AOZ1019 EZBuck™ 2A Simple Regulator General Description Features The AOZ1019 is a high efficiency, simple to use, 2A buck regulator. The AOZ1019 works from a 4.5V to 16V input voltage range, and provides up to 2A of continuous output current with an output voltage adjustable down to 0.8V. ● ● ● ● The AOZ1019 comes in an SO-8 package and is rated over a -40°C to +85°C ambient temperature range. ● ● ● ● ● ● ● ● 4.5V to 16V operating input voltage range 130mΩ internal PFET switch for high efficiency: up to 95% Internal soft start Output voltage adjustable to 0.8V 2A continuous output current Fixed 500kHz PWM operation Cycle-by-cycle current limit Short-circuit protection Under voltage lockout Output over voltage protection Thermal shutdown Small size SO-8 package Applications ● ● ● ● ● ● ● Point of load DC/DC conversion PCIe graphics cards Set top boxes DVD drives and HDD LCD panels Cable modems Telecom/Networking/Datacom equipment Typical Application VIN C1 22µF Ceramic VIN L1 4.7µH VOUT LX EN AOZ1019 R2 COMP C5 1nF C4, C6 22µF Ceramic FB R2 20kΩ C2 AGND PGND R3 Figure 1. 3.3V/2A Buck Regulator Rev. 1.0 September 2007 www.aosmd.com Page 1 of 14 AOZ1019 Ordering Information Part Number Ambient Temperature Range Package Environmental AOZ1019AI -40°C to +85°C SO-8 RoHS Pin Configuration NC 1 8 PGND VIN 2 7 LX AGND 3 6 EN FB 4 5 COMP SO-8 (Top View) Pin Description Pin Number Pin Name Pin Function 1 NC Not connected. 2 VIN Supply voltage input. When VIN rises above the UVLO threshold the device starts up. 3 AGND 4 FB 5 COMP 6 EN The enable pin is active high. Connect EN pin to VIN if not used. Do not leave the EN pin floating. 7 LX PWM output connection to inductor. Thermal connection for output stage. 8 PGND Reference connection for controller section. Also used as thermal connection for controller section. Electrically needs to be connected to PGND. The FB pin is used to determine the output voltage via a resistor divider between the output and GND. External loop compensation pin. Power ground. Electrically needs to be connected to AGND. Block Diagram VIN UVLO & POR EN Internal +5V 5V LDO Regulator OTP + ISen – Reference & Bias Softstart Q1 ILimit + + 0.8V EAmp FB – – PWM Comp PWM Control Logic + Level Shifter + FET Driver LX COMP + 0.2V 0.96V Frequency Foldback Comparator 500kHz/63kHz Oscillator – + Over Voltage Protection Comparator – AGND Rev. 1.0 September 2007 www.aosmd.com PGND Page 2 of 14 µ AOZ1019 Absolute Maximum Ratings Recommend Operating Ratings Exceeding the Absolute Maximum ratings may damage the device. The device is not guaranteed to operate beyond the Maximum Operating Ratings. Parameter Rating Supply Voltage (VIN) LX to AGND -0.7V to VIN+0.3V EN to AGND -0.3V to VIN+0.3V FB to AGND -0.3V to 6V COMP to AGND -0.3V to 6V PGND to AGND -0.3V to +0.3V Junction Temperature (TJ) -65°C to +150°C (1) Human Body Model Machine Model 2kV 200V Note: 1. Devices are inherently ESD sensitive, handling precautions are required. Human body model rating: 1.5kΩ in series with 100pF. Rating Supply Voltage (VIN) 4.5V to 16V Output Voltage Range 0.8V to VIN Ambient Temperature (TA) -40°C to +85°C Package Thermal Resistance SO-8 (ΘJA)(2) +150°C Storage Temperature (TS) ESD Rating: Parameter 18V 87°C/W Note: 2. The value of ΘJA is measured with the device mounted on 1-in2 FR-4 board with 2oz. Copper, in a still air environment with TA = 25°C. The value in any given application depends on the user's specific board design. Electrical Characteristics TA = 25°C, VIN = VEN = 12V, VOUT = 3.3V unless otherwise specified(3) Symbol VIN VUVLO IIN Parameter Conditions Supply Voltage Min. Typ. 4.5 Input Under-Voltage Lockout Threshold VIN Rising VIN Falling Max. Units 16 V 4.00 3.70 V Supply Current (Quiescent) IOUT = 0, VFB = 1.2V, VEN >1.2V 2 3 mA IOFF Shutdown Supply Current VEN = 0V 1 10 µA VFB Feedback Voltage 0.8 0.818 0.5 Line Regulation 0.5 IFB Feedback Voltage Input Current VEN EN Input Threshold VHYS IEN 0.782 Load Regulation % 200 Off Threshold On Threshold 0.6 2.0 EN Input Hysteresis 100 EN Input Current V % nA V mV 1 µA 600 kHz 6 % MODULATOR fO Frequency 400 DMAX Maximum Duty Cycle 100 DMIN