LT3587 High Voltage Monolithic Inverter and Dual Boost FEATURESDESCRIPTION n Ideal for CCD, LCD, LED Backlight and OLED The LT®3587 provides a one chip solution for applications Applications requiring two positive and one negative high voltage sup- n Easy Generation of 15V (50mA), –8V (100mA) and plies. The LT3587 input voltage range of 2.5V to 6V makes 20V (20mA) from a Li-Ion Cell it ideal for various battery-powered systems. n VVIN Range: 2.5V to 6V A single resistor programs each of the three output voltage n Wide Output Ranges: Up to 32V for the Boosts and levels and the output current of Boost3. The intelligent soft- Up to –32V for the Inverter start allows for sequential soft-start of the Boost1 output n
Output Disconnect for the Boost Channels followed by the negative output with a single capacitor. n
Boost3 Allows Voltage Programming and/or Current Internal sequencing circuitry also disables the inverter until Programming for a ‘One Wire Current Source’ the Boost1 output has reached 87% of its fi nal value. n
Overload Fault Protection with Fault I/O Pin Indicator n
Combined Soft-Start and Enable Pins The LT3587 integrates all the power switches, soft-start, n
Small 20-Pin 3mm × 3mm QFN Package and output-disconnect circuits into a small 3mm × 3mm QFN package. This high level of integration combined APPLICATIONS with small external components makes the LT3587 ideal for space constrained applications. n Digital Still and Video Cameras L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Scanner and Display Systems n PDA, Cellular Phones and Handheld Computers n LED Backlight and OLED Display Drivers n CCD Imager Bias n General High Voltage Supply Bias TYPICAL APPLICATIONLi-Ion Powered Supply for CCD Imager and Six White Backlight LEDs VVIN 2.5V TO 6V 10μH 15μH Effi ciency Curve 1μF 90 800 2.2μF CDD+ = 50mA 10μF CDD+ SW3 V SW1 IN 85 CDD– = 100mA 700 CAP3 CAP1 CCD POSITIVE LED = 20mA POWER DISSIP 15V, 50mA I 80 600 FB3 VOUT1 8.06k 1M ALL CHANNELS GND FB1 75 500 ENABLED LT3587 2.7pF 70 400 A CDD– TION (mW) LED DRIVER EN/SS1 V 20mA, UP TO 6 LEDS 65 300 OUT3 EFFICIENCY (%) LED V POWER DISSIPATION FB3 EN/SS3 60 ALL CHANNELS 200 1M FLT ENABLED SW2 FB2 55 100 6.8pF 2.2μF 50 0 V 15μH 15μH VIN 0 0.5 1 1.5 2.5V TO 6V CCD NEGATIVE NORMALIZED CURRENT 3587 TA01b 22μF –8V, 100mA 3587 TA01a 3587fc 1
