 3 0.3 0.5 µA Pin I/O current between cells I3 ±0.0 ±0.3 µA Overcharge detection voltage VS 4.400 4.450 4.500 V Hysterisis voltage Hys Overcharge detection delay time TPLH Output current Output leakage current VCEL=3.8V (between V3, V2, V1) VCEL=L H Ta=-20~+70°C VCEL=L H L 35 50 65 mV Ct=0.22µF 1.0 1.5 2.0 S IOH VCEL=VCC=4.6V VO=3V 100 500 ILEAK VCEL=3.8V, VCC=18V µA 0.1 µA Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Electrical Characteristics 3 (Except where noted otherwise, Ta=25°C, VCEL=V3-V2=V2-V1=V1-GND, VCC=3 Item Symbol Current consumption 1 I1 VCEL=3.8V, VCC=VCEL 3 2.5 3.5 µA Current consumption 2 I2 VCEL=3.8V, VCC=VCEL 3 1.5 2.5 µA Current consumption 3 I3 VCEL=2.3V, VCC=VCEL 3 0.15 0.3 µA Current consumption 4 I4 VCEL=2.3V, VCC=VCEL 3 0.1 0.2 µA Pin I/O current between cells I3 ±0.0 ±0.3 µA Overcharge detection voltage VS 4.400 4.450 4.500 V Hysterisis voltage Hys Overcharge detection delay time TPLH Output current Output leakage current Measuring Circuit Measurement conditions VCEL ) Min. Typ. Max. Unit VCEL=3.8V (between V3, V2, V1) VCEL=L H Ta=-20~+70°C VCEL=L H L 35 50 65 mV Ct=0.22µF 1.0 1.5 2.0 S IOH VCEL=VCC=4.6V VO=3V 100 500 ILEAK VCEL=3.8V, VCC=18V µA 0.1 µA Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Application Circuit Delay time Td(S) = 7 CCt (µF) Note 1: Can support 1, 2 or 3 cells by shorting each cell. However, be sure to connect a battery for V3 cell. V3 cell may not operate correctly when shorted. Note 2: When connecting batteries, be sure to connect in the following order: GND V3, and VCC V1OR V2. Note 3: Output may go ON momentarily when starting up power supply. If this error output during startup becomes a problem, connect the VCC pin last. Note 4: Operation can not be guaranteed for connections other than the above. Timing Chart 4.45V 4.40V V1~V3 1.5S Ct 1.8V 0.6V OUT OUT (at Ct short) (at Ct open) Note: Output goes low simultaneously with overcharge detection at Ct pin short and open. Protection of Lithium-Ion Batteries (for Double-Protect) MM1451 MITSUMI Characteristics Output delay time 6 3.0 5 2.5 Delay time (S) Output voltage (V) Detection voltage 4 3 2 2200p 2200ppm pm 1.0 0 1 2 3 0.0 4.400 4.450 -25 Input voltage (No delay) (V) Consumption current (µA) Pin I/O current between cells (µA) 1 1.5 2 75 Pin I/O current between cells 6 5 4 3 2 1 0 0.5 25 Temperature (°C) Consumption current 0 -500p -500ppm pm 1.5 0.5 1 0 2.0 2.5 3 3.5 4 Cell voltage (V) 4.5 0.3 0.2 0.1 0 -0.1 -0.2 -0.3 0 0.5 1 1.5 2 2.5 3 3.5 4 Cell voltage (V) 4.5