Minimum Duty Cycle 500 % Error Amplifier Voltage Gain 500 V/V Error Amplifier Transconductance 200 µA / V PROTECTION ILIM Current Limit VPR Output Over-Voltage Protection Threshold tSS 2.5 Off Threshold On Threshold 920 820 960 860 3.6 A 1000 900 mV Over-Temperature Shutdown Limit 150 °C Soft Start Interval 2.2 ms OUTPUT STAGE High-Side Switch On-Resistance VIN = 12V VIN = 5V 97 166 130 200 mΩ Note: 3. Specification in BOLD indicate an ambient temperature range of -40°C to +85°C. These specifications are guaranteed by design. Rev. 1.0 September 2007 www.aosmd.com Page 3 of 14 AOZ1019 Typical Performance Characteristics Circuit of Figure 1. TA = 25°C, VIN = VEN = 12V, VOUT = 3.3V unless otherwise specified. Light Load (DCM) Operation Full Load (CCM) Operation Vin ripple 0.1V/div Vin ripple 0.1V/div Vo ripple 20mV/div Vo ripple 20mV/div IL 1A/div IL 1A/div LX 10V/div LX 10V/div 1µs/div 1µs/div Startup to Full Load Full Load to Turnoff Vin 10V/div Vin 10V/div Vo 1V/div Vo 1V/div lin 0.5A/div lin 0.5A/div 400µs/div 400µs/div 50% to 100% Load Transient Light Load to Turnoff Vin 5V/div Vo Ripple 50mV/div Vo 1V/div lo 1A/div 100µs/div Rev. 1.0 September 2007 lin 0.5A/div 1s/div www.aosmd.com Page 4 of 14 AOZ1019 Typical Performance Characteristics (Continued) Circuit of Figure 1. TA = 25°C, VIN = VEN = 12V, VOUT = 3.3V unless otherwise specified. Short Circuit Protection Short Circuit Recovery Vo 2V/div Vo 2V/div IL 1A/div IL 1A/div 100µs/div 1ms/div AOZ1019AI Efficiency Efficiency (VIN = 12V) vs. Load Current 100 8.0V OUTPUT Efficieny (%) 95 5.0V OUTPUT 90 3.3V OUTPUT 85 80 75 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Load Current (A) Note: 4. Thermal de-rating curves for SO-8 package part under typical input and output condition based on the evaluation board. 25°C ambient temperature and natural convection (air speed <50LFM) unless otherwise specified. Derating Curve at 5V Input Derating Curve at 12V Input 2.5 Output Current (IO) Output Current (IO) 2.5 1.8V, 3.3V, 5V OUTPUT 2.0 1.5 1.0 0.5 air speed less than 50lfm 0 25 35 45 55 65 75 85 1.5 1.0 0.5 air speed less than 50lfm 0 25 Ambient Temperature (TA) Rev. 1.0 September 2007 1.8V, 3.3V, 5V, 8V OUTPUT 2.0 35 45 55 65 75 85 Ambient Temperature (TA) www.aosmd.com Page 5 of 14 AOZ1019 Detailed Description The AOZ1019 is a current-mode step down regulator with integrated high side PMOS switch. It operates from a 4.5V to 16V input voltage range and supplies up to 2A of load current. The duty cycle can be adjusted from 6% to 100% allowing a wide range of output voltage. Features include enable control, Power-On Reset, input under voltage lockout, fixed internal soft-start and thermal shut down. The AOZ1019 uses a P-Channel MOSFET as the high side switch. It saves the bootstrap capacitor normally seen in a circuit using an NMOS switch. It allows 100% turn-on of the upper switch to achieve linear regulation mode of operation. The minimum voltage drop from VIN to VO is the load current x DC resistance of MOSFET + DC resistance of buck inductor. It can be calculated by equation below: The AOZ1019 is available in SO-8 package. V O _MAX = V IN – I O × ( R DS ( ON ) + R inductor ) Enable and Soft Start where; The AOZ1019 has an internal 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 the input voltage rises to 4.0V and voltage on EN pin is HIGH. In soft start process, the output voltage is ramped to regulation voltage in typically 2.2ms. The 2.2ms soft start time is set internally. The EN pin of the AOZ1019 is active HIGH. Connect the EN pin to VIN if enable function is not used. Pulling EN to ground will disable the AOZ1019. Do not leave it open. The voltage on EN pin must be above 2.0 V to enable the AOZ1019. When voltage on EN pin falls below 0.6V, the AOZ1019 is disabled. If an application circuit requires the AOZ1019 to be disabled, an open drain or open collector circuit should be used to interface to the EN pin. Steady-State Operation Under steady-state conditions, the converter operates in fixed frequency and Continuous-Conduction Mode (CCM). The AOZ1019 integrates an internal P-MOSFET as the high-side switch. Inductor