IGNS W DES E N R O DF ART ME N D E MENT P E M C O A C L E EP Data D RSheet N OT R MENDE 8XZ-T RECOM ISL9211BIRU5 ISL9211 January 13, 2009 Charging System Safety Circuit Features The ISL9211 is an integrated circuit (IC) optimized to provide a redundant safety protection to a Li-ion battery charging system. The IC monitors the input voltage, the battery voltage, and the charge current. When any of the three parameters exceeds its limit, the IC turns off an internal N-channel MOSFET to remove the power from the charging system to the battery. In addition to the above protected parameters, the IC also monitors its own internal temperature and turns off the N-channel MOSFET when the temperature exceeds +150°C. Together with the battery charger IC and the protection module in a battery pack, the charging system using the ISL9211 has triple-level protection and is two-fault tolerant. • 24V Max Input Voltage The IC is designed to turn on the internal NFET slowly to avoid inrush current at power up but will turn off the NFET quickly when the input is overvoltage in order to remove the power before any damage occurs. The ISL9211 has a logic flag output to indicate a fault condition. • Pb-Free (RoHS Compliant) Typical Application Circuit • PDAs and Smart Phones INPUT VIN C2 ISL6292 BATTERY CHARGER VB GND FAULT • Fully Integrated Protection Circuit for Three Protected Variables • High Accuracy Protection Thresholds • User Programmable Overcurrent Protection Threshold • Responds To Input Overvoltage in Less Than 1µs • High Immunity of False Triggering Under Transients • Fault Indication for Various Fault Occurrence • Easy to Use Applications • Cell Phones • Digital Still Cameras • Technical Brief TB363 “Guidelines for Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs)” RVB RILIM • Desktop Chargers Related Literature ISL9211 ILIM • Supports Up To 1.5A Input Current • Portable Instruments OUT C1 FN6658.4 BATTERY PACK • Technical Brief TB379 “Thermal Characterization of Packaged Semiconductor Devices” • Technical Brief TB389 “PCB Land Pattern Design and Surface Mount Guidelines for QFN Packages” Ordering Information PART NUMBER PART MARKING Pinout TEMP RANGE (°C) ISL9211IRU58XZ-T* 15X -40 to +85 8 Ld µTDFN L8.2x2 ISL9211IRU68XZ-T* 16X -40 to +85 8 Ld µTDFN L8.2x2 *Please refer to TB347 for details on reel specifications. NOTE: These Intersil Pb-free plastic packaged products employ special Pb-free material sets; molding compounds/die attach materials and NiPdAu plate - e4 termination finish, which is RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020. 1 ISL9211 (8 LD 2x2 ΜTDFN) TOP VIEW PACKAGE PKG. (Pb-Free) DWG. # VIN 1 8 OUT GND 2 7 ILIM NC 3 6 VB FAULT 4 5 GND CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2008, 2009, 2015. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. ISL9211 Absolute Maximum Ratings Thermal Information Supply Voltage (VIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 26V Output and VB Pin (OUT, VB) (Note 1) . . . . . . . . . . . . . . -0.3V to 8V Other Pins (ILIM, FAULT). . . . . . . . . . . . . . . . . . . . . . . -0.3V to 5.5V Thermal Resistance (Typical, Note 2) JA (°C/W) 8 Ld 2x2 µTDFN Package . . . . . . . . . . 120 Maximum Junction Temperature (Plastic Package) . . . . . . . +150°C Maximum Storage Temperature Range . . . . . . . . . .-65°C to +150°C Pb-Free Reflow Profile. . . . . . . . . . . . . . . . . . . . . . . . .see link below http://www.intersil.com/pbfree/Pb-FreeReflow.asp Recommended Operating Conditions Ambient Temperature Range . . . . . . . . . . . . . . . . . . .-40°C to +85°C Supply Voltage, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3V to 24V Operating Current Range. . . . . . . . . . . . . . . . . . . . . . . . . 0A to 1.5A CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and result in failures not covered by warranty. NOTES: 1. The maximum voltage rating for the VB pin under continuous operating conditions is 5.5V. All other pins are allowed to operate continuously at the absolute maximum ratings. 