Analog Devices Inc./Maxim Integrated

The LT3492 is a triple output DC/DC converter designed to operate as a constant-current source and is ideal for driving LEDs. The LT3492 works in buck, boost or buck-boost mode. The LT3492 uses a fixed frequency, current mode architecture resulting in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 330kHz and 2.1MHz to optimize efficiency and external component size.The external PWM input provides 3000:1 LED dimming on each channel. Each of the three channels has a built-in gate driver to drive an external LED-disconnect P-channel MOSFET, allowing high dimming range. The output current range of each channel of the LT3492 is programmed with an external sense resistor.The CTRL pin is used to adjust the LED current either for analog dimming or over-temperature protection.ApplicationsRGB LightingBillboards and Large DisplaysAutomotive and Avionic LightingConstant-Current Sources

The LT3493 is a current mode PWM step-down DC/DC converter with an internal 1.75A power switch. The wide operating input range of 3.6V to 36V (40V maximum) makes the LT3493 ideal for regulating power from a wide variety of sources, including unregulated wall transformers, 24V industrial supplies and automotive batteries. Its high operating frequency allows the use of tiny, low cost inductors and ceramic capacitors, resulting in low, predictable output ripple.Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates input current surge during start-up. The low current (<2µA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems.VINRangeLT34933.6V to 36V Operating,40V MaximumLT3493-36.8V to 36V Operating,40V MaximumApplicationsAutomotive Battery RegulationIndustrial Control SuppliesWall Transformer RegulationDistributed Supply RegulationBattery-Powered Equipment

The LT3493-3 is a current mode PWM step-down DC/DC converter with an internal 1.75A power switch. The wide operating input range of 6.8V to 36V (40V maximum) makes the LT3493-3 ideal for regulating power from a wide variety of sources, including unregulated wall transformers, 24V industrial supplies and automotive batteries. Its high operating frequency allows the use of tiny, low cost inductors and ceramic capacitors, resulting in low, predictable output ripple.Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates input current surge during start-up. The low current (<2µA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems.VINRangeLT34933.6V to 36V Operating, 40V MaximumLT3493-36.8V to 36V Operating, 40V MaximumApplicationsAutomotive Battery RegulationIndustrial Control SuppliesWall Transformer RegulationDistributed Supply RegulationBattery-Powered Equipment

The LT3496 is a triple output DC/DC converter designed to operate as a constant-current source and is ideal for driving LEDs. The LT3496 works in buck, boost or buck-boost mode. The LT3496 uses a fixed frequency, current mode architecture resulting in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 330kHz and 2.1MHz to optimize efficiency and external component size.The LT3496 supports 3000:1 dimming control on each channel. Each of the three regulators is independently operated by that channel’s PWM signal. The PWM feature allows precise adjustment of the color mixing or dimming ratio of the LED source. Each of the three channels has a built-in gate driver to drive an external LED-disconnect P-channel MOSFET, allowing high dimming range. The output current range of each channel of the LT3496 is programmed with an external sense resistor.The CTRL pins are used to adjust the LED currents either for analog dimming or overtemperature protection.ApplicationsRGB LightingBillboards and Large DisplaysAutomotive and Avionic LightingConstant-Current Sources

The LT3498 is a dual output boost converter featuring a 2.3MHz PWM LED Driver and PFM OLED Driver. It includes an internal power switch and Schottky diode for each driver. Both converters can be independently shut down and modulated. This highly integrated power solution is ideal for dual display electronic devices.The 2.3MHz step-up converter is designed to drive up to six white LEDs in series from a Li-Ion cell. The device features a unique high side LED current sense that enables the part to function as a "one-wire" current source—one side of the LED string can be returned to ground anywhere. Traditional LED drivers use a grounded resistor to sense LED current, requiring a 2-wire connection to the LED string.The PFM OLED driver is a low noise boost converter that features a novel control technique.* The converter controls power delivery by varying both the peak inductor current and switch off time. This technique results in low output voltage ripple, as well as, high efficiency over a wide load range. The off time of the switch is not allowed to exceed a fixed level, guaranteeing a switching frequency that stays above the audio band.ApplicationsCellular PhonesPDAs, Handheld ComputersDigital CamerasMP3 PlayersGPS Receivers