current is sensed by amplifying the voltage drop across the drain to source of the high side power MOSFET. Output voltage is divided down by the external voltage divider at the FB pin. The difference of the FB pin voltage and reference is amplified by the internal transconductance error amplifier. The error voltage, which shows on the COMP pin, is compared against the current signal, which is sum of inductor current signal and ramp compensation signal, at PWM comparator input. If the current signal is less than the error voltage, the internal high-side switch is on. The inductor current flows from the input through the inductor to the output. When the current signal exceeds the error voltage, the high-side switch is off. The inductor current is freewheeling through the internal Schottky diode to output. Rev. 1.0 September 2007 VO_MAX is the maximum output voltage, VIN is the input voltage from 4.5V to 16V, IO is the output current from 0A to 2A, RDS(ON) is the on resistance of internal MOSFET, the value is between 97mΩ and 200mΩ depending on input voltage and junction temperature, and Rinductor is the inductor DC resistance. Switching Frequency The AOZ1019 switching frequency is fixed and set by an internal oscillator. The actual switching frequency ranges from 400kHz to 600kHz due to device variation. Output Voltage Programming Output voltage can be set by feeding back the output to the FB pin with a resistor divider network as shown in Figure 1. The resistor divider network includes R2 and R3. Typically, a design is started by picking a fixed R3 value and calculating the required R2 with equation below. R V O = 0.8 × 1 + ------2- R 3 Some standard value of R2, R3 for most commonly used output voltage values are listed in Table 1. Table 1. VO (V) R2 (kΩ) R3 (kΩ) 0.8 1.0 1.2 4.99 10 1.5 10 11.5 1.8 12.7 10.2 2.5 21.5 10 3.3 31.6 10 5.0 52.3 10 www.aosmd.com Open Page 6 of 14 AOZ1019 The combination of R2 and R3 should be large enough to avoid drawing excessive current from the output, which will cause power loss. Since the switch duty cycle can be as high as 100%, the maximum output voltage can be set as high as the input voltage minus the voltage drop on upper PMOS and inductor. Protection Features The AOZ1019 has multiple protection features to prevent system circuit damage under abnormal conditions. Over Current Protection (OCP) The sensed inductor current signal is also used for over current protection. Since the AOZ1019 employs peak current mode control, the COMP pin voltage is proportional to the peak inductor current. The COMP pin voltage is limited to be between 0.4V and 2.5V internally. The peak inductor current is automatically limited cycle by cycle. The cycle by cycle current limit threshold is set between 2.5A and 3.6A. When the load current reaches the current limit threshold, the cycle by cycle current limit circuit turns off the high side switch immediately to terminate the current duty cycle. The inductor current stop rising. The cycle by cycle current limit protection directly limits inductor peak current. The average inductor current is also limited due to the limitation on peak inductor current. When cycle by cycle current limit circuit is triggered, the output voltage drops as the duty cycle decreasing. The AOZ1019 has internal short circuit protection to protect itself from catastrophic failure under output short circuit conditions. The FB pin voltage is proportional to the output voltage. Whenever FB pin voltage is below 0.2V, the short circuit protection circuit is triggered. As a result, the converter is shut down and hiccups at a frequency equals to 1/8 of normal switching frequency. The converter will start up via a soft start once the short circuit condition disappears. In short circuit protection mode, the inductor average current is greatly reduced because of the low hiccup frequency. Output Over Voltage Protection (OVP) The AOZ1019 monitors the feedback voltage: when the feedback voltage is higher than 960mV, it immediate turns-off the PMOS to protect the output voltage overshoot at fault condition. When feedback voltage is lower than 860mV, the PMOS