01-02-2013, 12:28 PM
LED Lighting Driver IC Introduction
1LED Lighting Driver.ppt (Size: 1.34 MB / Downloads: 272)
RT8456 Secondary-side constant Current Controller
Secondary side LED current regulation
Support LED voltage up to 45V
High accuracy LED current threshold control over wide input voltage and temperature range
0.6mA operation current
Programmable LED current through 60mV sense resister
Programmable OVP
Easily connected to different kinds of primary side solutions
TSOT 23-6
RT8457: Dimmable secondary side constant current controller
LED voltage up to 45V
Support Triac dimming, PWM dimming, analog dimming
High accuracy LED current threshold control over wide input voltage and temperature range
Programmable LED current through 60mV sense resister
Programmable OVP
Easily connected to different kinds of primary side solutions
SOP-8
RT8454 AC-CC 6-Ch Current Regulators
Vcc up to 50V
Programmable channel current
3% current sense amplifier input offset
Easy dimming
Programmable soft start and OVP
Automatic detecting unconnected AND/OR broken channel to avoid output over voltage
Vcc under voltage lockout and Thermal shutdown
One LDO controller embedded
Secondary side solution
RT8456, RT8457, RT8454 can work with any kind of primary side topologies and become constant current LED drivers except (6)
Maintain current accuracy at +/-5% independent of the variation of transformer
Non-dimmable: Primary side + RT8456
Dimmable: (bleeder)+ Primary side + RT8457
Support Triac dimming with external bleeder added
Support PWM, analog, wireless… dimming on secondary side with accurate current control.
Using MCU for Traic dimming can provide the best compatibility of dimmer.