电子产品世界

The RT8482 is a current mode PWM controller designed to drive an external MOSFET for high current LED applications. With a current sense amplifier threshold of 190mV, the LED current is programmable with one external current sense resistor. With a maximum operating input voltage of 36V and output voltage up to 48V, the RT8482 is ideal for buck, boost or buck-boost operation.
With 350kHz operating frequency, the external inductor and capacitors can be small while maintaining high efficiency.
Dimming can be either analog or PWM digital. The unique built-in clamping comparator and filter allow easy low noise analog dimming conversion from PWM signal with only one external capacitor.
The RT8482 is available in WQFN-16L 3x3 and SOP-16 packages.


Features
• High Voltage Capability : VIN Up to 36V, VOUT Up to 48V
• Buck, Boost or Buck Boost Operation
• Current Mode PWM with 350kHz Switching Frequency
• Easy Dimming : Analog, PWM Digital or PWM Converting to Analog with One External Capacitor
• Programmable Soft Start to Avoid Inrush Current
• Programmable Over Voltage Protection
• VIN Under Voltage Lockout and Thermal Shutdown
• 16-Lead WQFN and SOP Packages
• RoHS Compliant and Halogen Free

Application
• General Industrial High Power LED Lighting
• Desk Lights and Room Lighting
• Building and Street Lighting
• Industrial Display Backlight


Pin Configurations
( VIEW)

SOP-16

WQFN-16L 3x3

Typical Applications Circuit

Figure 1. Analog Dimming in Boost Configuration

Figure 2. PWM to Analog Dimming in Boost Configuration

Figure 3. Analog Dimming in Buck-Boost Configuration

Figure 4. Analog Dimming in Buck Configuration