AOZ1401DI Li+ Charger Protection IC General Description Features The AOZ1401 is an integrated Li+ charger protection IC that protects against input over-voltage, input overcurrent, and battery over-voltage conditions. When the device detects an input over-voltage condition, it disconnects output from input by turning off the internal MOSFET switch, preventing damage of the charger. When the device detects a battery over-voltage condition, it also turns off the internal MOSFET to prevent battery from being over-charged. In the case of an overcurrent condition, it limits the input current at the current limit level set by an external resistor, and if the overcurrent persists, it turns off the internal MOSFET after a blanking period. The thermal shutdown feature adds another layer of protection. Provides protection for three variables: The fault status indicator provides status information about fault conditions to the host. Available in space-saving small 8 lead 2x2 DFN The AOZ1401 is available in a 2mm x 2mm 8-pin DFN package and is rated over a -40°C to +85°C ambient temperature range. Smart Phones – Input over-voltage – User-programmable input over-current – Battery over-voltage 30V maximum input voltage Supports up to 1.5A input current High immunity against false triggering due to voltage spikes Robust against false triggering due to current transients Thermal Shutdown Status indication, fault condition Applications PDAs MP3 Players Low-Power handheld devices Bluetooth headsets Typical Application VDC 1 VIN AC Adaptor C1 1µF OUT 8 C2 1µF AOZ1401 Charger R4 100kΩ R1 47kΩ End System R2 47kΩ VBAT 6 FAULTB 4 ENB 5 ILIM GND 7 2 R3 47kΩ R5 25kΩ Rev. 3.0 December 2013 www.aosmd.com Page 1 of 14 AOZ1401DI Ordering Information Part Number Ambient Temperature Range Package Environmental AOZ1401DI -40°C to +85°C 2 x 2 DFN-8 RoHS Compliant All AOS products are offered in packages with Pb-free plating and compliant to RoHS standards. Parts marked as Green Products (with “L” suffix) use reduced levels of Halogens, and are also RoHS compliant. Please visit www.aosmd.com/media/AOSGreenPolicy.pdf for additional information. Pin Configuration VIN 1 GND 2 8 OUT 7 ILIM AOZ1401DI NC 3 6 VBAT FAULTB 4 5 ENB Top View (DFN 2x2) Pin Description Pin Name Pin Number I/O VIN 1 I GND 2 Ground terminal NC 3 These pins may have internal circuits used for test purposes. Do not make any external connections at these pins for normal operation. FAULTB 4 O Open-drain output, device status. FAULTB = LO indicates that the input FET has been turned off due to input over-voltage or input over-current conditions, or because the battery voltage is outside safe limits. Description Input power, connect to external DC supply. Connect external 1µF (minimum) to GND ENB 5 I Chip enable input. Active low. When ENB = HI, the input FET is off. Internally pulled down. VBAT 6 I Battery voltage sense input. Connect to pack positive terminal through a resistor. ILIM 7 I/O OUT 8 O Thermal PAD Rev. 3.0 December 2013 Input over-current threshold programming. Connect a resistor to GND to set the over-current threshold. Output terminal to the charging system. Connect external 1µF capacitor (minimum) to GND There is an internal electrical connection between the exposed thermal pad and the GND pin of the device. The thermal pad must be connected to the same potential as the GND pin on the printed circuit board. Do not use the thermal pad as the primary ground input for the device. GND pin must be connected to ground at all times. www.aosmd.com Page 2 of 14 AOZ1401DI Absolute Maximum Ratings(1) Parameter Pin Name Rating Input Voltage VIN (with respect to GND) –0.3V to 30V Input Voltage OUT(with respect to GND) –0.3V to 12V Input Voltage ILIM, FAULTB, ENB, VBAT (with respect to GND) –0.3V to 7V Input Current VIN 2.0A Output Current OUT 2.0A Output Sink Current FAULTB 15mA Junction Temperature, TJ –40°C to 150°C Storage Temperature, TSTG –65°C to 150°C Lead Temperature (Soldering, 10 seconds) 300°C ESD (Human Body Model) 2kV ESD (Machine Model) 200V Note: 1. Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. All voltage values are with respect to the network ground terminal unless otherwise noted. Recommended Operating Conditions Parameter Conditions VVIN VIN Voltage Range Min. Max. Units 3.3 26 V IVIN Input Current, VIN pin 1.5 A IOUT Current, OUT pin 1.5 A RILIM OCP Programming Resistor 15 90 kΩ Junction Temperature 0 125 °C TJ Rev. 3.0 December 2013 www.aosmd.com Page 3 of 14 AOZ1401DI Electrical Characteristics TA = 25°C and VIN = 5V, unless otherwise stated. Specifications in BOLD are guaranteed by design for ambient temperature range of -40°C to +85°C Symbol Parameter Test Conditions Min. Typ. Max. Units 2.6 2.7 2.8 V VIN VUVLO VHYS-UVLO TDGL(PGOOD) IDD ISTDBY Under-Voltage Lock-out, Input Power Detected Threshold ENB = LO Hysteresis on UVLO ENB = LO 260 mV Deglitch Time, Input Power Detected Status ENB = LO 8 ms Operating Current ENB = LO, No Load on OUT pin, VIN = 5.0V, RILIM = 25kΩ 400 500 µA Standby Current ENB = HI, RILIM = 25kΩ 70 95 µA 300 mV 6.00 V 1 µs INPUT TO OUTPUT CHARACTERISTICS VDO Drop-Out Voltage VIN to OUT ENB = LO, IOUT = 1A INPUT OVER-VOLTAGE PROTECTION Input Over-Voltage Protection Threshold ENB = LO Input OV Propagation Delay ENB = LO VHYS-OVP Hysteresis on OVP ENB = LO or HI 60 mV tON(OVP) Recovery Time from Input Over-voltage Condition ENB = LO 8 ms VOVP tPD(OVP) 5.67 5.85 INPUT OVER-CURRENT PROTECTION Input Over-Current Protection Threshold Range ENB = LO 300 IOCP Input Over-Current Protection Threshold ENB = LO, RILIM = 25kΩ 930 KILIM Current Limit Programming: IOCP = KILIM / RILIM tBLANK(OCP) tON(OCP) 1000 1500 mA 1070 mA 25 kΩ Blanking Time, Input Over-Current Detected ENB = LO 176 µs Recovery Time from Input Over-current Condition ENB = LO 64 ms BATTERY OVER-RANGE PROTECTION BVOVP VHYS-BOVP IVBAT TDGL(BOVP) Battery Over-Voltage Protection Threshold ENB = LO, VIN > 4.4V Hysteresis on BVOVP ENB = LO, VIN > 4.4V 270 ENB = LO 176 µs 140 °C 4.30 4.35 Input Bias Current on VBAT pin Deglitch Time, Battery Over-Voltage Detected 4.4 V mV 20 nA THERMAL PROTECTION TJ(OFF) Thermal Shutdown Temperature Rev. 3.0 December 2013 www.aosmd.com Page 4 of 14 AOZ1401DI Electrical Characteristics (Continued) TA = 25°C and VIN = 5V, unless otherwise stated. Specifications in BOLD are guaranteed by design for ambient temperature range of -40°C to +85°C Symbol TJ(OFF-HYS) Parameter Test Conditions Min. Thermal Shutdown Hysteresis Typ. Max. 20 Units °C LOGIC LEVELS ON ENB VIL Logic LOW Input Voltage 0 VIH Logic HIGH Input Voltage 1.4 0.4 V V IIL ENB = 0V 1 µA IIH ENB = 1.8V 15 µA LOGIC LEVELS ON FAULTB VOL Output LOW Voltage ISINK = 5mA 0.2 V IHI-Z Leakage Current VFAULTB = 5V 10 µA Functional Block Diagram VIN OUT UVLO Comp Driver ILIM 2.70V OCP ENB Control Logic VBAT 5.85V 4.35V Input OVP Comp Battery OVP Comp FAULTB Bias Gen Figure 1. Simplified Block Diagram Rev. 3.0 December 2013 www.aosmd.com Page 5 of 14 AOZ1401DI Functional Characteristics VIN VIN VOUT VOUT IOUT FAULTB Figure 2. Normal Power-On Showing Soft-Start, ROUT = 6.6Ω Figure 3. OVP at Power-On, VIN = 0V to 