2. JA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See Tech Brief TB379. Electrical Specifications Typical values are tested at VIN = 5V and +25°C Ambient Temperature, maximum and minimum values are established over the recommended operating conditions; Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits established by characterization and are not production tested. PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNITS Rising - - 2.47 V Falling POWER-ON RESET Rising VIN Threshold VPOR VIN Bias Current 2.20 - - V IVIN RILIM = 24.9k - - 1000 µA VOVP ISL9211IRU58 5.6 5.8 6.0 V ISL9211IRU68 6.6 6.8 6.95 V ISL9211IRU58 5.55 - - V ISL9211IRU68 6.55 - - V - - 1 µs PROTECTIONS Input Overvoltage Protection Input OVP Falling Threshold Input OVP Response Time (Note 3) Overcurrent Protection IOCP 0.93 1.0 1.07 A Overcurrent Protection Blanking Time BTOCP VVB = 3V, RILIM = 24.9k - 180 - µs Battery Overvoltage Protection Threshold VBOVP 4.25 4.34 4.40 V - 30 50 mV - 180 - µs - - 20 nA Over-Temperature Protection Rising Threshold - 150 - °C Over-Temperature Protection Falling Threshold - 110 - °C - 0.4 0.8 V - - 1.5 µA - 170 280 m Battery OVP Threshold Hysteresis Battery OVP Blanking Time BTBOVP VVB = 4.34V VB Pin Leakage Current LOGIC FAULT Output Logic Low Sink 5mA current FAULT Output Logic High Leakage Current POWER MOSFET On-Resistance (Note 3) rDS(ON) Measured at 200mA NOTE: 3. Limits should be considered typical and are not production tested. 2 FN6658.4 January 13, 2009 ISL9211 Pin Descriptions Typical Application VIN (Pin 1) The input power source. The VIN can withstand 24V input. VIN INPUT OUT ISL6292 BATTERY CHARGER GND (Pins 2, 5) C1 System ground reference. C2 NC (Pin 3) ISL9211 No connection and must be left floating. VB ILIM RVB FAULT (Pin 4) RILIM FAULT is an open-drain logic output that turns LOW when any protection event occurs. FAULT GND BATTERY PACK VB (Pin 6) Battery voltage monitoring input. This pin is connected to the battery pack positive terminal via an isolation resistor. PART ILIM (Pin 7) Overcurrent protection threshold setting pin. Connect a resistor between this pin and GND to set the OCP threshold. RILIM 24.9k RVB 200k to 1M C1, C2 OUT (Pin 8) DESCRIPTION 1µF/25V X5R ceramic capacitor Output pin. Block Diagram OUT VIN INPUT ISL6292 BATTERY CHARGER Q1 Q2 POR PRE-REG REF FET DRIVER R1 LOGIC 1.2V RILIM CP2 EA VB CP3 RVB R3 Q4 FAULT ILIM 0.8V CP1 R2 Q3 R4 GND FIGURE 1. BLOCK DIAGRAM 3 FN6658.4 January 13, 2009 ISL9211 Typical Operating Performance The test conditions for the Typical Operating Performance are: VIN = 5V, TA = +25°C, RILIM = 24.9k, RVB = 200k, Unless Otherwise Noted. VIN(2V/div) VIN(2V/div) OUT(2V/div) OUT(2V/div) Load Current(200mA/div) Fault(5V/div) TIME - 4ms/div FIGURE 2. CAPTURED WAVEFORMS FOR POWER-UP. THE OUTPUT IS LOADED WITH A 10 RESISTOR VIN(2V/div) OUT(2V/div) Fault(5V/div) TIME - 2s/div FIGURE 4. CAPTURED WAVEFORMS WHEN THE INPUT GRADUALLY RISES TO THE INPUT OVERVOLTAGE THRESHOLD TIME - 20µs/div FIGURE 3. CAPTURED WAVEFORMS WHEN THE INPUT VOLTAGE STEPS FROM 5.5V TO 9.5V VIN(2V/div) OUT(2V/div) Fault(5V/div) TIME - 4ms/div FIGURE 5. TRANSIENT WHEN THE INPUT VOLTAGE STEPS FROM 6.5V TO 5.5V VIN(1V/div) VIN(5V/div) VB(1V/div) OUT(2V/div) Fault(2V/div) TIME - 40µs/div FIGURE 6. TRANSIENT WAVEFORMS WHEN INPUT STEPS FROM ZERO TO 9V 4 OUT(1V/div) Fault(2V/div) TIME - 20s/div FIGURE 7. BATTERY OVERVOLTAGE PROTECTION. THE IC IS LATCHED OFF AFTER 16 COUNTS OF PROTECTION. VB VOLTAGE VARIES BETWEEN 4.3V TO 4.5V FN6658.4 January 13, 2009 ISL9211 Typical Operating Performance The test conditions for the Typical Operating Performance are: VIN = 5V, TA = +25°C, RILIM = 24.9k, RVB = 200k, Unless Otherwise Noted. (Continued) VIN(2V/div) VIN(2V/div) Load Current(500mA/div) Load Current(500mA/div) OUT(2V/div) OUT(2V/div) Fault(2V/div) Fault(2V/div) TIME - 1ms/div TIME - 40ms/div FIGURE 9. ZOOMED-IN VIEW OF FIGURE 8 FIGURE 8. POWER-UP WAVEFORMS WHEN OUTPUT IS SHORT-CIRCUITED 5.85 2.52 2.48 5.80 RISING THRESHOLD RISING THRESHOLD 2.40 VOVP (V) VPOR (V) 2.44 2.36 FALLING THRESHOLD 2.32 2.28 5.75 FALLING THRESHOLD 5.70 5.65 2.24 2.20 -50 -30 -10 10 30 50 70 