MITSUMI Protection of Lithium Ion Batteries (one cell) MM1301 Protection of Lithium Ion Batteries (one cell) Monolithic IC MM1301 Outline This IC provides protection for the MM1291 series of compact, high-precision type lithium ion batteries which have been in use for some time. Precision of ±30mV is guaranteed between 0°C and +50°C, and this IC can be used in applications where precision is crucial. 1-Cell Protection ICs Overcharge Overdischarge Release Overcurrent detection detection Hysteresis Dead time Delay detection voltage SOP-8 VSOP-8 voltage Overcurrent Detec time shot-mode MM1301 AW 4.27V 200mV at 2.3V 2.9V 100mV 0.9V BW 4.17V 100mV Ctd= 2.3V 2.9V 100mV 0.9V min. 5mS min. 5mS CW 4.18V 100mV 0.082µF 2.3V 2.9V 125mV 0.45V DW 4.28V 220mV 2.3V 2.9V 50mV 0.45V EF 4.20V 100mV min. 0.5S 2.3V 2.9V typ. 10mS 125mV typ. 10mS 0.45V FW 4.28V 100mV 2.3V 2.9V 50mV 0.45V GW 4.18V 220mV typ. 1S 2.3V 2.9V max. 15mS 125mV max. 15mS 0.45V HW 4.35V 220mV 2.3V 2.9V 50mV 0.45V JW 4.20V 220mV max. 1.5S 2.3V 2.9V 125mV 0.45V Note : Under open-load conditions, returns to normal mode from overcurrent mode. (For MM1291A to G, J, M, 5MΩ or higher; for MM1291H, K, 50MΩ or higher) Package Features 1 Overcharge detection voltage Ta=0~+50°C VCEL±30mV 1.0S typ. 2 Overcharge detection delay time CTD=0.082µF 10µA typ. 3 Current consumption (normal operation VCEL=3.5V) 0.7µA typ. 4 Current consumption (overdischarge operation VCEL=1.9V) 5 Overcurrent cancel conditions Load removed : Load of 5MΩ or greater across battery pack terminals Package VSOP-8A Applications Lithium ion battery pack (for battery protection) Protection of Lithium Ion Batteries (one cell) MM1301 MITSUMI Block Diagram Pin Assignment 8 1 7 2 6 3 5 4 VSOP-8A 1 GND 2 GD 3 CS 4 OC 5 N.C 6 TD 7 VCC 8 VIN Pin Description Pin No. Pin name 1 GND Function Negative power supply pin Also serves as voltage detection pin for battery connected between VIN and GND Gate connection pin for discharge-control FET (N-ch) 2 GD Turns the gate off in overdischarge mode and overcurrent mode. Gate is turned on in overcharge and normal modes. Overcurrent detection input pin 3 CS Discharge current detected by connection to drain pin of discharge-control FET. Discharge current = (CS-GND voltage)/(FET turn-on resistance) Protection of Lithium Ion Batteries (one cell) MM1301 MITSUMI Overcharge detection output pin 4 OC 5 N.C 6 TD Overcharge detection dead time setting pin 7 VCC Positive power supply voltage pin 8 VIN Voltage detection pin for battery connected between VIN and GND On overcharge, an external transistor is driven to turn off the charge-control FET (N-ch) Notes : Overcharge mode : Battery voltage > overcharge detection voltage Normal mode : Overdischarge detection voltage < battery voltage < overcharge detection voltage, discharge current < overcurrent detection level Overdischarge mode : Overdischarge detection voltage > battery voltage Overcurrent mode : Discharge current > overdischarge detection level=CS-GND voltage > discharge current turn-on resistance (discharge-control FET) Absolute Maximun Ratings (Ta=25°C) Item Symbol Ratings Units Storage temperature TSTG -40~+125 °C Operating temperature TOPR -20~+70 °C Power supply voltage VCC max. -0.3~+18 V OC pin voltage VOC max. CS pin voltage VCS max. -0.6~VCC V Allowable loss Pd 300 mW Recommended Operating Conditions Item Symbol Ratings Units Operating temperature TOPR -20~+70 °C Operating voltage VOP +0.9~+18 V Electrical Characteristics (Except where noted otherwise, Ta=25°C) Item Symbol Overcharge detection voltage VOC Overcharge release voltage VOCR Overcharge sensing hysteresis VOCH=VOC-VOCR Measurement conditions Min. Typ. Max. Units VCC=VIN=L 4.15 4.18 4.21 V 4.04 4.09 4.14 V 60 90 120 mV H, Ta=0~50°C VCC=VIN=H L VOCH Overdischarge detection voltage VODC1 VCC=VIN=H L 2.20 2.30 2.40 V Overdischarge release voltage VODR VCC=VIN=L H 2.78 2.90 3.02 V Overcurrent detection threshold VCS VCS=L H 112 125 138 mV Overcurrent short-circuit detection VCSS 0.35 0.45 0.55 V Load open : Load of 5MΩ or greater across battery pack terminals Overcurrent release conditions Consumption current 1 (Normal mode) (IS1=ICC+IIN) Consumption current 2 (Overdischarge mode) IS1 VCC=VIN=3.5V 10.0 14.0 µA IS2 VCC=VIN=1.9V 0.7 1.0 µA Protection of Lithium Ion Batteries (one cell) MM1301 MITSUMI Overcurrent detection delay time 1 tCS1 Overcurrent detection delay time 2 tCS2 Overdischarge detection delay time tOD Overcharge detection delay time tOC OC pin output current IOC VCC=VIN=4.5V VGDH VCC=VIN=3.5V GD pin "H" Output voltage (Normal mode) GD pin "L" Output voltage (Overcurrent mode) GD pin "L" Output voltage (Overdischarge mode) VGDL1 VGDL2 5.0 10.0 15.0 mS 30 100 µS 5.0 10.0 15.0 mS 0.5 1.0 1.5 S -30 µA *1 CTD=0.082µF *2 VCC VCC -0.3 -0.1 VCC=VIN=3.5V VCS=0.5V VCC=VIN=1.5V V 0.1 0.3 V 0.2 0.4 V *1: The overcurrent short mode delay time (overcurrent delay time 2) is the response time of the IC itself. In actual use, the time required for discharge of the gate capacitance of the discharge-controlling FET is added to this. When excessive currents cause considerable voltage fluctuation, the bias current within the IC may be temporarily turned off, so that the response time is lengthened. The time constant of the capacitance and resistance connected to the power supply pin should be set to at least 100µS/V, to limit power supply fluctuations. *2: Use the following formula to calculate the overcharge detection time: overcharge detection dead time tOC = 12.2 CTD [S] [where CTD is the external capacitance in µF] Timing Chart Overcharge cutoff voltage Overcharge expulsion voltage Cell voltage Overdischarge expulsion voltage TD FET gate (charge control) Overdischarge cutoff voltage FET gate (discharge control) removing load Normal mode Normal mode Normal mode Overcharge mode Overcurrent Protection of Lithium Ion Batteries (one cell) MM1301 MITSUMI Application circuits Characteristics 50 40 30 20 ICC 10 IIN 0 1.0 2.0 3.0 4.0 Overcharge detection time Overcharge detection time (S) Power supply current (ICC, IIN) (µA) Power supply current vs power supply voltage 5.0 Power supply voltage (ICC, VIN) (V) 10 1 0.1 0.01 0.001 0.01 0.1 External capacitance (CTD) (µF)