TPS61043

TPS61043：恒流 LED 驱动器

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 typical. 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 so that the brightness is controlled by an analog signal as well, as described in _Application Information_. 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 by limiting the output voltage to typically 18 V in case of a high-impedance output for example, faulty LED. The TPS61043 device provides a solution for applications where higher LED currents or more than four LEDs in series must be powered.

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Current Source With 18-V Overvoltage Protection

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Powers up to 4 LEDs in Series

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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 400 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 Typical

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Shutdown Current 0.1 µA Typical

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Available in a Small 3-mm × 3-mm QFN Package