is allowed to turn on in the next cycle. Rev. 1.0 September 2007 Power-On Reset (POR) A power-on reset circuit monitors the input voltage. When the input voltage exceeds 4V, the converter starts operation. When input voltage falls below 3.7V, the converter will stop switching. Schottky Diode Selection The external freewheeling diode supplies the current to the inductor when the high side PMOS switch is off. To reduce the losses due to the forward voltage drop and recovery of diode, Schottky diode is recommended to use. The maximum reverse voltage rating of the chosen Schottky diode should be greater than the maximum input voltage, and the current rating should be greater than the maximum load current. Thermal Protection An internal temperature sensor monitors the junction temperature. It shuts down the internal control circuit and high side PMOS if the junction temperature exceeds 150°C. Application Information The basic AOZ1019 application circuit is shown in Figure 1. Component selection is explained below. Input Capacitor The input capacitor (C1 in Figure 1) must be connected to the VIN pin and PGND pin of the AOZ1019 to maintain steady input voltage and filter out the pulsing input current. A small decoupling capacitor (Cd in Figure 1), usually 1µF, should be connected to the VIN pin and AGND pin for stable operation of the AOZ1019. 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: IO VO VO ∆V IN = ------------------ × 1 – ---------- × ---------V IN V IN f × C IN 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 www.aosmd.com Page 7 of 14 AOZ1019 reduces RMS current through the inductor and switches, which results in less conduction loss. Usually, peak to peak ripple current on inductor is designed to be 20% to 30% of output current. if let m equal the conversion ratio: VO ---------- = m V IN The relation between the input capacitor RMS current and voltage conversion ratio is calculated and shown in Figure 2 below. 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. 0.5 The inductor takes the highest current in a buck circuit. The conduction loss on the inductor needs to be checked for thermal and efficiency requirements. Surface mount inductors in different shape and styles are available from Coilcraft, Elytone and Murata. Shielded inductors are small and radiate less EMI noise. However, they cost more than unshielded inductors. The choice depends on EMI requirement, price and size. 0.4 ICIN_RMS(m) 0.3 IO 0.2 Output Capacitor The output capacitor is selected based on the DC output voltage rating, output ripple voltage specification and ripple current rating. 0.1 0 When selecting the inductor, make sure it is able to handle the peak current without saturation, even at the highest operating temperature. 0 0.5 m 1 Figure 2. ICIN vs. Voltage Conversion Ratio 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. Inductor The inductor is used to supply constant current to output when it is driven by a switching voltage. For a given input and output voltage, inductance and switching frequency together decide the inductor ripple current, which is, 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 × ES R CO + --------------------------- 8 × f × C O where; CO is output capacitor value and ESRCO is the Equivalent Series Resistor of output capacitor. VO VO ∆I L = ----------- × 1 – ---------- V IN f ×L When 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: The peak inductor current is: ∆V O = ∆I L × ES R CO ∆I I Lpeak = I O + --------L2 High inductance gives low inductor ripple current but requires larger size inductor to avoid saturation. Low ripple current reduces inductor core losses. It also Rev. 1.0 September 2007 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 × ES R CO www.aosmd.com Page 8 of 14 AOZ1019 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 G EA f p2 = -----------------------------------------2π × C C × G VEA where; GEA is the error amplifier transconductance, which is 200 x 10-6 A/V, 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 inductor ripple current is high, output capacitor could be overstressed. Loop Compensation The AOZ1019 