LT3486EFE#PBF

LT3486 is a dual step-up DC/DC converter specifically designed to drive up to 16 white LEDs (8 in series per converter) at constant current from a single Li-Ion cell. Series connection of LEDs provides identical LED currents resulting in uniform brightness. The two independent converters are capable of driving asymmetric LED strings. The dimming of two LED strings can be controlled independently via the respective CTRL pins. An internal dimming system allows dimming range to be extended up to 1000:1 by feeding a PWM signal to respective PWM pins. Operating frequency can be set with an external resistor over a 200KHz to 2.5MHz range. A low 200mV feedback voltage (±3% accuracy) minimizes power loss in the current setting resistor for better efficiency. Additional features include output voltage limiting when LEDs are disconnected and overtemperature protection. Applications include notebook PC display, LED camera light for cell phones, car dashboard lighting and avionics displays.

• Wide (1000:1) PWM dimming range with no colorshift
• Independent dimming and shutdown control of the LED drivers
• Drives up to 16 white LEDs at 25mA (8 per driver) from a single Li-Ion cell
• Drives up to 16 white LEDs at 100mA (8 per driver) from 12V supply
• ±3% LED current programming accuracy
• Open LED protection, 36V clamp voltage
• Fixed frequency operation up to 2.5MHz
• Wide input voltage range from 2.5V to 24V, low shutdown current ICC of <lt/> 1µA
• Overtemperature protection, maximum duty cycle of 98% at RT = 309Kohm
• 16-lead plastic TSSOP package, -40°C to 85°C temperature range

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party