AOZ2261QI-11 28V/8A Synchronous EZBuckTM Regulator General Description Features The AOZ2261QI-11 is a high-efficiency, easy-to-use DC/ DC synchronous buck regulator that operates up to 28V. The device is capable of supplying 8A of continuous output current with an output voltage adjustable down to 0.8V 1%. Wide input voltage range A proprietary constant on-time PWM control with input feed-forward results in ultra-fast transient response while maintaining relatively constant switching frequency over the entire input voltage range. The on time can be externally programmed up to 2.6uS. - 2.7V to 28V 8A continuous output current Output voltage adjustable down to 0.8V (1.0%) Low RDS(ON) internal NFETs - 26m high-side - 12m low-side Constant On-Time with input feed-forward Programmable on-time up to 2.6s The device features multiple protection functions such as VCC under-voltage lockout, cycle-by-cycle current limit, output over-voltage protection, short-circuit protection, and thermal shutdown. Selectable PFM light load operation The AOZ2261QI-11 is available in a 4mmx4mm QFN22L package and is rated over a -40C to +85C ambient temperature range. Power Good output Ceramic capacitor stable Adjustable soft start Ripple reduction Integrated bootstrap diode Cycle-by-cycle current limit Short-circuit protection Over-voltage protection Efficiency Thermal shutdown Thermally enhanced 4mm x 4mm QFN-22L package Efficiency vs. Load Current 100 Efficiency (%) Applications FSW = 450kHz VOUT = 1.05V 95 Portable computers Compact desktop PCs 90 Servers 85 Graphics cards Set-top boxes 80 6.0V 8.4V 12.0V 19.5V 75 LCD TVs Cable modems 70 0 1 2 3 4 5 Output Current (A) Rev. 0.1 May 2016 6 7 8 Point-of-load DC/DC converters Telecom/Networking/Datacom equipment www.aosmd.com Page 1 of 16 AOZ2261QI-11 Typical Application RTON TON BST 5V VCC R3 100k Power Good C4 4.7F Input 2.7V to 28V IN C2 22F C5 0.1F AOZ2261QI-11 PGOOD Off On Output 1.05V, 8A LX L1 1H EN R2 FB PFM C3 88F R1 AGND SS CSS PGND Power Ground Analog Ground Recommended Start-Up Sequence VIN 5V VCC 5V EN 50s Ordering Information Part Number Ambient Temperature Range Package Environmental AOZ2261QI-11 -40C to +85C 22-Pin 4mm x 4mm QFN Green Product AOS Green Products use reduced levels of Halogens, and are also RoHS compliant. Please visit www.aosmd.com/media/AOSGreenPolicy.pdf for additional information. Rev. 0.1 May 2016 www.aosmd.com Page 2 of 16 AOZ2261QI-11 Option Table All Protection Ripple Reduction Max. On-Time Part Number Auto Restart Latch Yes V V V AOZ2261QI-10 No 2.6s 1.3s V AOZ2261QI-11 V AOZ2261QI-12 V V V AOZ2261QI-13 V V AOZ2261QI-14 V V AOZ2261QI-15 V V AOZ2261QI-16 V V AOZ2261QI-17 V V V V V V V V SS VCC BST PGND LX Pin Configuration 22 21 20 19 18 PGOOD 1 17 LX EN 2 16 LX 15 PGND PFM 3 LX IN 5 13 PGND TON 6 12 PGND 7 8 9 10 11 LX FB LX PGND IN 14 IN 4 IN AGND 22-Pin 4mm x 4mm QFN (Top View) Rev. 0.1 May 2016 www.aosmd.com Page 3 of 16 AOZ2261QI-11 Pin Description Pin Number Pin Name Pin Function 1 PGOOD Power Good Signal Output. PGOOD is an open-drain output used to indicate the status of the output voltage. It is internally pulled low when the output voltage is 15% lower than the nominal regulation voltage for or 20% higher than the nominal regulation voltage. PGOOD is pulled low during soft-start and shut down. 2 EN 3 PFM 4 AGND 5 FB 6 TON 7, 8, 9 IN 12, 13, 14, 15, 19 PGND Power Ground. 10, 11, 16, 17, 18 LX Switching Node. 20 BST Bootstrap Capacitor Connection. The AOZ2261QI-11 includes an internal bootstrap diode. Connect an external capacitor between BST and LX as shown in the Typical Application diagram. 