employs peak current mode control for easy use and fast transient response. Peak current mode control eliminates the double pole effect of the output L&C filter. It greatly simplifies the compensation loop design. With peak current mode control, the buck power stage can be simplified to be a one-pole and one-zero system in frequency domain. The pole is dominant pole and can be calculated by: 1 f p1 = -----------------------------------2π × C O × R L The zero is a ESR zero due to output capacitor and its ESR. It is can be calculated by: 1 f Z 1 = -------------------------------------------------2π × C O × ESR CO GVEA is the error amplifier voltage gain, which is 500 V/V, and CC is compensation capacitor. The zero given by the external compensation network, capacitor CC (C5 in Figure 1) and resistor RC (R1 in Figure 1), is located at: 1 f Z 2 = ------------------------------------2π × C C × R C To design the compensation circuit, a target crossover frequency fC for close loop must be selected. The system crossover frequency is where control loop has unity gain. The crossover frequency is also called the converter bandwidth. Generally a higher bandwidth means faster response to load transient. However, the bandwidth should not be too high due to system stability concern. When designing the compensation loop, converter stability under all line and load condition must be considered. Usually, it is recommended to set the bandwidth to be less than 1/10 of switching frequency. The AOZ1019 operates at a fixed switching frequency range from 400kHz to 600kHz. It is recommended to choose a crossover frequency less than 50kHz. The strategy for choosing RC and CC is to set the cross over frequency with RC and set the compensator zero with CC. Using selected crossover frequency, fC, to calculate RC: where; CO is the output filter capacitor, RL is load resistor value, and ESRCO is the equivalent series resistance of output capacitor. The compensation design is actually to shape the converter close loop transfer function to get desired gain and phase. Several different types of compensation network can be used for AOZ1019. For most cases, a series capacitor and resistor network connected to the COMP pin sets the pole-zero and is adequate for a stable high-bandwidth control loop. Rev. 1.0 September 2007 In the AOZ1019, the FB and COMP pins are the inverting input and the output of internal transconductance error amplifier. A series R and C compensation network connected to COMP provides one pole and one zero. The pole is: 2π × C O VO R C = f C × ----------× ----------------------------V G ×G FB EA CS where; fC is desired crossover frequency, VFB is 0.8V, GEA is the error amplifier transconductance, which is 200x10-6 A/V, and GCS is the current sense circuit transconductance, which is 5.64 A/V. www.aosmd.com Page 9 of 14 AOZ1019 The compensation capacitor CC and resistor RC together make a zero. This zero is put somewhere close to the dominate pole fp1 but lower than 1/5 of selected crossover frequency. CC can is selected by: 1.5 C C = -----------------------------------2π × R C × f p1 The actual AOZ1019 junction temperature can be calculated with power dissipation in the AOZ1019 and thermal impedance from junction to ambient. T junction = ( P total _loss – P inductor _loss ) × Θ JA + + T ambient The maximum junction temperature of AOZ1019 is 150°C, which limits the maximum load current capability. Please see the thermal de-rating curves for the maximum load current of the AOZ1019 under different ambient temperature. The equation above can also be simplified to: CO × RL C C = ---------------------RC An easy-to-use application software which helps to design and simulate the compensation loop can be found at www.aosmd.com. Thermal Management and Layout Consideration In the AOZ1019 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 PGND pin of the AOZ1019, to the LX pins of the AOZ1019. Current flows in the second loop when the low side diode is on. In PCB layout, minimizing the two loops area reduces the noise of this circuit and improves efficiency. A ground plane is recommended to connect input