Two-Stage Hysteretic LED Driver Controller
The RT8476 is a two-stage controller with dual gate drivers
consist of a Boost converter (first stage) and a Buck
converter (second stage). The advantage of the two-stage
topology is highly compatible with ET (Electronic
Transformer) in MR16 / AR111 lighting market field
The first stage is a Boost converter for constant voltage
output with inductor peak current over current protection.
The second stage is a Buck converter for constant output
current by typical constant peak current regulation.
The RT8476 is equipped with dual output gate drivers for
external power MOSFETs, suitable for higher power
The RT8476 is available in the SOP-8 and SOP-8 (Exposed
z MR16 Lighting
z Signage and Decorative LED Lighting
z Architectural Lighting
z High Power LED Lighting
z Low Voltage Industrial Lighting
z Indicator and Emergency Lighting
z Automotive LED Lighting
z Two-Stage Topology (Boost + Buck)
z Wide Input Voltage Range : 4.5V to 40V
z Adjustable Peak Input Current Control
z Adjustable Boost Output Voltage
z Independent Dual Stage Function
z Adjustable LED Current with ±5% LED Current
z Input Under Voltage Lockout Detection
z Thermal Shutdown Protection
z SOP-8 and SOP-8 (Exposed Pad) Packages
z RoHS Compliant and Halogen Free
S : SOP-8
SP : SOP-8 (Exposed Pad-Option 2)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Simplified Application Circuit
Copyright ©2013 Richtek Technology Corporation. All rights reserved.
DS8476-00 April 2013
is a registered trademark of Richtek Technology Corporation.