5.60 -50 90 -30 -10 TEMPERATURE (°C) ILIM PIN VOLTAGE (V) OVERCURRENT PROTECTION (A) 1.00 0.99 0.98 3.0V 0.984 0.982 0.980 0.978 0.976 0.974 0.96 0.95 -50 90 0.986 1.01 0.97 70 0.988 4.3V 1.02 50 FIGURE 11. INPUT OVERVOTLAGE PROTECTION vs TEMPERATURE 5.0V 1.03 30 TEMPERATURE (°C) FIGURE 10. VPOR vs TEMPERATURE 1.04 10 -30 -10 10 30 50 70 90 110 130 TEMPERATURE (°C) FIGURE 12. OVERCURRENT PROTECTION vs TEMPERATURE AT VARIOUS INPUT VOLTAGES 5 0.972 -50 -30 -10 10 30 50 70 90 110 130 TEMPERATURE (°C) FIGURE 13. ILIM PIN VOLTAGE vs TEMPERATURE FN6658.4 January 13, 2009 ISL9211 Typical Operating Performance The test conditions for the Typical Operating Performance are: VIN = 5V, TA = +25°C, RILIM = 24.9k, RVB = 200k, Unless Otherwise Noted. (Continued) 350 3.0V 300 4.3V rDS(ON) (m) 250 200 150 5.0V 100 50 0 -50 -30 -10 10 30 50 70 90 110 130 TEMPERATURE (°C) FIGURE 14. ON-RESISTANCE vs TEMPERATURE AT DIFFERENT INPUT VOLTAGES Theory of Operation The ISL9211 is an integrated circuit (IC) optimized to provide a redundant safety protection to a Li-ion battery from charging system failures. The IC monitors the input voltage, the battery voltage, and the charge current. When any of the above three parameters exceeds its limit, the IC turns off an internal N-channel MOSFET to remove the power from the charging system. In addition to the above protected parameters, the IC also monitors its own internal temperature and turns off the N-channel MOSFET when the temperature exceeds +150°C. Together with the battery charger IC and the protection module in a battery pack, the charging system has triple-level protection from overcharging the Li-ion battery and is two-fault tolerant. The ISL9211 protects up to 26V input voltage. Power-Up The ISL9211 has a power-on reset (POR) threshold of 2.47V (max). Before the input voltage reaches the POR threshold, the internal power NFET is off. Approximately 10ms after the input voltage exceeds the POR threshold, the IC resets itself and begins the soft-start. The 10ms delay allows any transients at the input during a hot insertion of the power supply to settle down before the IC starts to operate. The soft-start slowly turns on the power NFET to reduce the inrush current as well as the input voltage drop during the transition. The power-up sequence is illustrated in Figure 2. Input Overvoltage Protection (OVP) The input voltage is monitored by the comparator CP1 in the Block Diagram (Figure 1). CP1 has an accurate reference of 1.2V from the bandgap reference. The OVP threshold is set by the resistive divider consisting of R1 and R2. When the input voltage exceeds the threshold, the CP1 outputs a logic signal to turn off the power NFET within 1µs (see Figure 3) to prevent the high input voltage from damaging the electronics in the handheld system. The hysteresis for the input OVP threshold is given in the “Electrical Specifications” table on 6 page 2. When the input overvoltage condition is removed, the ISL9211 re-enables the output by running through the soft-start, as shown in Figure 5. Because of the 10ms second delay before the soft-start, the output is never enabled if the input rises above the OVP threshold quickly, as shown in Figure 6. Battery Overvoltage Protection The battery voltage OVP is realized with the VB pin. The comparator CP3, as shown in Figure 1, monitors the VB pin and issues an overvoltage signal when the battery voltage exceeds the 4.34V battery OVP threshold. The threshold has 30mV built-in hysteresis. The comparator CP3 has a built-in 180µs blanking time to prevent any transient voltage from triggering the OVP. If the OVP situation still exists after the blanking time, the power NFET is turned off. The control logic contains a 4-bit binary counter that if the battery overvoltage event occurs 16x, the power NFET is turned off permanently, as shown in Figure 7. Recycling the input power will reset the counter and restart the ISL9211. The resistor between the VB pin and the battery, RVB, as shown in the “Typical Application Circuit” on page 1, is an important component. This resistor