ZSLS7025ZI1R ZMDI, ZSLS7025ZI1R Datasheet

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Data Sheet Rev. 1.00 / June 2012 ZSLS7025 Boost LED Driver ...

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... Available Support  Demonstration Kit Physical Characteristics under no-load  Junction temperature: -40°C to 125°C protection is  RoHS compliant and For additional information on our LED driver family, visit www.zmdi.com/products/led-drivers/ ZSLS7025 Typical Application Circuit ZSLS7025 VDD GATE Q 1 TOFF CS ADJ FB ...

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... Milpitas, CA 95035-7453 01109 Dresden USA Germany Phone +49 (0)351.8822.7.533 Phone +855-ASK-ZMDI Fax +49 (0)351.8822.8.7533 (+855.275.9634) DISCLAIMER: This information applies to a product under development. Its characteristics and specifications are subject to change without notice. Zentrum Mikroelektronik Dresden AG (ZMD AG) assumes no obligation regarding future manufacture unless otherwise agreed to in writing. The information furnished hereby is believed to be true and accurate. However, under no circumstances shall ZMD AG be liable to any customer, licensee, or any other third party for any special, indirect, incidental, or consequential damages of any kind or nature whatsoever arising out any way related to the furnishing, performance, or use of this technical data ...

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ZSLS7025 Boost LED Driver Contents 1 IC Characteristics .......................................................................................................................................................... 6 1.1 Absolute Maximum/Minimum Ratings .................................................................................................................... 6 1.2 Operating Conditions ............................................................................................................................................. 6 1.3 Electrical Parameters ............................................................................................................................................. 7 1.4 Typical Performance Characteristics Graphs ......................................................................................................... 8 2 Circuit Description ....................................................................................................................................................... 10 2.1 ZSLS7025 ...

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ZSLS7025 Boost LED Driver 4.4.6 L for Setting the Frequency ......................................................................................................................... 23 1 4.4.7 R and R for Setting OVP ............................................................................................................................ 4.4.8 Q External MOSFET and ESD Protection ............................................................................................................................................................ 25 6 Pin Configuration and ...

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ZSLS7025 Boost LED Driver 1 IC Characteristics Stresses beyond those listed under “Absolute Maximum/Minimum Ratings” (section 1.1) may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other ...

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ZSLS7025 Boost LED Driver 1.3 Electrical Parameters Except as noted, test conditions for the following specifications are 25°C (typical). OP Production testing of the chip is performed at 25°C unless otherwise stated. Functional operation of the chip ...

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ZSLS7025 Boost LED Driver 1.4 Typical Performance Characteristics Graphs Figure 1.1 V vs. I with V IN OUT OUT Figure 1.3 V vs. I with V OUT OUT IN Figure 1.5 V vs. I with V IN OUT OUT © ...

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ZSLS7025 Boost LED Driver Figure 1.7 V vs. I with V OUT OUT IN _ © 2012 Zentrum Mikroelektronik Dresden AG — Rev.1.00 Data Sheet All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, ...

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ZSLS7025 Boost LED Driver 2 Circuit Description 2.1 ZSLS7025 Overview The ZSLS7025 is a constant current boost converter. Its output current is adjustable via an external current sense resistor, and it can deliver stable constant output current from a few ...

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ZSLS7025 Boost LED Driver When the input voltage on the FB pin does not exceed the internal feedback reference voltage V during start-up, Q will remain off for the configured minimum t 1 switched on again. 2.3 Internal 5V Regulator ...

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ZSLS7025 Boost LED Driver 2.6.1 Dimming Control Using an External DC Control Signal The LED output current can be set below the nominal average value defined by equation (2) using an external DC voltage control signal superimposed on the FB ...

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ZSLS7025 Boost LED Driver 2.6.2 Dimming Control Using an RC Filter to Convert a PWM Signal Voltage As shown in Figure 2.3, a filtered PWM signal can be used as an adjustable DC voltage for LED dimming ...

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ZSLS7025 Boost LED Driver 2.6.3 PWM Dimming with a Dimming Control MOSFET (Q Figure 2.4 shows the configuration for using an external PWM signal with a dimming control MOSFET Q the PWM input is high (V >2.4V When ...

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ZSLS7025 Boost LED Driver In general, setting the peak inductor current to 1.5 times the average input current is sufficient to maintain good regulation of the output current.   PEAK IN _ ...

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ZSLS7025 Boost LED Driver The switching frequency f in Hertz can be calculated from t 1  f    OFF The ripple current in the inductor can be calculated with equation (9).    ...

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ZSLS7025 Boost LED Driver 3 Operating Conditions 3.1 Under-Voltage Lockout The under-voltage lockout (UVLO) function monitors the voltage on the ZSLS7025’s VDD pin. If this voltage is lower than the UVLO threshold minus the UVLO hysteresis (V If the voltage ...

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ZSLS7025 Boost LED Driver 4 Application Circuit Design 4.1 Applications The ZSLS7025 is ideal for driving white HB-LEDs in diverse industrial, after-market automotive, and consumer lighting applications using low supply voltages, such as SELV applications optimal for driving ...

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ZSLS7025 Boost LED Driver 4.2.3 High Frequency Noise Filter Capacitor C External capacitor C forms a high-frequency noise filter for the VDD pin. For all configurations, use C VDD bypass the VDD pin using a low ESR capacitor (a 10µF ...

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... If the layout is not well-designed, the regulator could show instability as well as EMI problems. For additional guidelines, refer to the ZMDI application note PCB Layout Design Guidelines for LED Driver Circuits available at www.zmdi.com/products/led-drivers/. ...

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ZSLS7025 Boost LED Driver Application Design Example – RC Filter PWM Dimming Circuit Figure 4 VDD C VDD 4.4.1 Selecting and C VDD IN Assume I = 2.5mA. IN  V ...

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ZSLS7025 Boost LED Driver 4.4.4 Selecting and and R can be obtained       3 PWM V ...

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ZSLS7025 Boost LED Driver 4.4.5 R for Setting Input Peak Current CS Assume that   PEAK IN _ AVG     ...

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ZSLS7025 Boost LED Driver The recommended switching frequency, 20KHz < f < 200KHz, according to the switching frequency, is inversely proportional to the inductor value; for example, select L Therefore 22    kHz 100 ...

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ZSLS7025 Boost LED Driver 5 ESD Protection All pins have an ESD protection of  ±3500V according to the Human Body Model (HBM). The ESD test follows the Human Body Model based on MIL 883-H, Method 3015.8. 6 Pin Configuration ...

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ZSLS7025 Boost LED Driver Figure 6.2 SOP-8 Package Dimensions and Pin Assignments (mm, except θ) SOP-8 Package Dimensions A 1.550 ± 0.200 E A1 0.175 ± 0.075 E1 A2 1.450 Typical e b 0.420 ± 0.090 L θ c 0.214 ...

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... Milpitas, CA 95035-7453 01109 Dresden USA Germany Phone +49 (0)351.8822.7.533 Phone +855-ASK-ZMDI Fax +49 (0)351.8822.8.7533 (+855.275.9634) DISCLAIMER: This information applies to a product under development. Its characteristics and specifications are subject to change without notice. Zentrum Mikroelektronik Dresden AG (ZMD AG) assumes no obligation regarding future manufacture unless otherwise agreed to in writing. The information furnished hereby is believed to be true and accurate. However, under no circumstances shall ZMD AG be liable to any customer, licensee, or any other third party for any special, indirect, incidental, or consequential damages of any kind or nature whatsoever arising out any way related to the furnishing, performance, or use of this technical data ...