MIC2842AYMT TR Micrel Inc, MIC2842AYMT TR Datasheet

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... LCD Display Backlight with Four WLEDs DAM and Dynamic Average Matching is a trademark of Micrel, Inc. MLF and MicroLeadFrame are registered trademark Amkor Technology Inc. Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 ( August 2009 MIC2842A High Efficiency 4 Channel WLED Driver with DAM™ ...

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... Micrel Inc. Ordering Information Part Number Mark Code MIC2842AYMT R2Y Note: ® 1. Thin MLF ▲ = Pin 1 identifier. ® 2. Thin MLF is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is halogen free. Pin Configuration Pin Description Pin Number Pin Name 1 VIN ...

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... Micrel Inc. Absolute Maximum Ratings Main Input Voltage (V ) .................................. –0.3V to +6V IN Enable Input Voltage (V ) ............................ –0.3V to +6V END LED Driver Voltage (V ) ............................ –0.3V to +6V D1-D4 Power Dissipation .....................................Internally Limited Lead Temperature (soldering, 10sec.)....................... 260°C Storage Temperature (T ) .........................–65°C to +150°C s (3) ESD Rating ...

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... Micrel Inc. Typical Characteristics August 2009 4 MIC2842A M9999-080309-D ...

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... Micrel Inc. Functional Characteristics August 2009 5 MIC2842A M9999-080309-D ...

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... Micrel Inc. Functional Diagram VIN D1...D4 DC August 2009 BG 4 DIGITAL CONTROL POR TSD Figure 1. MIC2842A Functional Block Diagram 6 VIN V-to-I 1.27V OSC GND RSE T MIC2842A M9999-080309-D ...

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... Micrel Inc. Functional Description The MIC2842A is a four channel linear WLED driver. The WLED driver is designed to maintain proper current regulation with LED current accuracy of 1.5%, and typical matching of 1.5% across the four channels. The WLEDs are driven independently from the input supply and will maintain regulation with a dropout of 40mV at 20mA ...

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... Micrel Inc. Application Information Average Brightness Level Average Duty (0 - 48) I LED Cycle (%) 0 100 48.33 4 36.67 5 29.17 6 21.67 7 16.67 8 11.67 9 9. 3.33 13 2.5 14 1. 0.83 18 0.83 19 1.25 20 1.67 21 2.08 22 2.5 23 2.92 24 3. 5.83 28 6.67 29 7.92 30 9.17 31 10.42 32 11.67 33 14. ...

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... Micrel Inc. Figure 4. LED Current with Brightness Level Change Figure 5. LED Current 60° Phase Shift Digital Dimming Interface The MIC2842A incorporates an easy to use single-wire, serial programming interface that allows users to set LED brightness different levels, as shown in the table1. Brightness levels 0 through 15 are logarithmically ...

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... Micrel Inc. Count Up Mode until its mode is changed to Count Down Mode or by disabling the MIC2842A to reset the mode back to default. Figure 8. Mode Change to Count Up To change the mode back to Count Down Mode, pull the DC pin low for a period equal to t 500µs), shown in Figure 9. Now the internal circuitry will remain in Count Down Mode until changed to Count Up as described previously ...

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... Micrel Inc. Figure 12. Down Counter Roll-Over Similarly, when the counter mode is set to Count Up and a programming pulse forces the brightness level to step up from level 48, then the counter will roll-over to level 0 as illustrated in Figure 13. Figure 13. Up Counter Roll-Over One-Step Brightness Changes The “One-Step” brightness change procedure relieves the user from keeping track of the MIC2842A’ ...

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... Micrel Inc. Typical Application C1 1µF/6.3V R1 20.5K Bill of Materials Item Part Number C1608X5R0J105K 06036D105KAT2A C1 GRM188R60J105KE19D VJ0603G225KXYAT SWTS1007 D1 – D4 99-116UNC R1 CRCW060320K5F5EA R2 CRCW06032003FKEA U1 MIC2842AYMT Notes: 1. TDK: www.tdk.com 2. AVX: www.avx.com 3. Murata: www.murata.com 4. Vishay: www.vishay.com 5. Seoul Semiconductor: www.seoulsemicon.com 6. EverLight: www.everlight.com 7. Micrel, Inc.: www.micrel.com August 2009 ...

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... Micrel Inc. PCB Layout Recommendations August 2009 Top Layer Bottom Layer 13 MIC2842A M9999-080309-D ...

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... Micrel Inc. Package Information MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com The information furnished by Micrel in this data sheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. ...