provides a current limit in case the VB pin is shorted to the input voltage under a failure mode. The VB pin leakage current under normal operation is negligible to allow a resistance of 200k to 1M be used. Overcurrent Protection (OCP) The current in the power NFET is limited to prevent charging the battery with an excessive current. The current is sensed using the voltage drop across the power FET after it is turned on. The reference of the OCP is generated using a sensing FET Q2 (Mirror to Q1), as shown in Figure 1. The current in the sensing FET is forced to match the value programmed by the ILIM pin. The size of the power FET Q1 is 31,250x the size of the sensing FET. Therefore, when the current in the power FET is 31,250x the current in the sensing FET, the drain voltage of the power FET falls below FN6658.4 January 13, 2009 ISL9211 The OCP threshold can be calculated using Equation 1: 0.8V 25000 I LIM = --------------- 31250 = ---------------R ILIM R ILIM (EQ. 1) where the 0.8V is the regulated voltage at the ILIM pin. The OCP comparator CP2 has a built-in 170µs delay to prevent false triggering by transient signals. The OCP function also has a 4-bit binary counter that accumulates during an OCP event. When the total count reaches 8, the power NFET is turned off permanently until the input power is recycled or the enable pin is toggled. Figures 8 and 9 illustrate the waveforms during the power-up when the output is shorted to ground. Internal Over-Temperature Protection The ISL9211 monitors its own internal temperature to prevent thermal failures. When the internal temperature reaches +150°C, the IC turns off the N-channel power MOSFET. The IC does not resume operation until the internal temperature drops below +110°C. Fault Indication Output The FAULT pin is an open-drain output that indicates a LOW signal when any of the three fault events happens. This provides a signal to the microprocessor to take further action to enhance the safety of the charging system. Applications Information The ISL9211 is designed to meet the “Lithium-Safe” criteria when operating together with a qualified Li-ion battery charger. The “Lithium-Safe” criteria requires the charger output to fall within the green region shown in Figure 15 under normal operating conditions and NOT to fall in the red region when there is a single fault in the charging system. Taking into account the safety circuit in a Li-ion battery pack, the charging system is allowed to have two faults without creating hazardous conditions for the battery cell. The output of the Li-ion charger, such as the ISL6292, ISL6292C, has a typical I-V curve shown with the blue lines under normal operation, which is within the green region. The function of the ISL9211 is to add a redundant protection layer such that, under any single fault condition, the charging system output does not exceed the I-V limits shown with the red lines. As a result, the charging system adopting the ISL9211 and the ISL6292, ISL6292C chip set can easily pass the “LithiumSafe” criteria test procedures. The ISL9211 is a simple device that requires only three external components, in addition to the ISL6292 charger circuit, to meet the “Lithium-Safe” criteria, as shown in the “Typical Application Circuit” on page 1. The selection of the current limit resistor RILIM is given in “Overcurrent Protection (OCP)” on page 6. 7 RVB Selection The RVB prevents a large current from the VB pin to the battery terminal, in case the ISL9211 fails. The recommended value should be between 200k to 1M. With 200k resistance, the worst case current flowing from the VB pin to the charger output is shown in Equation 2, assuming the VB pin voltage is 24V under a failure mode and the battery voltage is 4.2V. 24V – 4.2V 200k = 99A (EQ. 2) Such a small current can be easily absorbed by the bias current of other components in the handheld system. Increasing the RVB value reduces the worst case current, but at the same time increases the error for the 4.34V battery OVP threshold. The error of the battery OVP threshold is the original accuracy at the