SC4505EVB SEMTECH [Semtech Corporation], SC4505EVB Datasheet
SC4505EVB
Related parts for SC4505EVB
SC4505EVB Summary of contents
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POWER MANAGEMENT Description The SC4505 is a high-frequency PWM current-mode step- up switching regulator with an integrated 2A power tran- sistor. Its high switching frequency (1MHz) allows the use of tiny surface-mount external passive components. The internal switch is rated ...
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POWER MANAGEMENT Absolute Maximum Rating Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied. Exposure to Absolute Maximum rated conditions ...
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POWER MANAGEMENT Electrical Characteristics (Cont.) Unless specified 3.6V, -40°C < < 85° ...
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POWER MANAGEMENT Pin Configurations TOP VIEW (16 Pin - MLPQ) Block Diagram Thermal UVLO Shutdown Reference& Internal Regulator EN_BL BL Setpoint IO1SET RO1SET AGND 2006 Semtech Corp. Ordering Information ...
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POWER MANAGEMENT Pin Descriptions Block Diagram ...
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POWER MANAGEMENT Overview The SC4505 contains a 1MHz fixed-frequency, current- mode boost converter, and two independent LED current regulators. The LED current setpoints are chosen using external resistors, and the PWM controller operates independently to keep the two currents in ...
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POWER MANAGEMENT Applications Information Boost Converter Setup The SC4505 is a fixed-frequency, current mode step-up DC-DC converter that is ideal for driving LEDs in the applications in which both backlighting and flashlighting are needed. Unlike the ballasting resistor scheme, multiple ...
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POWER MANAGEMENT Applications Information 2.7V I 0.8A 1 µ 1.5 µ H When using tiny inductors for size-sensitive applications, only a few limited selections are available that fulfill this need, and all are within the low H range ...
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POWER MANAGEMENT Applications Information VENDOR PHONE KEMET 408-986-0424 Murata 814-237-1431 Taiyo Yuden 408-573-4150 Table 5. Recommended Ceramic Capacitor Manufacturers Output Rectifying Diode Selection Schottky diodes are the ideal choice for SC4505 due to their low forward voltage drop and fast ...
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POWER MANAGEMENT Applications Information An additional advantage of PWM dimming comes to customers who prefer to avoid inrush currents when filling the boost output capacitor – simply PWM the device at 10% duty for a millisecond or two, reducing inrush ...
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POWER MANAGEMENT Applications Information VIN L1 D1 SC4505 COMP V OVP Figure 5. OVP Tweaking As shown in Figure 5, R and R are the internal resistor 1 2 divider. R and R are ...
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POWER MANAGEMENT Applications Information Layout Guideline The SC4505 contains a boost converter. The placements of the power components outside the SC4505 should follow the guideline of general boost converter layout. The application circuit (Figure 7a) will be used as an ...
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POWER MANAGEMENT Applications Information To minimize switching noise for boost converter, the output capacitor, C3, should be placed right at the bottom as displayed in Figure 6b so that loop formed by C3, D5 and the SC4505 internal switch is ...
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POWER MANAGEMENT Typical Application Circuits P1 Vin=2.6~4.6V C2 2.2u P2 0.33uF C4 R1 100 R3 6.98k R6 R5 10k 10k Figure 7a Backlight and Flashlight LED driver for Figure 7b Efficiency Curve for ...
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POWER MANAGEMENT Outline Drawing - MLPQ - 16 PIN 1 INDICATOR (LASER MARK) aaa C NOTES: Land Pattern - MLPQ - 16 (C) NOTES: Contact Information 2006 Semtech Corp DIM ...