9V VIN VIN VOUT FAULTB VOUT IOUT FAULTB Figure 4. OVP Response for Input Step, VIN = 5V to 12V, Figure 5. Recovery from OVP, VIN = 7.5V to 5V VIN VIN VOUT IOUT VOUT IOUT FAULTB FAULTB Figure 6. OCP, Powering Up into a Short Circuit on OUT Pin, OCP Counter Counts to 15 Before Switching OFF the Device Rev. 3.0 December 2013 www.aosmd.com Figure 7. OCP, ROUT Switches from 6.6Ω to 3.3Ω, Shows Current Limiting and Soft-stop Page 6 of 14 AOZ1401DI Functional Characteristics (Continued) VBAT T VBAT VOUT T VOUT FAULTB FAULTB Figure 8. BAT-OVP, VVBAT Steps from 4.2V to 4.4V Figure 9. Battery OVP and Counter Typical Operating Characteristics 2.80 300 2.75 Drop-Out Voltage (V) 250 UVLO (V) 2.70 2.65 Increasing Decreasing 2.60 2.55 2.50 200 4V Vin 5V Vin 150 100 50 2.45 2.40 -50 -30 -10 10 30 50 70 90 110 0 -50 130 -30 -10 Figure 10. UVLO vs. Temperature 30 50 70 90 110 130 Figure 11. Drop-out Voltage vs. Temperature 5.80 1800 5.79 1600 5.78 Ilim(mA) 1400 Increasing Decreasing 5.77 ILim (mA) Over Voltage Protection (V) 10 Temp (°C) Temp (°C) 5.76 5.75 1200 1000 800 5.74 600 5.73 400 5.72 200 5.71 5.70 -50 0 -30 -10 10 30 50 70 90 110 130 Temp (°C) 20 40 60 80 100 RLim (KOhm) Figure 12. Over-voltage Protection vs. Temperature Rev. 3.0 December 2013 0 www.aosmd.com Figure 13. ILim vs. RLim Page 7 of 14 AOZ1401DI Typical Operating Characteristics (Continued) 4.35 Battery Over Voltage Protection (V) 1.20 Over Current Protection (A) 1.15 1.10 1.05 1.00 Over Current 0.95 0.90 0.85 0.80 0.75 0.70 -50 -30 -10 10 30 50 70 90 4.30 4.25 4.20 Increasing Decreasing 4.15 4.10 4.05 4.00 -50 110 -30 -10 Temp (°C) 30 50 70 90 110 130 Temp (°C) Figure 14. Over-current Protection vs. Temperature Figure 15. Battery Over Voltage Protection vs. Temperature 500 3.50 Leakage 450 3.00 400 2.50 350 2.00 300 Iin (uA) VBAT Leakage (nA) 10 1.50 EN = L EN = H 250 200 150 1.00 100 0.50 0.00 -50 50 0 -30 -10 10 30 50 70 90 110 130 0 10 20 30 40 Temp (°C) Vin (V) Figure 16. VBAT Leakage Current vs. Temperature Figure 17. Supply Current vs. Input Voltage Rev. 3.0 December 2013 www.aosmd.com Page 8 of 14 AOZ1401DI Flow Chart Power Down All IC functions OFF FAULTB = Hi-Z Any state If VIN <V (UVLO), go to Power Down Any state If ENB = Hi, go to Reset No VIN >V (UVLO)? Yes Reset Timers reset Counters reset FAULTB = Hi-Z FET off No ENB = Low? Yes VIN <V (OVP)? No Turn off FET FAULTB = Low No ENB = Hi? Yes Go to Reset No Yes Turn off FET FAULTB = Low Incr OCP counter I <IOCP? No Count <15 ? Yes Wait tON(OCP) Yes No ENB = Hi? Yes Go to Reset No VBAT < BATOVP? No Turn off FET FAULTB = Low Incr BAT counter Count <15 ? Yes TJ <TJ ? (OFF) No Turn off FET FAULTB = Low Yes Turn on FET FAULTB = Hi-Z Rev. 3.0 December 2013 www.aosmd.com Page 9 of 14 AOZ1401DI Theory of Operation Battery Over-voltage Protection The AOZ1401DI is an integrated Li+ charger protection IC that protects against input over-voltage, input overcurrent, and battery over-voltage conditions. The battery overvoltage threshold BVOVP is internally set to 4.35V. If the battery voltage exceeds the BVOVP threshold, the FET is turned off, and the FAULTB pin is driven low. When the device detects an input over-voltage condition, it turns off the internal MOSFET, preventing damage of the charger. FAULTB When the device detects a battery over-voltage condition, it also turns off the internal MOSFET to prevent battery from being over-charged. In the case of an over-current condition, it limits the input current at the current limit level set by an external resistor, and if the over-current persists, it turns off the