AL8807AW5-7 Diodes Inc., AL8807AW5-7 Datasheet
AL8807AW5-7
Specifications of AL8807AW5-7
Related parts for AL8807AW5-7
AL8807AW5-7 Summary of contents
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Description The AL8807 is a step-down DC/DC converter designed to drive LEDs with a constant current. The device can drive LEDs, depending on the forward voltage of the LEDs, in series from a voltage source of 6V ...
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Pin Descriptions Pin Number Pin Name Descriptions SOT25 MSOP-8EP Switch Pin. Connect inductor/freewheeling diode here, minimizing track length at this pin reduce EMI. GND GND Pin Dimming and On/Off Control Input. • ...
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Electrical Characteristics o V =12V, T =25 C, unless otherwise specified Symbol Parameter V Internal regulator start up threshold V INSU Internal regulator hysteresis V INSH threshold I Quiescent current Q I Input supply Current S V Set ...
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Typical Performance Characteristics 400 350 300 250 200 150 100 (V) IN Figure 1. Supply Current (not switching) vs. Input Voltage 100 ...
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Typical Pe erformance e Characte 68H 150m 25C 12V CTRL = PWM 500Hz PWM 1 LED ...
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Typical Performance Characteristics - INPUT VOLTAGE (V) Figure 13. LED Current Deviation vs. Input Voltage ...
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Typical Performance Characteristics - INPUT VOLTAGE (V) Figure 19. LED Current Deviation vs. Input Voltage ...
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Typical Performance Characteristics - INPUT VOLTAGE (V) Figure 25. LED Current Deviation vs. Input Voltage ...
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Applicatio on Informat tion The AL8807 hysteretic c (also known packages tha t provide a P PCB area-pow currents/smalle er PCBs that the MSOP-8E temperature ra ange. AL8807 Ope eration In normal ope ration, when v voltage ...
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Applications Information (cont.) PWM Dimming LED current can be adjusted digitally, by applying a low frequency Pulse Width Modulated (PWM) logic signal to the CTRL pin to turn the device on and off. This will produce an average output current ...
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Applications Information (cont.) Soft Start The AL8807 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 ...
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Applicatio ons Informa ation (cont. Diode Selec tion For maximum efficiency and performance, leakage at the e maximum ope erating voltage PN diodes combina ation of lower important to select parts with a ...
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Applications Information (cont.) The following equations can be used as a guide, with reference to Figure 1 - Operating waveforms. Switch ‘On’ time Δ − − ...
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Applicatio ons Informa ation (cont. EMI and Lay yout Conside erations The AL8807 switching re egulator with fa taken with dec coupling and la ayout of the PC emissions by c controlling the switching spee right comprom ...
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Applications Information (cont.) Recommendations for minimising radiated EMI and other transients and thermal considerations are: 1. The decoupling capacitor (C1) has to be placed as close as possible to the V 2. The freewheeling diode’s (D1) anode, the SW pin ...
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Applications Information (cont.) The associated EMI measurements for this board using the AL8807 is shown in figure 40. Fig 40. AL8807EV2 Radiated EMI Performance The EMI performance was measured at 12V line is for EN55022 class B used for domestic ...
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Applications Information (cont.) An inductor choice of 33µH with saturation current higher than 1.1A, will limit the frequency variation between 180kHz and 400kHz over the whole input voltage variation (8V to 18V), and therefore represent the best choice for an ...
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... MP : MSOP-8EP Device Status Package Code AL8807W5-7 New Product AL8807MP-13 New Product Notes: 8. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at: http://www.diodes.com/datasheets/ap02001.pdf . Marking Information (1) SOT25 (Top View Part Number AL8807W5-7 (2) MSOP-8EP ...
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Package Outline Dimensions (1) Package Type: SOT25 (2) MSOP-8EP 8Xb AL8807 Document number: DS35281 Rev ...
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Suggested Pad Layout 1) Package Type: SOT25 MSOP-8EP AL8807 Document number: DS35281 Rev HIGH EFFICIENCY LOW EMI 36V 1A BUCK LED DRIVER C2 C2 Dimensions Value (in ...
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DIODES INCORPORATED MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARDS TO THIS DOCUMENT, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS OF ANY ...