21 VCC Supply Input for analog functions. Bypass VCC to AGND with a 1F~10F ceramic capacitor. Place the capacitor close to VCC pin. 22 SS Soft-Start Time Setting Pin. Connect a capacitor between SS and AGND to set the soft-start time. Rev. 0.1 May 2016 Enable Input. The AOZ2261QI-11 is enabled when EN is pulled high. The device shuts down when EN is pulled low. PFM Selection Input. Connect PFM pin to VCC for forced PWM operation. Connect PFM pin to ground for PFM operation to improve light load efficiency. Analog Ground. Feedback Input. Adjust the output voltage with a resistive voltage-divider between the regulator's output and AGND. On-Time Setting Input. Connect a resistor between VIN and TON to set the on time. Supply Input. IN is the regulator input. All IN pins must be connected together. www.aosmd.com Page 4 of 16 AOZ2261QI-11 Absolute Maximum Ratings Maximum Operating Ratings Exceeding the Absolute Maximum Ratings may damage the device. Parameter Rating Parameter IN, TON to AGND -0.3V to 30V LX to AGND(2) -0.3V to 30V BST to AGND -0.3V to 36V SS, PGOOD, FB, EN, VCC, PFM to AGND +150C Storage Temperature (TS) -65C to +150C (1) 2.7V to 28V Output Voltage Range 0.8V to 0.85*VIN Ambient Temperature (TA) -40C to +85C Package Thermal Resistance (JA) -0.3V to +0.3V Junction Temperature (TJ) Rating Supply Voltage (VIN) -0.3V to 6V PGND to AGND ESD Rating The device is not guaranteed to operate beyond the Maximum Operating Ratings. 40C/W 2kV Note: 1. Devices are inherently ESD sensitive, handling precautions are required. Human body model rating: 1.5k in series with 100pF. 2. LX to PGND Transient (t<20ns) ------ -7V to VIN + 7V. Electrical Characteristics TA = 25C, VIN = 12V, VCC = 5V, EN = 5V, unless otherwise specified. Specifications in BOLD indicate a temperature range of -40C to +85C. Symbol VIN Parameter Conditions IN Supply Voltage Min. Typ. 2.7 Max Units 28 V VCC rising VCC falling 4.2 3.9 V V Quiescent Supply Current of VCC IOUT = 0A, VEN > 2V, PFM mode 0.15 mA IOFF Shutdown Supply Current VEN = 0V VFB Feedback Voltage TA = 25C TA = 0C to 85C VUVLO Under-Voltage Lockout Threshold Iq IFB 0.792 0.788 1 20 A 0.800 0.800 0.808 0.812 V V Load Regulation 0.5 % Line Regulation 1 % FB Input Bias Current 200 nA 0.5 V V Enable VEN EN Input Threshold VEN_HYS EN Input Hysteresis Off threshold On threshold 1.6 100 mV PFM Control VPFM PFM Input Threshold VPFMHYS PFM Input Hysteresis PFM Mode threshold Force PWM threshold 0.5 2.5 V V 100 mV 200 ns 100 ns Modulator TON On Time RTON = 100k, VIN = 12V TON_MIN Minimum On Time TON_MAX Maximum On Time 2.6 s TOFF_MIN Minimum Off Time 300 ns Rev. 0.1 May 2016 www.aosmd.com Page 5 of 16 AOZ2261QI-11 Electrical Characteristics (Continued) TA = 25C, VIN = 12V, VCC = 5V, EN = 5V, unless otherwise specified. Specifications in BOLD indicate a temperature range of -40C to +85C. Symbol Parameter Conditions Min. Typ. Max Units 7 11 15 A 0.5 V 1 A Soft-Start ISS_OUT SS Source Current VSS = 0V CSS = 0.001F to 0.1F Power Good Signal VPG_LOW PGOOD Low Voltage IOL = 1mA PGOOD Leakage Current VPGH PGOOD Threshold (Low Level to High Level) FB rising 90 % VPGL PGOOD Threshold (High Level to Low Level) FB rising FB falling 120 85 % % 5 % 70 % 32 s FB rising 120 % High-Side NFET On-Resistance VIN = 12V, VCC = 5V 26 m High-Side NFET Leakage VEN = 0V, VLX = 0V Low-Side NFET On-Resistance VLX = 12V, VCC = 5V Low-Side NFET Leakage VEN = 0V PGOOD Threshold Hysteresis Under Voltage and Over Voltage Protection VPL Under Voltage Threshold TPL Under Voltage Delay Time VPH Over Voltage Threshold FB falling Power Stage Output RDS(ON) RDS(ON) 10 12 A m 10 A Over-current and Thermal Protection ILIM Current Limit VCC = 5V Thermal Shutdown Threshold TJ rising TJ falling Rev. 0.1 May 2016 www.aosmd.com 12 A 150 100 C C Page 6 of 16 AOZ2261QI-11 Functional Block Diagram BST IN PGood VCC EN UVLO Reference & Bias TOFF_MIN Q Timer Error Comp 0.8V SS ISENCE (AC) FB PG Logic S Q R FB Decode LX ILIM Comp ILIM Current Information Processing ISENSE OTP ISENSE ISENSE (AC) Vcc TON Q Timer PFM TON EN TON