al8805 Diodes, Inc., al8805 Datasheet
al8805
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al8805 Summary of contents
Page 1
... The AL8805 switches at frequency up to 1MHz. This allows the use of small size external components, hence minimizing the PCB area needed. Maximum output current of AL8805 is set via an external resistor connected between the V IN Dimming is achieved by applying either a DC voltage or a PWM signal at the CTRL input pin ...
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... AL8805 Document number: DS35030 Rev HIGH EFFICIENCY 30V 1A BUCK LED DRIVER Parameter Parameter Descriptions = V = 2.5V giving nominal average output current I CTRL REF < 2.5V) to adjust output current from 20% to CTRL OUTnom www.diodes.com AL8805 Ratings Unit 2.5 kV 200 V -0.3~36 V -0.3~ 1.25 A 150 ° ...
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... Test condition for SOT25: Device mounted on FR-4 PCB (25mm x 25mm 1oz copper, minimum recommended pad layout on top layer and thermal vias to bottom layer ground plane. For better thermal performance, larger copper pad for heat-sink is needed. ‡ AL8805 does not have a low power standby mode but current consumption is reduced when output switch is inhibited 0V. Parameter is tested with V ...
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... R = 300mΩ SET -40 -60 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5 CTRL 2.52 2. Open CTRL 2. SET 25°C A 2. www.diodes.com AL8805 V = 12V IN 1 LED R = 150mΩ SET T = 25° CTRL CTRL 12V SET 25° (V) CTRL Figure ...
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... I LED 50% 10 40% 8 30 CTRL 10 150 200 Figure 12. Duty cycle vs Input voltage www.diodes.com AL8805 V = Open CTRL SET 25° ( input voltage DS(ON) V SENSE 150mΩ SET L = 68µH ...
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... L = 68µ 150mΩ 25°C 0 Figure 16. 670mA LED current vs Input voltage 8 LEDs www.diodes.com AL8805 4 LEDs 6 LEDs 5 LEDs 7 LEDs 8 LEDs Input voltage (V) 5 LEDs 6 LEDs 7 LEDs 8 LEDs Input voltage (V) September 2010 © ...
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... LED R = 150mΩ S 200 T = 25°C A 100 3 LEDs 2 LEDs Figure 23: Switching frequency vs Input voltage www.diodes.com AL8805 = 25°C unless otherwise stated LEDs 6 LEDs 8 LEDs 5 LEDs 4 LEDs Input voltage (V) 7 LEDs 6 LEDs 8 LEDs 5 LEDs 12 15 ...
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... A 7 LEDs 8 LEDs 400 300 200 1 LED 100 3 LEDs 4 LEDs 2 LEDs Figure 29: Switching frequency vs Input voltage www.diodes.com AL8805 8 LEDs 5 LEDs 6 LEDs 7 LEDs 4 LEDs Input voltage (V) 8 LEDs 6 LEDs 7 LEDs 4 LEDs 5 LEDs ...
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... Applications Information AL8805 Operation In normal operation, when voltage is applied at +V AL8805 internal switch is turned on. Current starts to flow through sense resistor R , inductor L1, and the LEDs. The 1 current ramps up linearly, and the ramp rate is determined by the input voltage +Vin and the inductor L1. ...
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... Figure 31. Low duty cycle PWM Dimming at 500Hz AL8805 Document number: DS35030 Rev HIGH EFFICIENCY 30V 1A BUCK LED DRIVER 30% 40% 50% 60% PWM dimming [%] Figure 30. PWM Dimming at 500Hz PWM dimming [%] www.diodes.com AL8805 70% 80% 90% 100 10% September 2010 © Diodes Incorporated ...
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... Document number: DS35030 Rev HIGH EFFICIENCY 30V 1A BUCK LED DRIVER Soft Start The AL8805 does not have in-built soft-start action – this provides very fast turn off of the output the stage improving PWM dimming accuracy; nonetheless, adding an external capacitor from the CTRL pin to ground will provide a soft- start delay ...
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... P D(MAX) four-layer PCB Figure 34, shows the power derating of the AL8805 on two (one single-layer and four-layer) different 25x25mm PCB with 1oz copper standing in still air. The power Figure 34. Derating Curve for different PCB Figure 35 gives details about the PCB layout suggestions: 1 ...
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... MR16 solution also taking into account the size constraint of the lamp. AL8805 Document number: DS35030 Rev HIGH EFFICIENCY 30V 1A BUCK LED DRIVER The AL8805 guarantee high level of performance both with 12V and 12V AC DC The efficiency is generally higher than 81% and current regulation is better than 0 ...
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... SMD tantalum Kemet D case, T491X157K020AT - Not fitted X7R 0805 Generic Kemet C0805C104K5RAC (50v) NIC NMC0805X7R104K50TRPF (50v) X7R 1206 Generic Kemet C1206105K5RAC7800 (50v) NIC NMC1206X7R105K50F (50v) LPS6235 - 333MLB www.diodes.com AL8805 SUGGESTED SOURCES Diodes Zetex Diodes Zetex Diodes Zetex Kemet Kemet Kemet NIC Components ...
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... Quantity W5 SOT25 3000/Tape & Reel Identification code Y : Year 0 Week : A~Z : 1~26 week; a~z : 27~52 week; z represents 52 and 53 week X : A~Z : Internal code 3 Package Identification Code SOT25 (All Dimensions in mm www.diodes.com AL8805 7” Tape and Reel Part Number Suffix -7 A6 September 2010 © Diodes Incorporated ...
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... Customers must fully indemnify Diodes Incorporated and its representatives against any damages arising out of the use of Diodes Incorporated products in such safety-critical, life support devices or systems. Copyright © 2010, Diodes Incorporated www.diodes.com AL8805 Document number: DS35030 Rev HIGH EFFICIENCY 30V 1A BUCK LED DRIVER IMPORTANT NOTICE LIFE SUPPORT www.diodes.com AL8805 September 2010 © Diodes Incorporated ...