capacitor, output capacitor, and PGND pin of the AOZ1019. In the AOZ1019 buck regulator circuit, the two major power dissipating components are the AOZ1019 and 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 The power dissipation of inductor can be approximately calculated by output current and DCR of inductor. P inductor _loss = IO2 × R inductor × 1.1 The power dissipation in Schottky can be approximated as: The thermal performance of the AOZ1019 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. Several layout tips are listed below for the best electric and thermal performance. Figure 3 illustrates a single layer PCB layout example as reference. 1. Do not use thermal relief connection to the VIN and the PGND pin. Pour a maximized copper area to the PGND pin and the VIN pin to help thermal dissipation. 2. Input capacitor should be connected to the VIN pin and the PGND pin as close as possible. 3. A ground plane is preferred. If a ground plane is not used, separate PGND from AGND and connect them only at one point to avoid the PGND pin noise coupling to the AGND pin. In this case, a decoupling capacitor should be connected between VIN pin and AGND pin. 4. Make the current trace from LX pins to L to Co to the PGND as short as possible. 5. Pour copper plane on all unused board area and connect it to stable DC nodes, like VIN, GND or VOUT. 6. The two LX pins are connected to internal PFET drain. They are low resistance thermal conduction path and most noisy switching node. Connected a copper plane to LX pin to help thermal dissipation. This copper plane should not be too larger otherwise switching noise may be coupled to other part of circuit. 7. Keep sensitive signal trace such as trace connected with FB pin and COMP pin far away form the LX pins. P diode_loss = I O × ( 1 – D ) × V FWSchottky Rev. 1.0 September 2007 www.aosmd.com Page 10 of 14 AOZ1019 Figure 3. AOZ1019 PCB Layout Rev. 1.0 September 2007 www.aosmd.com Page 11 of 14 AOZ1019 Package Dimensions D Gauge Plane Seating Plane e 0.25 8 L E E1 h x 45° 1 C θ 7° (4x) A2 A 0.1 b A1 Dimensions in millimeters 2.20 5.74 1.27 0.80 Unit: mm Symbols A A1 A2 b c D E1 e E h L θ Min. 1.35 0.10 1.25 0.31 0.17 4.80 3.80 Nom. 1.65 — 1.50 — — 4.90 3.90 1.27 BSC 5.80 6.00 0.25 — 0.40 — 0° — Max. 1.75 0.25 1.65 0.51 0.25 5.00 4.00 6.20 0.50 1.27 8° Dimensions in inches Symbols A A1 A2 b c D E1 e E h L θ Min. 0.053 0.004 0.049 0.012 0.007 0.189 0.150 Nom. Max. 0.065 0.069 — 0.010 0.059 0.065 — 0.020 — 0.010 0.193 0.197 0.154 0.157 0.050 BSC 0.228 0.236 0.244 0.010 — 0.020 0.016 — 0.050 0° — 8° Notes: 1. All dimensions are in millimeters. 2. Dimensions are inclusive of plating 3. Package body sizes exclude mold flash and gate burrs. Mold flash at the non-lead sides should be less than 6 mils. 4. Dimension L is measured in gauge plane. 5. Controlling dimension is millimeter, converted inch dimensions are not necessarily exact. Rev. 1.0 September 2007 www.aosmd.com Page 12 of 14 AOZ1019 Tape and Reel Dimensions SO-8 Carrier Tape P1 D1 See Note 3 P2 T See Note 5 E1 E2 E See Note 3 B0 K0 A0 D0 P0 Feeding Direction Unit: mm Package SO-8 (12mm) A0 6.40 ±0.10 B0 5.20 ±0.10 K0 2.10 ±0.10 D0 1.60 ±0.10 D1 1.50 ±0.10 E 12.00 ±0.10 SO-8 Reel E1 1.75 ±0.10 E2 5.50 ±0.10 P0 8.00 ±0.10 P2 2.00 ±0.10 P1 4.00 ±0.10 T 0.25 ±0.10 W1 S G N M K V R H W W N Tape Size Reel Size M 12mm ø330 ø330.00 ø97.00 13.00 ±0.10 ±0.30 ±0.50 W1 17.40 ±1.00 K H 10.60 ø13.00 +0.50/-0.20 S 2.00 ±0.50 G — R — V — SO-8 Tape Leader/Trailer & Orientation Trailer Tape 300mm min. or 75 empty pockets Rev. 1.0 September 2007 Components Tape Orientation in Pocket www.aosmd.com Leader Tape 500mm min. or 125 empty pockets Page 13 of 14 AOZ1019 AOZ1019 Package Marking Z1019AI FAYWLT Part Number Assembly Lot Code Fab & Assembly Location Year & Week Code This datasheet contains preliminary data; supplementary data may be published at a later date. Alpha & Omega Semiconductor reserves the right to make changes at any time without notice. LIFE SUPPORT POLICY ALPHA & 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. 1.0 September 2007 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