AIC1803 Three-Cell Lithium-Ion Battery Protection IC n FEATURES n DESCRIPTION l Ultra-Low Quiescent Current at 13A (V CELL=3.5V). l Ultra-Low Power-Down Current at 1.3A (V CELL=2.3V) l Wide Supply Voltage Range: 2V to 18V. Precision Overcharge Protection Voltage: l The AIC1803 is designed to protect the lithiumion battery from damage or degrading the lifetime due to overcharging, overdischarging and overcurrent for three-cell lithium-ion battery powered systems such as notebook PCs. It can also provide the cell-balancing "bleeding" function to automatically discharge the overcharged cell until the overcharge condition is released. 4.35V 30mV for the AIC1803A 4.30V 30mV for the AIC1803B 4.25V 30mV for the AIC1803C 4.20V 30mV for the AIC1803D l l l n l n Externally Set Overcharge, Overdischarge and Overcurrent Delay Time. Built-in Cell-balancing Bleeding Network under Overcharge Condition. Three Detection Levels for Overcurrent Protection. Safe and full utilization charging is ensured by the accurate 30mV overcharge detection. Four different specification values for overcharge protection voltage are provided for various protection requirements. The very low standby current drains little current from the cell while in storage. APPLICATIONS Protection IC for Three-Cell Lithium-Ion Battery Pack. TYPICAL APPLICATION CIRCUIT R8 1K 1 2 OC CS VCC VC1 16 R4 C4 0.1 F 1K M1 FUSE M2 15 BATT+ C1 R1 2K 0.1 F 3 4 OD UD1 NC VC2 R5 1M BAT1 14 Q1 13 R2 2K C2 0.1 F 5 6 CTD 82nF CTI 2.2nF 7 CTC 82nF 8 TD TI UD2 VC3 TC UD3 NC GND BAT2 12 R6 1M R7 1M 11 R3 33K 10 C3 0.1F BAT3 9 BATT- AIC1803 Protection Circuit for Three-Cell Lithium-Ion Battery Pack Analog Integrations Corporation 4F, 9 Industry E. 9th Rd, Science-Based Industrial Park, Hsinchu, Taiwan TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw DS-1803-02 012102 1 AIC1803 n ORDERING INFORMATION AIC1803-XCXXX PIN CONFIGURATION PACKING TYPE TR: TAPE & REEL TB: TUBE TOP VIEW PACKAGE TYPE S: SOP-8 OVERCHARGE PROTECTION VOLTAGE A: 4.35V B: 4.30V C: 4.25V D: 4.20V OC 1 CS 16 VCC 2 15 VC1 OD 3 14 UD1 NC 4 13 VC2 TD 5 12 UD2 TI 6 TC 7 11 VC3 10 UD3 NC 8 9 GND Example: AIC1803-ACSTR a 4.35V version, in SO-16 Package & Tape & Reel Packing Type n ABSOLUTE MAXIMUM RATINGS Supply Voltage ................................................... ... ... ... ... ... ....................................... 18V DC Voltage Applied on other Pins ............ ... ... ... ... ... ... ..... ....................................... 18V Operating Temperature Range............................... ... ... ... ... ... ......................... -20C~70C Storage Temperature Range ................................ ... ..... ... ... ..................... - 65C ~125C n TEST CIRCUIT ROC 1M I OC S1 1 V OC R8 V CS 2 OC VCC CS VC1 16 15 I CC IC 1 1K 3 VOD 4 OD UD1 NC VC2 14 13 I UD1 R4 1K C4 0.1 F C1 0.1F R1 2K V C1 I C2 VC2 R2 2K 5 6 CTD 82nF CTI 7 2.2nF CTC 8 TD UD2 TI VC3 UD3 GND TC NC 12 11 IUD2 C2 0.1F IC 3 R3 33K 10 9 I UD3 VC3 C3 0.1F 82nF AIC1803 2 AIC1803 n ELECTRICAL CHARACTERISTICS (T =25C, unless otherwise specified.) A PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT VCC Pin Input Current in Normal VCELL=3.5V Mode ICC 13 20 A VC1 Pin Input Current in Normal VCELL=3.5V Mode IC1 0.4 1.0 A VC2 Pin Input