aoz1081 Alpha & Omega Semiconductor, aoz1081 Datasheet
aoz1081
Related parts for aoz1081
aoz1081 Summary of contents
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... General Description The AOZ1081 is a high efficiency, simple to use, 1.8A buck regulator for White LED. The AOZ1081 works from a 4.5V to 16V input voltage range, and provides up to 1.8A of continuous output current with an output voltage adjustable down to 0.25V. The AOZ1081 comes in an SO-8 package and is rated over a -40° ...
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... All AOS products are offered in packages with Pb-free plating and compliant to RoHS standards. Please visit www.aosmd.com/web/quality/rohs_compliant.jsp Rev. 1.1 April 2009 4.7µH VOUT C3 22µ Figure 2. Package SO-8 for additional information. www.aosmd.com AOZ1081 Environmental RoHS Page ...
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... PWM output connection to inductor. Thermal connection for output stage. Rev. 1.1 April 2009 PGND VIN AGND COMP 4 5 SO-8 (Top View) Pin Function rises above the UVLO threshold the device starts up not used. Do not leave the EN pin floating. IN www.aosmd.com AOZ1081 Page ...
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... Note: -0.3V to +0.3V Θ 2. The value of +150°C FR-4 board with 2oz. Copper still air environment with T 25°C. The value in any given application depends on the user's spe- -65°C to +150°C cific board design. 2kV www.aosmd.com AOZ1081 VIN + ISen – Q1 Level Shifter + LX FET ...
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... Conditions Min. 4.5 V Rising IN V Falling 0.1V, V OUT COMP EN >1. 0.2375 Off Threshold On Threshold 2.0 850 100 2.5 Off Threshold On Threshold V = 12V www.aosmd.com AOZ1081 Typ. Max. Units 16 V 4 µA 0.25 0.2625 V 0.5 % 0.5 % 200 nA 0.6 V 100 mV 1000 1150 kHz % 12 % 500 ...
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... V = 3.3V unless otherwise specified. OUT IN 0.7 0.6 0.5 0.4 0.3 0.2 0 100 0.2 www.aosmd.com AOZ1081 Digital Dimming vs. LED Current 200Hz PWM Signal on EN Pin PWM Duty Cycle (%) Efficiency (V ) vs. Load Current 7.2V OUT V = 3.6V OUT 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 Load Current (A) ...
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... OUT 2V/Div I OUT 0.5A/Div V EN 2.5V/Div V OUT 2V/Div I OUT 1A/Div Rev. 1.1 April 2009 (Continued) PWM Dimming at 200Hz (90% Duty Cycle 5V/Div V OUT 2V/Div I OUT 0.5A/Div PWM Dimming at 200Hz (90% Duty Cycle 5V/Div V OUT 2V/Div I OUT 0.5A/Div Start Up www.aosmd.com AOZ1081 Page ...
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... EN pin is HIGH. In soft start process, the output volt- age is ramped to regulation voltage in typically 400µs. The 400µs soft start time is set internally. The EN pin of the AOZ1081 is active HIGH. Connect the EN pin enable function is not used. Pull ground will disable the AOZ1081 ...
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... A small decoupling capacitor (Cd in Figure 1), usually 1µF, should be connected to the V AGND pin for stable operation of the AOZ1081. The voltage rating of input capacitor must be greater than maximum input voltage plus ripple voltage. ...
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... CO_RMS 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 inductor ripple current is high, output capacitor could be overstressed. www.aosmd.com AOZ1081 1 ⎞ ------------------------- + ⎠ × × ...
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... COMP pin sets the pole-zero and is adequate for a stable high-bandwidth control loop. In the AOZ1081, FB pin and COMP pin are the inverting input and the output of internal transconductance error amplifier. A series R and C compensation network con- nected to COMP provides one pole and one zero ...
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... The second loop starts from inductor, to the output capacitors and load, to the PGND pin of the AOZ1081, to the LX pins of the AZO1081. 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 ...
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... GND Vin GND Rev. 1.1 April 2009 Vf b Figure 3. AOZ1081 PCB Layout www.aosmd.com AOZ1081 Vo ut Page ...
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... E1 e 1.27 BSC e E 5.80 6.00 6. 0.25 — 0. 0.40 — 1.27 L θ θ 0° — 8° www.aosmd.com AOZ1081 Seating Plane 0. θ Min. Nom. Max. 0.053 0.065 0.069 0.004 — 0.010 0.049 0.059 0.065 0.012 — 0.020 0.007 — 0.010 0.189 0.193 0.197 0.150 0.154 ...
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... P0 1.50 12.00 1.75 5.50 8.00 ±0.10 ±0.10 ±0.10 ±0.10 ±0. 13.00 17.40 ø13.00 10.60 ±0.30 ±1.00 +0.50/-0.20 Components Tape Orientation in Pocket www.aosmd.com AOZ1081 See Note 3 Feeding Direction 4.00 2.00 0.25 ±0.10 ±0.10 ±0. 2.00 — — — ±0.50 Leader Tape 500mm min. or 125 empty pockets ...
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... WLT Assembly Lot Code Year & Week Code 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 affect its safety or effectiveness. www.aosmd.com AOZ1081 Page ...