Generator Light Load Threshold Light Load Comp ISENSE PGND Rev. 0.1 May 2016 www.aosmd.com AGND Page 7 of 16 AOZ2261QI-11 Typical Performance Characteristics Circuit of Typical Application. TA = 25C, VIN = 19V, VOUT = 1.05V, fs = 500kHz unless otherwise specified. Load Transient 0A to 8A Normal Operation VLX 10V/div ILX 5A/div ILX 5A/div Vo ripple 50mV/div Vo ripple 10mV/div 5s/div 500s/div Full Load Start-up Short Circuit Protection VLX 20V/div VLX 20V/div EN 5V/div lLX 5A/div ILX 10A/div Vo 1V/div Vo 500mV/div 1ms/div Rev. 0.1 May 2016 20s/div www.aosmd.com Page 8 of 16 AOZ2261QI-11 Detailed Description The AOZ2261QI-11 is a high-efficiency, easy-to-use, synchronous buck regulator optimized for notebook computers. The regulator is capable of supplying 8A of continuous output current with an output voltage adjustable down to 0.8V. The programmable on-time from 100nS to 1.3uS enables optimizing the configuration for PCB area and efficiency. The input voltage of AOZ2261QI-11 can be as low as 2.7V. The highest input voltage of AOZ2261QI-11 can be 28V. Constant on-time PWM with input feed-forward control scheme results in ultra-fast transient response while maintaining relatively constant switching frequency over the entire input range. True AC current mode control scheme guarantees the regulator can be stable with ceramics output capacitor. The switching frequency can be externally programmed. Protection features include VCC under-voltage lockout, current limit, output over voltage and under voltage protection, short-circuit protection, and thermal shutdown. The AOZ2261QI-11 is available in 22-pin 4mmx4mm QFN package. Constant-On-Time PWM Control with Input Feed-Forward The control algorithm of AOZ2261QI-11 is constant-ontime PWM Control with input feed-forward. The simplified control schematic is shown in Figure 2. The high-side switch on-time is determined solely by a one-shot whose pulse width can be programmed by one external resistor and is inversely proportional to input voltage (IN). The one-shot is triggered when the internal 0.8V is higher than the combined information of FB voltage and the AC current information of inductor, which is processed and obtained through the sensed lower-side MOSFET current once it turns-on. The added AC current information can help the stability of constant-on time control even with pure ceramic output capacitors, which have very low ESR. The AC current information has no DC offset, which does not cause offset with output load change, which is fundamentally different from other V2 constant-on time control schemes. IN PWM - Programmable One-Shot Comp + Enable and Soft Start The AOZ2261QI-11 has external soft start feature to limit in-rush current and ensure the output voltage ramps up smoothly to regulation voltage. A soft start process begins when VCC rises to 4.5V and voltage on EN pin is HIGH. An internal current source charges the external soft-start capacitor; the FB voltage follows the voltage of soft-start pin (VSS) when it is lower than 0.8V. When VSS is higher than 0.8V, the FB voltage is regulated by internal precise band-gap voltage (0.8V). When VSS is higher than 3.3V, the PGOOD signal is high. The softstart time for PGOOD can be calculated by the following formula: TSS(s) = 330 x CSS(nF) If CSS is 1nF, the soft-start time will be 330u second; if CSS is 10nF, the soft-start time will be 3.3m second. FB Voltage/ AC Current Information 0.8V Figure 2. Simplified Control Schematic of AOZ2261QI-11 The constant-on-time PWM control architecture is a pseudo-fixed frequency with input voltage feed-forward. The internal circuit of AOZ2261QI-11 sets the on-time of high-side switch inversely proportional to the IN. R TON T ON ------------------------V IN V (1) To achieve the flux balance of inductor, the buck converter has the equation: V OUT F SW = --------------------------V IN T ON (2) Once the product of VIN x TON is constant, the switching frequency keeps constant and is independent with input voltage. VOUT VSS An external resistor between the IN and TON pin sets the switching on-time according to the following curves: VSS=3.3V VSS=0.8V PGOOD Figure 1. Soft Start Sequence of AOZ2261QI-11 Rev. 0.1 May 2016 www.aosmd.com Page 9 of 16 AOZ2261QI-11 constant-on-time control is significantly improved even without the help of output capacitor's ESR; and thus the pure ceramic capacitor solution can be applicant. The pure ceramic capacitor solution can significantly reduce the output ripple (no ESR caused overshoot and undershoot) and less board area design. On-Time vs. On-Time Resistance On-Time (nS) (@ VIN=5V~15V) 1130 1064 998 932 866 800 734 668 602 536 470 404 338 272 206 140 VIN=5V VIN=7V VIN=9V VIN=11V VIN=13V VIN=15V Current-Limit Protection 60 74 88 102 116 130 144 158 172 186 The AOZ2261QI-11 uses the current-limit protection by using RDSON of the low-side MOSFET to be as current sensing. To detect real current information, a minimum constant off (300ns typical) is implemented after a constant-on time. If the current exceeds the current-limit threshold, the PWM controller is not allowed to initiate a new cycle. The actual peak current is greater than the current-limit threshold by an amount equal to the inductor ripple current. Therefore, the exact current-limit characteristic and maximum load capability are a function of the inductor value and input and output voltages. The current limit will keep the low-side MOSFET on and will not allow another high-side on-time, until the current in the low-side MOSFET reduces below the current limit. 200 On-Time Resistance (K) On-Time vs. On-Time Resistance On-Time (nS) (@ VIN=17V~28V) 315 299 283 267 251 235 219 203 187 171 155 139 123 107 91 75 VIN=17V VIN=19V VIN=21V VIN=24V VIN=26V VIN=28V 60 74 88 102 116 130 144 158 172 186 After 64 switching cycles, the AOZ2261QI-11 considers this is a true failed condition and therefore, turns-off both high-side and low-side MOSFETs and latches off. Only when triggered, the enable can restart the AOZ2261QI11 again. 200 Figure 3. TON vs. ROn-Time for AOZ2261QI-11 TON Curves Resistance (K) Figure 3. TON vs RTON Curves for AOZ2261QI-11 Output Voltage Under-Voltage Protection A further simplified equation will be: V OUT V 6 F SW kHz = ------------------------------------------------ 10 V IN V T ON ns (3) If VOUT is 1.05V, VIN is 19V, and set FS = 500kHz. According to equation 3, TON = 110ns is needed. Finally, use the TON to RTON curve, we can find out RTON is 82k. This algorithm results in a nearly constant switching frequency despite the lack of a fixed-frequency clock generator. True Current Mode Control The constant-on-time control scheme is intrinsically unstable if output capacitor's ESR is not large enough as an effective current-sense resistor. Ceramic capacitors usually cannot be used as output capacitor. The AOZ2261QI-11 senses the low-side MOSFET current and processes it into DC current and AC current information using AOS proprietary technique. The AC current information is decoded and added on the FB pin on phase. With AC current information, the stability of Rev. 0.1 May 2016 If the output voltage is lower than 70% by over-current or short circuit, the AOZ2261QI-11 will wait for 32s (typical) and turns-off both high-side and low-side MOSFETs and latches off. Only when triggered, the enable can restart the AOZ2261QI-11 again. Output Voltage Over-Voltage Protection The threshold of OVP is set 20% higher than 0.8V. When the VFB voltage exceeds the OVP threshold, the highside MOSFET is turned-off and the low-side MOSFETs is turned-on at 1s, then latch-off. Power Good Output The power good (PGOOD) output, which is an open drain