Current in Normal VCELL=3.5V Mode IC2 0.4 1.0 A VC3 Pin Input Current in Normal VCELL=3.5V Mode IC3 0.2 0.5 A Vcc Pin Input Current in PowerDown Mode VCELL=2.3V ICC(PD) 1.3 2 A VC1,VC2,VC3 Input Current in Power-Down Mode VCELL=2.3V IC(PD) 0.01 0.15 A 4.32 4.35 4.38 4.27 4.30 4.33 AIC1803C 4.22 4.25 4.28 AIC1803D 4.17 4.20 4.23 AIC1803A AIC1803B Overcharge Protection Voltage VOCP V Overcharge Hysteresis Voltage VHYS 150 200 250 mV Overdischarge Protection Voltage VODP 2.27 2.40 2.53 V Overdischarge Release Voltage VODR 2.85 3.00 3.15 V VOIP 135 150 165 mV TOC 10 21 32 mS TOD 10 21 32 mS Overcurrent Protection Voltage VCELL=3.5V VCELL 1= VOCP-30mV Overcharge Delay Time VOCP+30mV VCELL2= VCELL3=3.5 V , CTC =1nF VCELL1= 2.5V 2.3V Overdischarge Delay Time VCELL2= VCELL3=3.5V , CTD =1nF 3 AIC1803 n ELECTRICAL CHARACTERISTICS (Continued) PARAMETER TEST CONDITIONS SYMBOL MIN. TYP. MAX. UNIT TOI1 7 15 23 mS TOI2 2 4 6 mS TOI3 150 300 450 S IOC 2.0 2.8 3.6 mA VCELL= 3.5V Overcurrent Delay Time (1) Overcurrent Delay Time (2) Overcurrent Delay Time (3) 0.15V<VCC - VCS <0.3V, CTI =2.2nF VCELL=3.5V, 0.3V<VCC -V CS<1.0V VCELL=3.5V VCC - VCS>1.0V VCELL1=4.4V, OC Pin Sink Current VCELL2= VCELL3=3.5V, OC Pin Short to VCC OD Pin Output "H" Voltage VDH OD Pin Output "L" Voltage VDL 0.01 0.15 V VCH VCC +0.4 VCC +0.55 V Charge Detection Threshold Voltage VCELL=2.3V VCC -0.15V VCC -0.03V V UD1 Pin Cell-Balancing Bleeding VCELL1=4.4V, Current VCELL2= VCELL3=3.5V IUD1 5.9 8.4 10.9 mA UD2 Pin Cell-Balancing Bleeding VCELL2=4.4V, Current VCELL1= VCELL3=3.5V IUD2 6.1 8.7 11.3 mA UD3 Pin Cell-Balancing Bleeding VCELL3=4.4V, Current VCELL1= VCELL2=3.5V IUD3 6.4 9.2 12.0 mA Note: VCELL means the battery cell voltage. Therefore, VCELL1 = VC1 - V C2 VCELL2 = VC2 - VC3 VCELL3 = VC3 4 AIC1803 n TYPICAL PERFORMANCE CHARACTERISTICS Vcc Pin Power-Down Current (A) 15 Vcc Pin Input Current ( A) TA =25C 14 13 12 11 7.8 8.4 9.0 9.6 10.2 10.8 11.4 1.3 TA =25 C 1.2 1.1 1.0 0.9 0.8 12.0 4.5 4.8 5.1 Fig. 1 Vcc Pin Input Current vs. Supply Voltage Vcc Pin Power-Down Current (A) Vcc Pin Input Current ( A) 6.0 6.3 6.6 6.9 2.0 V CELL =3.5V 15 1.8 14 VCELL=2.3V 1.6 13 1.4 12 1.2 11 1.0 -20 -10 0 10 20 30 40 50 60 Temperature ( C) Fig. 3 Vcc Pin Input Current vs. Temperature Overdischarge Protection Voltage (V) AIC1803C 4.26 4.24 4.22 -20 0 20 40 60 -20 -10 0 10 20 30 40 50 60 70 Temperature (C) Fig. 4 Vcc Pin Power-Down Current vs. Temperature 4.28 4.20 0.8 70 4.30 Overcharge Protection Voltage (V) 5.7 Fig. 2 Vcc Pin Power-Down Current vs. Supply Voltage 16 10 5.4 Supply Voltage (V) Supply Voltage (V) 70 Temperature (C) Fig. 5 Overcharge Protection Voltage vs. Temperature 2.42 2.41 2.40 2.39 2.38 2.37 2.36 -20 -10 0 10 20 30 40 50 60 70 Temperature (C) Fig. 6 Overdischarge Protection Voltage vs. Temperature 5 AIC1803 Overcurrent Protection Voltage (V) 152.0 151.5 V CELL=3.5V 151.0 150.5 150.0 149.5 149.0 148.5 148.0 -20 -10 0 10 20 30 40 50 60 70 Temperature(C) Fig. 7 Overcurrent Protection Voltage vs. Temperature Overcharge/Overdischarge Delay Time (mS) n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) CTC /CTD=1nF 24 22 20 18 16 14 -20 -10 0 10 20 30 40 50 60 70 Temperature( C) Fig. 8 Overcharge/Overdischarge Delay Time vs. Temperature 4.08 Overcharge Release