peculiarity
High voltage DC/DC boost converter with integrated FET with four switching frequency options: 156/312/625/1250 kHz
2.7V - 22V input voltage range supports 1X... 5x cell lithium-ion battery
Programmable PWM resolution from 8 to 13 bits
I 2 C and PWM brightness control
The current of the PWM output frequency and resistor passes through the LED
4 LED outputs for LED fault (short/open) detection
Low input voltage, over-temperature, over-current detection and shutdown
Minimal number of external components
Miniature SMD - 25 package, 2.466 x 2.466 x 0.6 mm
illustrate
The LP8551 is a driver for a white LED integrated boost converter. It has 4 adjustable current absorbers that can be controlled via PWM input or a serial interface compatible with i 2C.
Adaptive output voltage control of the boost converter LED drive voltage. This feature minimizes power consumption by adjusting the voltage at the lowest sufficient level under various conditions.
There is an 8-bit LED output current resolution and up to 13-bit PWM resolution for smooth and precise brightness control. A proprietary phase-shifting PWM control LED output is used to reduce the peak current to a boost converter, resulting in a smaller boost capacitance. Phase shift plans also eliminate noise.
The internal EEPROM is used to store configuration data. This allows it to probably have a minimal number of external components, making the solution very small.
The LP8551 has a safety feature that allows it to detect open-circuit or short-circuit fault LED outputs. Overcurrent conditions as well as low input voltage and improved monitoring and chip are turned on in the event of these events. By reducing the brightness of the backlight, the thermal derating function prevents the device from overheating when the set temperature has been reached.
The LP8551 is a national micro SMD-25 package.
Note: This file is not a complete data sheet. For more details about this product or to order samples, please contact your local national semiconductor sales office or visit //www.national.com/support/dir.html.
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