mic3291 Micrel Semiconductor, mic3291 Datasheet
mic3291
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mic3291 Summary of contents
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... The 2.5V to 6.5V input voltage range of the MIC3291 allows direct operation from single cell Li-Ion as well cell NiCad/NiMH/Alkaline batteries. Battery life is preserved with a low 1µA shutdown current. The MIC3291 is available in a low profile Thin SOT23 6- ® pin and 2mm × 2mm MLF 8-pin packages with a junction temperature range of – ...
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... Ground (Return): Backside pad. 2 Junction Package Temperature Range −40°C to +125°C TSOT23-6 −40°C to +125°C TSOT23-6 −40°C to +125°C 2mm × 2mm MLF −40°C to +125°C 2mm × 2mm MLF TSOT23-6 (D6) (Top View) M9999-092810 (408) 944-0800 MIC3291 2,3 ® ® ...
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... TSOT23-6 .................................................. 235°C/W JA ≤ +125°C. J Min. Typ. 2.5 1.8 2.1 2 0.01 250 237 450 0.5 0 750 500 1.1 5 1260 100 420 140 1 1 140 35 1 1.2 MIC3291 OVP Max. Units 6 μ 263 1200 V 0.4 μA 10 µs 160 µs 500 µs µs µs 32 µ ...
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... Bold values indicate −40°C ≤ T OUT Condition I = 150mA 30V R 3291- 18 only (nominal voltage) 3291- 25 only (nominal voltage) , and the ambient temperature The maximum allowable power dissipation will result in excessive die MIC3291 ≤ +125°C. J Min. Typ. Max. Units 0 μ ...
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... WHITE LED CURRENT (mA) Feedback Voltage vs. Input Voltage 260 258 256 254 252 250 V = 2.8V 248 IN 246 244 242 = 0.27µF 240 2 INPUT VOLTAGE (V) Current Limit vs. Input Voltage 1 L=10µH 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 2.6 3.1 3.6 4.1 4.6 5.1 5.6 6.1 6.6 5 5.5 6 INPUT VOLTAGE (V) MIC3291 = 3. 4. 10µ 0.27µF OUT 4.5 5 5.5 6 M9999-092810 (408) 944-0800 ...
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... Micrel, Inc. Functional Characteristics September 2010 6 MIC3291 M9999-092810 (408) 944-0800 ...
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... Micrel, Inc. Functional Characteristics (Continued) September 2010 7 MIC3291 M9999-092810 (408) 944-0800 ...
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... Micrel, Inc. Functional Diagram September 2010 MIC3291 Block Diagram 8 MIC3291 M9999-092810 (408) 944-0800 ...
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... Table 1. Brightness Level vs. Ideal FB Voltage Startup Presuming no presetting brightness command is issued (discussed in a later section), the MIC3291 will startup in its default state approximately 140µs (t logic level high has been applied and maintained at the DC pin. In the default state the LED drive current is at the maximum brightness level of 15 and brightness counter is set to count down mode ...
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... MIC3291 internal circuit can be changed from count down mode to count up mode and vice versa. The user may elect to send a mode change as shown in Figure 4 to set the MIC3291 to step up the brightness level with subsequent programming pulses. For proper operation, ensure the DC pin has remained HIGH for at least ...
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... This “one step” brightness change procedure relieves the user from keeping track of the MIC3291’s up/down counter mode. It combines a counter mode change with a programming pulse, therefore a one step decrease in brightness is assured no matter what the previous up/down counter mode was ...
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... LED brightness. The first presetting pulse edge must occur somewhere between the timeframe of 35µs to 50µs after DC pin is first pulled HIGH otherwise the MIC3291 may continue to start at the full (default) brightness level. Figure 12. Preset Timing ...
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... Micrel, Inc. Typical Application Circuit (MIC3291-xxYML) Bill of Materials Item Part Number C1 GRM185R61A105KE36D C2 GRM21BR71E474KCO1L R1 CRCW060312R40FRT1 L1 VLS252010T-100M U1 MIC3291-xxYML Notes: 1. Murata: www.murata.com. 2. Vishay: www.vishay.com. 3. TDK: www.tdk.com. 4. Micrel, Inc.: www.micrel.com. September 2010 Manufacturer Description (1) Murata Capacitor, 1µF Ceramic, 10V, X5R, Size 0603 (1) Murata Capacitor, 0.47µF Ceramic, 25V, X7R, Size 0805 ...
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... Micrel, Inc. Typical Application Circuit (MIC3291-xxYD6) Bill of Materials Item Part Number C1 GRM185R61A105KE36D C2 GRM21BR71E474KCO1L R1 CRCW060312R40FRT1 L1 VLS252010T-100M U1 MIC3291-xxYD6 Notes: 1. Murata: www.murata.com. 2. Vishay: www.vishay.com. 3. TDK: www.tdk.com. 4. Micrel, Inc.: www.micrel.com. September 2010 Manufacturer Description (1) Murata Capacitor, 1µF Ceramic, 10V, X5R, Size 0603 (1) Murata Capacitor, 0.47µF Ceramic, 25V, X7R, Size 0805 ...
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... Micrel, Inc. PCB Layout Recommendations September 2010 Top Layer Bottom Layer 15 MIC3291 M9999-092810 (408) 944-0800 ...
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... Micrel, Inc. Package Information September 2010 6-Pin TSOT23 (D6) 16 MIC3291 M9999-092810 (408) 944-0800 ...
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... Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully September 2010 ® 8-Pin MLF (ML) indemnify Micrel for any damages resulting from such use or sale. © 2010 Micrel, Incorporated. 17 http://www.micrel.com M9999-092810 (408) 944-0800 MIC3291 nt ...