Voltage (V) Overcurrent Delay Time 1 (mS) 22 26 20 VCELL =3.5V 18 16 14 12 10 -20 -10 0 10 20 30 40 50 60 70 Temperature ( C) Fig. 9 Overcurrent Delay Time 1 vs. Temperature 4.07 4.06 4.05 4.04 4.03 4.02 -20 -10 0 10 20 30 40 50 60 Temperature ( C) Fig. 10 Overcharge Release Voltage vs. Temperature 70 Overdischarge Release Voltage (V) 3.01 3.00 2.99 2.98 2.97 -20 -10 0 10 20 30 40 50 60 Temperature (C) Fig. 11 Overdischarge Release Voltage vs. Temperature 70 6 AIC1803 n BLOCK DIAGRAM CS 2 VC1 15 Battery Voltage Sense Circuit VC2 13 VC3 Wake-up Control VCC+0.4V 16 VCC VCC-0.15V Overcurrent Delay Circuit 11 VCC-0.3V UD1 14 3 350 VCC-1V UD2 12 Overdischarge Delay Circuit 400 UD3 10 Power-Down Control 1 OD OC Overcharge Delay Circuit 450 1.2V GND 9 7 5 6 TC TD TI 7 AIC1803 n PIN DESCRIPTIONS PIN 1: OC- PIN 2: CS- PIN 3: OD - NMOS open drain output for control of the charge control MOSFET M2. When overcharge occurs, this pin sinks current to switch the external PNP Q1 on, and charging is inhibited by turning off the charge control MOSFET M2. Input pin for current sensing. Using the drain-source voltage of the discharge control MOSFET M1 (voltage between VCC and CS), it senses discharge current during normal mode and detects whether charging current is present during power-down mode. Output pin for control of discharge control MOSFET M1. When overdischarge occurs, this pin goes high to turn off the discharge control MOSFET M1 and discharging is inhibited. PIN 4: NC - No connection PIN 5: TD - Overdischarge delay time setting pin. PIN 6: TI - Overcurrent delay pin. PIN 7: TC - Overcharge delay time setting pin. PIN 8: NC - No connection. PIN 9: GND - Ground pin. This pin is to be connected to the negative terminal of the battery cell BAT3. PIN10: UD3 - This pin is to be connected to the positive terminal of the battery cell BAT3 for cell-balancing bleeding function under overcharge condition. PIN11: VC3- Input pin for battery BAT3 voltage sensing. This pin is to be connected to the positive terminal of the battery cell BAT3. PIN12: UD2 - This pin is to be connected to the positive terminal of the battery cell BAT2 for cell-balancing bleeding function under overcharge condition. PIN13: VC2- Input pin for battery BAT2 voltage sensing. This pin is to be connected to the positive terminal of the battery cell BAT2. PIN14: UD1- This pin is to be connected to the positive terminal of the battery BAT1 for cell-balancing bleeding function under overcharge condition. PIN15: VC1- Input pin for battery BAT1 voltage sensing. This pin is to be connected to the positive terminal of the battery cell BAT1. PIN16: VCC - Power supply pin. This pin is to be connected to the positive terminal of the battery cell BAT1. time setting n APPLICATION INFORMATIONS l THE OPERATION Initialization Overcharge Protection On initial power-up, such as connecting the When the voltage of either of the battery cells battery pack for the first time to the AIC1803 , the exceeds the overcharge protection voltage (V OCP) AIC1803 enters the power-down mode . A charger beyond the overcharge delay time (TOC ) period, must be applied to the AIC1803 circuit to enable charging is inhibited by the turning-off of the the pack. charge control MOSFET M2. The overcharge 8 AIC1803 