Features

• Low Quiescent Current
    65µA in Active Mode
    1µA in Shutdown Mode
• Switching Frequency is Non-Audible Over Entire Load Range
• Integrated Power NPN:
    350mA Current Limit (LT3494A)
    180mA Current Limit (LT3494)
• Integrated Schottky Diode
• Integrated Output Disconnect
• Integrated Output Dimming
• Wide Input Range: 2.3V to 16V
• Wide Output Range: Up to 40V
• Tiny 8-Lead 3mm x 2mm DFN Package

Typical Application

Description

The LT3494/LT3494A are low noise boost converters with integrated power switch, Schottky diode and output disconnect circuitry. The parts use a novel* control technique resulting in low output voltage ripple as well as high efficiency over a wide load current range. This technique guarantees that the switching frequency stays above the audio band for the entire load range. The parts feature a high performance NPN power switch with a 350mA and 180mA current limit for the LT3494A and LT3494 respectively. The quiescent current is a low 65µA, which is further reduced to less than 1µA in shutdown. The internal disconnect circuitry allows the output voltage to be isolated from the input during shutdown. An auxiliary reference input (CTRL pin) overrides the internal 1.225V feedback reference with any lower value allowing full control of the output voltage during operation. The LT3494/LT3494A are available in a tiny 8-lead 3mm x 2mm DFN package.