sp7685 Exar Corporation, sp7685 Datasheet

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... Space Saving RoHS Compliant, Lead Free Package: 10-pin 3mm x 3mm DFN The SP7685 is a current-regulated charge pump ideal for powering high brightness LEDs for camera flash applications. The charge pump can be set to regulate two current levels for FLASH and TORCH modes. The SP7685 automatically switches modes between step-up and step-down ensuring that LED current does not depend on the forward voltage ...

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... V 0.5 μA ♦ ♦ ♦ ♦ 170 500 μs ♦ ♦ ♦ ♦ o 145 C ♦ ♦ ♦ ♦ 2.6 3.6 s SP7685, 1.2A Buck/BoostCharge Pump LED Driver typical values at 25°C. The SHDN IN, CONDITIONS V = 2.7 - 5.5V FLASH = GND Mode 100μA LOAD FLASH = High, 2x mode V = 5.5V 0.0V ...

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... Charge Pump Output Voltage external capacitor. At least 1µF is recommended. OUT Higher capacitor values reduce output ripple Date: 6/20/06 Rev T SP7685, 1.2A Buck/BoostCharge Pump LED Driver DESCRIPTION pin to ground. Choose the external current sense SET ) based on desired current in TORCH SENSE *14uA/5 (Flash Mode) ...

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... FB pin is below the regulation point for more than 32 cycles of the internal clock, the SP7685 automati- cally switches to the 2X mode. The SP7685 remains in the 2X mode until one of four things happens: 1) the enable pin EN has been toggled, 2) the Flash pin has changed from high to low thermal fault occurs ...

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... In the Torch mode, (Flash = GND) the Flash pin is set to logic low and the SP7685 FB pin regulates to 50mV output 50mV (Torch Mode) FB When in Flash mode, (Flash = V regulation voltage is set by the resistor R connected between the R SET and the equation 14μ (Flash Mode) ...

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... Measured Calculated 150 100 100 110 120 130 140 150 RSET (KΩ) Date: 6/20/06 Rev T SP7685, 1.2A Buck/BoostCharge Pump LED Driver = 25°C unless otherwise noted. A SP7685 700mA Flash output Current 900 850 800 750 700 650 600 ...

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... V OUT 1A/div Start Up 1000mA Flash V =3.6V OUT 1A/div Flash Mode TimeOut Circuit at 2.6sec. V =4.2V SP7685, 1.2A Buck/BoostCharge Pump LED Driver 7 APPLICATION INFORMATION EN V OUT OUT 1A/div =3. 1A/div =3.8V OUT V FB =1A OUT ...

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... Typical Application Circuit Ripple 1X Torch 200mA, V =4.2V IN Ripple 1X Flash 700mA, V =4.2V IN Ripple 1X Flash 1000mA, V =4.2V IN Date: 6/20/06 Rev T SP7685, 1.2A Buck/BoostCharge Pump LED Driver APPLICATION INFORMATION = 25°C unless otherwise noted. A Input Ripple Output Ripple Ripple 2X Torch 200mA, V Input Ripple Output Ripple ...

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... All the capacitors should be sur- face mount ceramic for low lead inductance necessary at the 2.4MHz switching frequency of the SP7685 and to obtain low ESR, which improves bypassing on the input and output and improves output voltage drive by reduc- ing output resistance. Ceramic capacitors with X5R or X7R temperature grade are recommended for most applications ...

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... RSENSE 0.56Ω RSENSE 0.68Ω Table 2: Resistor values and sizes Date: 6/20/06 Rev T SP7685, 1.2A Buck/BoostCharge Pump LED Driver COMPONENT SELECTION mended to be size 0603 for most applica- tions. The range of typical resistor values and sizes are shown here in Table 2. Tolerance Size Manufacturers ...

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... BSC 0.119 BSC 2.20 - 2.70 0.087 3.00 BSC 0.119 BSC 1.40 - 1.75 0.056 0.50 BSC 0.020 BSC 0.30 0.40 0.50 0.012 JL Aug09-05 / RevA SP7685, 1.2A Buck/BoostCharge Pump LED Driver 11 PACKAGE: 10 PIN DFN ø A1 SIDE VIEW E2 NOM MAX 0.036 0.039 0.001 0.002 - - - 14º 0.010 0.012 - 0.106 - 0.069 0.016 0.020 ...

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... Part Number SP7685ER-L ............................................... -40°C to +85°C ....................................... (Lead Free) 10 Pin DFN SP7685ER-L/TR ........................................ -40°C to +85°C ....................................... (Lead Free) 10 Pin DFN /TR = Tape and Reel Pack quantity is 3,000 for DFN. Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein ...