AL8860

Description

The AL8860 is a hysteresis mode DC-DC step-down converter, designed for driving single or multiple series connected LEDs efficiently from a voltage source higher than the LED voltage. The device can operate from an input supply between 4.5V and 40V and provide an externally adjustable output current up to 1A for TSOT25 package and 1.5A for MSOP-8EP package. Depending upon supply voltage and external components, this converter can provide up to 40 watts output power.

The AL8860 integrates the power switch and a high-side output current sensing circuit, which uses an external resistor to set the nominal average output current.

Dimming can be realized by applying an external control signal to the CTRL pin. The CTRL pin will accept either a DC voltage signal or a PWM signal.

The soft-start time can be adjusted by an external capacitor from the CTRL pin to ground. Applying a voltage of 0.2V or lower to the CTRL pin can turn off the output and make the device enter standby state with low current consumption.

Feature(s)

• Low BOM Counts
• Wide Input Voltage Range: 4.5V to 40V
• Output Current up to 1.5A
• Internal 40V NDMOS Switch
• Typical 5% Output Current Accuracy
• Single Pin for On/Off and Brightness Control by DC Voltage or PWM Signal
• Recommended Analog Dimming Range: 5% to 100%
• Soft-Start
• High Efficiency (Up to 97%)
• LED Short Protection
• Inherent Open-Circuit LED Protection
• Overtemperature Protection (OTP)
• Up to 1MHz Switching Frequency
• Pb-Free TSOT25 and MSOP-8EP Packages
• Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
• Halogen and Antimony Free. “Green” Device (Note 3)
• An automotive-compliant part is available under separate datasheet (AL8860Q)

Application(s)

• LED retrofit for low voltage halogen
• Low voltage industrial lighting
• Illuminated signs
• External drivers with multiple channels