output, requires the pull-up resistor. When the output voltage is 15% below than the nominal regulation voltage, the PGOOD is pulled low. When the output voltage is 20% higher than the nominal regulation voltage, the PGOOD is also pulled low. When combined with the under-voltage-protection circuit, this current limit method is effective in almost every circumstance. www.aosmd.com Page 10 of 16 AOZ2261QI-11 Application Information The basic AOZ2261QI-11 application circuit is shown in page 2. Component selection is explained below. Input Capacitor The input capacitor must be connected to the IN pins and PGND pin of the AOZ2261QI-11 to maintain steady input voltage and filter out the pulsing input current. A small decoupling capacitor, usually 1uF, should be connected to the VCC pin and AGND pin for stable operation of the AOZ2261QI-11. The voltage rating of input capacitor must be greater than maximum input voltage plus ripple voltage. The input ripple voltage can be approximated by equation below: Inductor VO VO IO V IN = ----------------- 1 - --------- --------V IN V IN f C IN (4) Since the input current is discontinuous in a buck converter, the current stress on the input capacitor is another concern when selecting the capacitor. For a buck circuit, the RMS value of input capacitor current can be calculated by: VO VO I CIN_RMS = I O --------- 1 - --------- V IN V IN (5) if let m equal the conversion ratio: VO -------- = m V IN (6) The relation between the input capacitor RMS current and voltage conversion ratio is calculated and shown in Figure 4. It can be seen that when VO is half of VIN, CIN is under the worst current stress. The worst current stress on CIN is 0.5 x IO. The inductor is used to supply constant current to output when it is driven by a switching voltage. For given input and output voltage, inductance and switching frequency together decide the inductor ripple current, which is: VO VO I L = ----------- 1 - --------- V IN fL (7) The peak inductor current is: I L I Lpeak = I O + -------2 (8) High inductance gives low inductor ripple current but requires larger size inductor to avoid saturation. Low ripple current reduces inductor core losses. It also reduces RMS current through inductor and switches, which results in less conduction loss. Usually, peak to peak ripple current on inductor is designed to be 30% to 50% of output current. When selecting the inductor, make sure it is able to handle the peak current without saturation even at the highest operating temperature. The inductor takes the highest current in a buck circuit. The conduction loss on inductor needs to be checked for thermal and efficiency requirements. 0.5 0.4 Surface mount inductors in different shape and styles are available from Coilcraft, Elytone and Murata. Shielded inductors are small and radiate less EMI noise. But they cost more than unshielded inductors. The choice depends on EMI requirement, price and size. ICIN_RMS(m) 0.3 IO 0.2 0.1 0 For reliable operation and best performance, the input capacitors must have current rating higher than ICIN-RMS at worst operating conditions. Ceramic capacitors are preferred for input capacitors because of their low ESR and high ripple current rating. Depending on the application circuits, other low ESR tantalum capacitor or aluminum electrolytic capacitor may also be used. When selecting ceramic capacitors, X5R or X7R type dielectric ceramic capacitors are preferred for their better temperature and voltage characteristics. Note that the ripple current rating from capacitor manufactures is based on certain amount of life time. Further de-rating may be necessary for practical design requirement. 