RT8458 PWM Buck LED驱动器应用电路

TheRT8458is aPWMcontroller with an integrated high side floating gate driver. It is used for step down converters by well controlling the external MOSFET and regulating a constant output current.

The output duty cycle of theRT8458can be up to 100% for wider input voltage application, such as E27 and PAR30 off-lineLEDlighting products.

Features
• Low Cost and Efficient Buck Converter Solution
• Universal Input Voltage Range with Off-Line Topology
• Programmable Constant LED Current
• Dimmable LED Current by ACTL
• Output LED String Open Protection
• Output LED String Short Protection
• Output LED String Over Current Protection
• Built-in Thermal Protection
• TSOT-23-6 Package
• RoHS Compliant and Halogen Free

Application
• E27, PAR30, Offline LED Lights

Pin Configurations

TSOT-23-6

Typical Applications Circuit

Figure 1. For Typical Application

Figure 2. For High PF Application