internal MOSFET after a blanking period. The thermal shutdown feature adds another layer of protection. The fault status indicator provides status information about fault conditions to the host. The FAULTB pin is an open drain output that is asserted low when either an input overvoltage, input overcurrent battery overvoltage, or thermal overload condition occurs. Thermal Shut-down Protection The thermal overload protection of AOZ1401DI is engaged to protect the device from damage should the die temperature exceeds safe margins due to a short circuit, extreme loading or heating from external sources. Application Information Input Capacitor Selection The under-voltage lockout (UVLO) circuit of AOZ1401DI monitors the input voltage and prevents the output MOSFET from turning on until VIN exceeds 2.7V. Use a 1μF or larger capacitor for input bypassing. This will limit the input voltage drop during output transient conditions. 1μF capacitor should be adequate for most applications; however, higher capacitor values will further reduce the voltage drop. Place the bypass capacitor as close to the IN pins as feasibly possible. Enable Output Capacitor Selection The ENB pin is the ON/OFF control for the output switch. When the ENB pin is driven high, the internal FET is turned off. When the ENB pin is low, the FET is turned on. Use a 1μF or larger capacitor between the OUT and GND pins. The capacitance does not affect the turn on slew rate; however, a larger capacitor will make the initial turn on transient smoother. Input Overvoltage Protection Selection of R4 (RVBAT) The device continuously monitors the input voltage, the input current, and the battery voltage. If the input voltage rises above VOVP, the internal FET is turned off, removing power from the circuit. When the input voltage returns below VOVP, but above VUVLO, the FET is turned on again after a deglitch time of tON (OVP) to ensure that the input supply has stabilized. Direct-connecting battery to VBAT is not recommended. The voltage at the IN pin may appear on the VBAT pin if IC fails. Connecting the VBAT pin through R4 (RVBAT) prevents a large current from flowing into the battery in case of a failure of the IC, so choose R4 (RVBAT) value in the range 100kΩ to 470kΩ. Under-Voltage Lockout (UVLO) Selection of R3 (REN), R2 (RFAULTB), and R1 (RPU) Input Overcurrent Protection In the case of an over-current condition, AOZ1401DI limits the input current at the current limit level set by an external resistor, and if the over-current persists, it turns off the internal MOSFET after a blanking period. The overcurrent threshold is programmed by a resistor R5 (RILIM) connected from the ILIM pin to VSS. Figure 13 shows the OCP threshold as a function of R5 (RILIM), and may be approximated by the following equation: IOCP = 25 R5 (RILIM) (current in A, resistance in kΩ). Rev. 3.0 December 2013 The ENB pin can be used to enable and disable the IC. ENB pin can be tied to ground or left un-connected, permanently enabling the device, if host is not presented. If host control is required, the ENB pin should be connected to the host through as large a resistor as possible. The FAULTB pin is an open drain output that is asserted low when either an input overvoltage, input overcurrent battery overvoltage, or thermal overload condition occurs. If the application does not require monitoring of www.aosmd.com Page 10 of 14 AOZ1401DI the FAULTB pin, it can be left unconnected. But if the FAULTB pin has to be monitored, it should be pulled high externally through R1 (RPU), and connected