delay time is set by the external capacitor C TC detection level. TOI1 is set by the external capacitor Inhibition of charging is immediately released CTI . TOI2 and TOI3 default to 4mS and 300s when the voltage of the overcharged cell becomes respectively, and can not be adjusted due to lower than overcharge release voltage (V OCR or protection of external MOSFETs VOCP-V HYS) through discharging. Cell-Balancing Bleeding after Overcharge Overdischarge Protection When either of the battery cells is overcharged, When the voltage of either of the battery cells falls the AIC1803 provides the cell-balancing bleeding below the overdischarge protection voltage (V O D P) function to discharge the overcharged cell at beyond the overdischarge delay time (TOD ) period, about 9mA until the voltage of the overcharged discharging is inhibited by the turning-off of the cell decreases to overcharge release voltage discharge (V OCR control MOSFET M1. The or VO C P -VH Y S ). This function is overdischarge delay time is set by the external accomplished by connecting UD1, UD2, UD3 pins capacitor is to the positive terminals of battery cells BAT1, immediately released when the voltage of the CT D . Inhibition of discharging BAT2, BAT3 respectively. The bleeding current overdischarge cell becomes higher than the can be decreased by inserting resistors along overdischarge release voltage (V O D R ) through UD1 pin to BAT1 positive terminal path and UD3 charging. pin to BAT3 positive terminal path. Overcurrent Protection In normal mode, the AIC1803 continuously Power-Down after Overdischarge monitors the discharge current by sensing the When overdischarge occurs, the AIC1803 will go voltage of CS pin. If the voltage VC C -V C S exceeds into power-down mode, turning off all the timing the overcurrent protection voltage (V O I P) beyond generation and detection circuitry to reduce the the overcurrent delay time (TO I ) period, the quiescent current to about 1.3A (V CC =6.9V). In overcurrent the unusual case where one battery cell is protection circuit operates and discharging is inhibited by the turning-off of the overdischarged discharge control MOSFET M1. Discharging must overcharge condition, the AIC1803 will turn off all be inhibited for at least 256mS after overcurrent the detection circuitry except the overcharge takes place to avoid damage to external control detection circuit for the cell under overcharge MOSFETs due to rapidly switching transient condition. between BATT+ and BATT- terminals. while another one under The overcurrent condition returns to normal mode Charge Detection after Overdischarge when the load is released and the impedance When overdischarge occurs, the discharge control between the BATT+ and BATT- terminals is MOSFET M1 turns off and discharging is inhibited. 