0 0.5 m 1 Figure 4. ICIN vs. Voltage Conversion Ratio Rev. 0.1 May 2016 www.aosmd.com Page 11 of 16 AOZ2261QI-11 Output Capacitor The output capacitor is selected based on the DC output voltage rating, output ripple voltage specification and ripple current rating. The selected output capacitor must have a higher rated voltage specification than the maximum desired output voltage including ripple. De-rating needs to be considered for long term reliability. Output ripple voltage specification is another important factor for selecting the output capacitor. In a buck converter circuit, output ripple voltage is determined by inductor value, switching frequency, output capacitor value and ESR. It can be calculated by the equation below: 1 V O = I L ESR CO + ------------------------- 8fC (9) O where, CO is output capacitor value and ESRCO is the Equivalent Series Resistor of output capacitor. When a low ESR ceramic capacitor is used as output capacitor, the impedance of the capacitor at the switching frequency dominates. Output ripple is mainly caused by capacitor value and inductor ripple current. The output ripple voltage calculation can be simplified to: 1 V O = I L ------------------------8fC (10) O If the impedance of ESR at switching frequency dominates, the output ripple voltage is mainly decided by capacitor ESR and inductor ripple current. The output ripple voltage calculation can be further simplified to: V O = I L ESR CO (11) For lower output ripple voltage across the entire operating temperature range, X5R or X7R dielectric type of ceramic, or other low ESR tantalum are recommended to be used as output capacitors. In a buck converter, output capacitor current is continuous. The RMS current of output capacitor is decided by the peak to peak inductor ripple current. It can be calculated by: I L I CO_RMS = ---------12 inductor ripple current is high, the output capacitor could be overstressed. Thermal Management and Layout Consideration In the AOZ2261QI-11 buck regulator circuit, high pulsing current flows through two circuit loops. The first loop starts from the input capacitors, to the VIN pin, to the LX pins, to the filter inductor, to the output capacitor and load, and then return to the input capacitor through ground. Current flows in the first loop when the high side switch is on. The second loop starts from inductor, to the output capacitors and load, to the low side switch. Current flows in the second loop when the low side low side switch is on. In PCB layout, minimizing the two loops area reduces the noise of this circuit and improves efficiency. A ground plane is strongly recommended to connect input capacitor, output capacitor, and PGND pin of the AOZ2261QI-11. In the AOZ2261QI-11 buck regulator circuit, the major power dissipating components are the AOZ2261QI-11 and the output inductor. The total power dissipation of converter circuit can be measured by input power minus output power. P total_loss = V IN I IN - V O I O (13) The power dissipation of inductor can be approximately calculated by DCR of inductor and output current. P inductor_loss = IO2 R inductor 1.1 (14) The actual junction temperature can be calculated with power dissipation in the AOZ2261QI-11 and thermal impedance from junction to ambient. T junction = P total_loss - P inductor_loss JA (15) The maximum junction temperature of AOZ2261QI-11 is 150C, which limits the maximum load current capability. The thermal performance of the AOZ2261QI-11 is strongly affected by the PCB layout. Extra care should be taken by users during design process to ensure that the IC will operate under the recommended environmental conditions. (12) Usually, the ripple current rating of the output capacitor is a smaller issue because of the low current stress. When the buck inductor is selected to be very small and Rev. 0.1 May 2016 www.aosmd.com Page 12 of 16 AOZ2261QI-11 Layout Considerations Several layout tips are listed below for the best electric and thermal performance. 