to the host through R2 (RFAULTB) prevents damage to the host controller if the AOZ1401DI fails. Choose the resistors with high values, and values between 22kΩ and 100kΩ should be sufficient. Rev. 3.0 December 2013 PCB Layout Guidelines AOZ1401DI uses DFN 2x2 package with a thermal PAD. The thermal PAD should be thermally coupled with the PCB ground plane for good thermal performance, This will require a copper pad directly under the IC in most applications. This copper pad should be connected to the ground plane with an array of thermal vias. CIN, COUT, RILIM and RBAT should be located close to the IC. www.aosmd.com Page 11 of 14 AOZ1401DI Package Dimensions, DFN 2x2-8L B D A bbb C A B 8 b e 8 R aaa C 2x E Pin#1 Identification Option 1 E1 L 1 D1 1 a a a C 2x BOTTOM VIEW TOP VIEW 8 ccc C A C C A1 ddd C Pin#1 Identification Option 2 seating plan SIDE VIEW Chamfer 0.2x45° 1 BOTTOM VIEW RECOMMENDED LAND PATTERN 0.50 Dimensions in millimeters 0.25 0.25 0.85 0.90 1.70 0.30 1.50 UNIT: mm Symbols A A1 b c D D1 E E1 e L R aaa bbb ccc ddd Min. 0.70 0.00 0.18 1.90 1.35 1.90 0.75 0.20 Nom. 0.75 0.02 0.25 0.20 REF 2.00 1.50 2.00 0.90 0.50 BSC 0.30 0.20 0.15 0.10 0.10 0.08 Max. 0.80 0.05 0.30 2.10 1.60 2.10 1.00 0.40 Dimensions in inches Symbols A A1 b c D D1 E E1 e L R aaa bbb ccc ddd Min. 0.028 0.000 0.007 Nom. Max. 0.030 0.031 0.001 0.002 0.010 0.012 0.008 REF 0.075 0.079 0.083 0.053 0.059 0.063 0.075 0.079 0.083 0.030 0.035 0.039 0.020 BSC 0.008 0.012 0.016 0.008 0.006 0.004 0.004 0.003 Notes: 1. Dimensioning and tolerancing conform to ASME Y14.5M-1994. 2. Controlling dimension is in millimeter, converted inch dimensions are not necessarily exact. 3. Dimension b applies to matellized terminal and is measured between 0.10mm and 0.30mm from the terminal tip. If the terminal has the optional radius on the other end of the terminal, the dimension b should not be measured in that radius area. 4. Coplanarity ddd applies to the terminals and all other bottom surface metallization. Rev. 3.0 December 2013 www.aosmd.com Page 12 of 14 AOZ1401DI Tape and Reel Dimensions, DFN 2x2-8L Carrier Tape SECTION A--A FEEDING DIRECTION UNIT: MM Package A0 B0 DFN 2x2 2.25 ±0.05 2.25 ±0.05 K0 D0 D1 E E1 1.00 1.50 1.00 8.00 1.75 ±0.05 ±0.10 ±0.25 ±0.30 ±0.10 -0.10 E2 P0 3.50 4.00 ±0.05 ±0.10 P1 P2 4.00 2.00 ±0.10 ±0.05 T 0.254 ±0.02 Reel UNIT: MM Tape Size 8mm Reel Size Ø177.8 M N W1 W2 H S K Ø177.8 MAX. 53.6 MIN. 8.4 +2.5 -0.0 14.4 MAX. 13.0 +0.5 -0.3 1.5 MIN. 10.1 MIN. Leader/Trailer and Orientation Rev. 3.0 December 2013 www.aosmd.com Page 13 of 14 AOZ1401DI Part Marking AOZ1401DI (2 x 2 DFN) A F1 A 9B12 Part Number Code Underscore Denotes Green Product Assembly Location Code Option Code Assembly Lot Code Year Code Week Code LEGAL DISCLAIMER Alpha and Omega Semiconductor makes no representations or warranties with respect to the accuracy or completeness of the information provided herein and takes no liabilities for the consequences of use of such information or any product described herein. Alpha and Omega Semiconductor reserves the right to make changes to such information at any time without further notice. This document does not constitute the grant of any intellectual property rights or representation of non-infringement of any third party’s intellectual property rights. LIFE SUPPORT POLICY ALPHA AND OMEGA SEMICONDUCTOR PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. Rev. 3.0 December 2013 2. A critical component in any component of a life support, device, or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.aosmd.com Page 14 of 14