20M or higher. However, charging is still permitted through the The AIC1803 is provided with the three overcurrent detection levels (0.15V, 0.3V and 1.0V) and the three overcurrent delay time (TO I 1 , TO I 2 and TO I 3 ) corresponding to each overcurrent parasitic diode of M1. Once the charger is connected to the battery pack, the AIC1803 immediately turns on all the timing generation and detection circuitry and goes into normal mode. Charging is determined to be in progress if the CS 9 AIC1803 pin voltage is higher than VCC + 0.4V (charge of the discharge control MOSFET M1. The turn-on detection threshold voltage VC H ). resistance of the external control MOSFETs can be determined by the equation: R ON = V O I P/ I T (I T is the overcurrent threshold current). For example, * if the overcurrent threshold current IT is designed DESIGN GUIDE to be 5A, the turn-on resistance of the external Setting the Overcharge discharge Delay Time and Over- The overcharge delay time is set by the external capacitor CT C and the overdischarge delay time is set by the external capacitor CTD . The relationship between capacitance of the external capacitors and delay time is tabulated as below. CTC CT D(F) TOC T OD(S) 1n 21m CTC CT D(F) TOC T OD(S) 47n 617m 5n 52m 10n 132m 68n 748m 22n 253m control MOSFETs must be 30m. Users should be aware that turn-on resistance of the MOSFET changes with temperature variation due to heat dissipation. It changes with the voltage between gate and source as well. (Turn-on resistance of a MOSFET increases as the voltage between gate and source decreases). Once the turn-on resistance of the external MOSFET changes, the 33n 347m 82n 100n 1004m 1630m overcurrent threshold current will change accordingly. The delay time can also be approximately Suppressing the Ripple and Disturbance from Charger calculated by the following equations (if C T C , CTD To suppress the ripple and disturbance from 82nF) : charger, connecting R1 to R4 and C1 to C4 is TOC (mS) = 11.8 x CTC (nF) recommended. TOD (mS) = 11.8 x CTD (nF) Controlling the Charge Control MOSFET Setting the Overcurrent Delay Time 1 R5, R6, R7 and NPN transistor Q1 are used to The overcurrent delay time 1 (TO I 1 ) at 0.15V < switch VC C -VC S < 0.3V is set by the external capacitor overcharge does not occur, no current flows into CTI, while the overcurrent delay time 2 and 3 (TO I 2 OC pin and Q1 is turned off, then M2 is turned on. and TO I 3 ) is fixed by IC internal circuit.The When overcharge occurs, current flows into OC relationship between capacitance of the external pin and Q1 is turned on, which turns off M2 in turn. capacitor and delay time is tabulated as below. 1n 2.2n 3.3n 5n 6.8n 10n CTI (F) TOI(mS) 4.8 15.0 18.8 23.6 31.0 61.8 the charge control MOSFET M2. If Protection at CS Pin R8 is used for protection of IC when charger is connected in reverse. The charge detection function after overdischarge is possibly disabled Selection of External Control MOSFETs by larger value of R8. Resistance of 1K is Because the overcurrent protection voltage is recommended. preset, the threshold current for overcurrent detection is determined by the turn-on resistance 10 AIC1803 n TIMING DIAGRAM l Overcharge and Overdischarge Protection (VCS=VCC ) <TOC TOC V BAT1 V OCP V OCP - VHYS VCELL V BAT2 V BAT3 V ODR V ODP TOD <T OD VOC VOD Hi-Z Hi-Z 0V V CC 0V l Overcurrent Protection (VCELL=3.5V) >256ms <256ms VCC VCC- 0.15V VCC- 0.3V VCS VCC - 1V 0V TOI1 <TOI2 VOD <T TOI3 OI1 VCC 0V 256ms <256ms VOC Hi-Z 11 AIC1803 n PHYSICAL DIMENSIONS l 16 LEAD PLASTIC SO (150 mil) (unit: mm) D H E SYMBOL MIN MAX A 1.35 1.75 A1 0.10 0.25 B 0.33 0.51 C 0.19 0.25 D 9.80 10.00 E 3.80 4.00 e e H 5.80 6.20 L 0.40 1.27 A1 A 1.27 (TYP) B C L 12