1. The LX pins and pad are connected to internal low side switch drain. They are low resistance thermal conduction path and most noisy switching node. Connect a large copper plane to LX pin to help thermal dissipation. 5. Voltage divider R1 and R2 should be placed as close as possible to FB and AGND. 6. RTON should be connected as close as possible to Pin 6 (TON pin). 7. A ground plane is preferred; Pin 19 (PGND) must be connected to the ground plane through via. 2. The IN pins and pad are connected to internal high side switch drain. They are also low resistance thermal conduction path. Connect a large copper plane to IN pins to help thermal dissipation. 8. Keep sensitive signal traces such as feedback trace far away from the LX pins. 9. Pour copper plane on all unused board area and connect it to stable DC nodes, like VIN, GND or VOUT. 3. Input capacitors should be connected to the IN pin and the PGND pin as close as possible to reduce the switching spikes. 4. Decoupling capacitor CVCC should be connected to VCC and AGND as close as possible. Vout 3*1' /; PGND PGND %67 /; /; /; 9&& PGND /; ,1 /; ,1 ,1 Vin 66 3*22' PGND PGND (1 3)0 $*1' )% 721 ,1 , Vout Rev. 0.1 May 2016 www.aosmd.com Page 13 of 16 AOZ2261QI-11 Package Dimensions, QFN 4x4, 22 Lead EP2_S D D2 Pin #1 Dot By Marking L1 D3 L5 L5 L e E E3 E1 E2 b L4 L2 L3 D1 D1 TOP VIEW BOTTOM VIEW A1 A A2 SIDE VIEW RECOMMENDED LAND PATTERN 0.25 0.60 1.00 0.25 0.22 0.50 0.45 3.10 2.75 3.10 0.04 3.43 0.25 0.75 1.20 0.27 0.75 UNIT: MM 0.85 Dimensions in inches Dimensions in millimeters Symbols Min. Typ. Max. Symbols Min. Typ. Max. A A1 A2 E E1 E2 E3 D D1 D2 D3 L L1 L2 L3 L4 L5 b e 0.80 0.00 0.90 -- 0.2 REF 4.00 3.05 1.75 3.05 4.00 0.75 0.85 1.20 0.40 0.62 0.28 0.62 0.35 0.27 0.25 0.50 BSC 1.00 0.05 A A1 A2 E E1 E2 E3 D D1 D2 D3 L L1 L2 L3 L4 L5 b e 0.031 0.000 0.035 -- 0.008 REF 0.157 0.120 0.069 0.120 0.157 0.030 0.033 0.047 0.016 0.024 0.011 0.024 0.014 0.011 0.010 0.020 BSC 0.039 0.002 3.90 2.95 1.65 2.95 3.90 0.65 0.75 1.10 0.35 0.57 0.23 0.57 0.30 0.17 0.20 4.10 3.15 1.85 3.15 4.10 0.85 0.95 1.30 0.45 0.67 0.33 0.67 0.40 0.37 0.30 0.153 0.116 0.065 0.116 0.153 0.026 0.029 0.043 0.014 0.022 0.009 0.022 0.012 0.007 0.008 0.161 0.124 0.073 0.124 0.161 0.034 0.037 0.051 0.018 0.026 0.013 0.026 0.016 0.015 0.012 Notes: 1. Controlling dimensions are in millimeters. Converted inch dimensions are not necessarily exact. 2. Tolerance: 0.05 unless otherwise specified. 3. Radius on all corners is 0.152 max., unless otherwise specified. 4. Package wrapage: 0.012 max. 5. No plastic flash allowed on the top and bottom lead surface. 6. Pad planarity: 0.102 7. Crack between plastic body and lead is not allowed. Rev. 0.1 May 2016 www.aosmd.com Page 14 of 16 AOZ2261QI-11 Tape and Reel Dimensions, QFN 4x4 Carrier Tape P1 P2 D1 T E1 E2 E B0 K0 D0 P0 A0 Feeding Direction UNIT: mm Package A0 B0 K0 D0 QFN 4x4 (12mm) 4.35 0.10 4.35 0.10 1.10 0.10 1.50 Min. D1 E 1.50 +0.10/-0 12.00 0.30 Reel E1 E2 P0 P1 P2 T 1.75 0.10 5.50 0.05 8.00 0.10 4.00 0.10 2.00 0.05 0.30 0.05 W1 S G N M K V R H W UNIT: mm Tape Size Reel Size 12mm o330 M o330.0 2.0 N o79.0 1.0 W 12.4 +2.0/-0.0 W1 17.0 +2.6/-1.2 H o13.0 0.5 K 10.5 0.2 S 2.0 0.5 G -- R -- V -- Leader/Trailer and Orientation Trailer Tape 300mm min. Rev. 0.1 May 2016 Components Tape Orientation in Pocket www.aosmd.com Leader Tape 500mm min. Page 15 of 16 AOZ2261QI-11 Part Marking AOZ2261QI-11 (QFN4x4) Z2261QIB Part Number Code FAYWLT Assembly Lot Code Fab & Assembly Location Year & Week Code Part Number Part Number Code of Marking AOZ2261QI-10 AOZ2261QI-11 AOZ2261QI-12 AOZ2261QI-13 AOZ2261QI-14 AOZ2261QI-15 AOZ2261QI-16 AOZ2261QI-17 Z2261QIA Z2261QIB Z2261QIC Z2261QID Z2261QIE Z2261QIF Z2261QIG Z2261QIH 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. 0.1 May 2016 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 16 of 16