TPS61042

采用 QFN-8 封装的 30V 500mA 开关升压转换器，用于白光 LED 应用领域

The is a high frequency boost converter with constant current output that drives white LEDs or similar. The LED current is set with the external sense resistor RS and is directly regulated by the feedback pin FB that regulates the voltage across the sense resistor RS to 252 mV typ. To control LED brightness, the LED current can be pulsed by applying a PWM pulse width modulated signal with a frequency range of 100 Hz to 50 kHz to the control pin CTRL. To allow higher flexibility, the device can be configured where the brightness can be controlled by an analog signal as well, as described in the _application information_ section. To avoid possible leakage currents through the LEDs during shutdown, the control pin CTRL disables the device and disconnects the LEDs from ground. For maximum safety during operation, the output has integrated overvoltage protection that prevents damage to the device in case of a high impedance output e.g. faulty LED.

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Current Source With Overvoltage Protection

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Input Voltage Range: 1.8 V to 6 V

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Internal 30 V Switch

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Up to 85% Efficiency

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Precise Brightness Control Using PWM Signal or

Analog Signal

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Switching Frequency: Up to 1 MHz

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Internal Power MOSFET Switch: 500 mA

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Operates With Small Output Capacitors Down to 100 nF

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Disconnects LEDs During Shutdown

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No Load Quiescent Current: 38 µA Typ

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Shutdown Current: 0.1 µA Typ

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Available in a Small 3 mm × 3 mm QFN Package