VB pin given in the “Electrical Specifications” table on page 2 plus the voltage built across the RVB by the VB pin leakage current. The VB pin leakage current is less than 20nA, as given in the “Electrical Specifications” table. With the 200k resistor, the worst-case additional error is 4mV and with a 1M resistor, the worst-case additional error is 20mV. 1000 ISL9211 LIMITS CHARGE CURRENT (mA) that of the sensing FET. The comparator CP2 then outputs a signal to turn off the power FET. ISL6292C LIMITS 0 1 2 3 4 5 6 BATTERY VOLTAGE (V) FIGURE 15. LITHIUM-SAFE OPERATING REGIONS Capacitor Selection The input capacitor (C1 in the “Typical Application Circuit” on page 1) is for decoupling. Higher value reduces the voltage drop or the overshoot during transients. Two scenarios can cause the input voltage overshoot. The first one is when the AC adapter is inserted live (hot insertion) and the second one is when the current in the power NFET of the ISL9211 has a step-down change. Figure 16 shows an equivalent circuit for the ISL9211 input. The cable between the AC/DC converter output and the handheld system input has a parasitic inductor. The parasitic resistor is the lumped sum of various components, such as the cable, the adapter output capacitor ESR, the connector contact resistance, and so on. FN6658.4 January 13, 2009 ISL9211 C1 L R AC/DC ADAPTER C2 ISL9211 CABLE HANDHELD SYSTEM FIGURE 16. EQUIVALENT CIRCUIT FOR THE ISL9211 INPUT During the load current step-down transient, the energy stored in the parasitic inductor is used to charge the input decoupling capacitor C2. The ISL9211 is designed to turn off the power NFET slowly during the OCP and the battery OVP event. Because of such design, the input overshoot during those events is not significant. During an input OVP, however, the NFET is turned in less than 1µs and can lead to significant overshoot. Higher capacitance reduces the overshoot. The overshoot caused by a hot insertion is not very dependent on the decoupling capacitance value. Especially when ceramic type capacitors are used for decoupling. In theory, the over-shoot can rise up to twice of the DC output voltage of the AC adapter. The actual peak voltage is dependent on the damping factor that is mainly determined by the parasitic resistance (R in Figure 16). In practice, the input decoupling capacitor is recommended to use a 25V, X5R dielectric ceramic capacitor with a value between 0.1µF to 1µF. The output of the ISL9211 and the input of the charging circuit typically share one decoupling capacitor. The selection of that capacitor is mainly determined by the requirement of the charging circuit. When using the ISL6292 family chargers, a 1µF, 6.3V, X5R capacitor is recommended. Layout Recommendation The ISL9211 uses a 2x2 DFN package. Use some copper on the component layer if possible to improve the thermal performance if possible. All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9001 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 8 FN6658.4 January 13, 2009 ISL9211 Package Outline Drawing L8.2x2 8 Lead Ultra Thin Dual Flat No-Lead COL Plastic Package (UTDFN COL) Rev 3, 11/07 2X 1.5 2.00 A 6 PIN 1 INDEX AREA PIN #1 INDEX AREA 6 B 6X 0.50 1 4 7X 0.4 ± 0.1 1X 0.5 ±0.1 2.00 (4X) 0.15 8 5 TOP VIEW 0.10 M C A B 4 0.25 +0.05 / -0.07 BOTTOM VIEW ( 8X 0 . 25 ) SEE DETAIL "X" ( 1X 0 .70 ) 0 . 55 MAX 0.10 C C BASE PLANE SEATING PLANE 0.08 C (1.8 ) SIDE VIEW C ( 7X 0 . 60 ) 0 . 2 REF 0 . 00 MIN. 0 . 05 MAX. ( 6X 0 . 5 ) DETAIL "X" TYPICAL RECOMMENDED LAND PATTERN NOTES: 1. Dimensions are in millimeters. Dimensions in ( ) for Reference Only. 2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994. 3. Unless otherwise specified, tolerance : Decimal ± 0.05 4. Dimension b applies to the metallized terminal and is measured between 0.15mm and 0.30mm from the terminal tip. 5. Tiebar shown (if present) is a non-functional feature. 6. The configuration of the pin #1 identifier is optional, but must be located within the zone indicated. The pin #1 identifier may be either a mold or mark feature. 9 FN6658.4 January 13, 2009