cupoftea
Advanced Member level 5
Hi
Regarding offline Quasi Resonant Flyback LED driver IC’s.
Its very noticeable that there are none available which provide facility to dim the LEDs down to <1W, when max power is 25W+.
This I am sure you would agree, is because the switching frequency of QR Flybacks gets far too high when they are only providing low output power….and conducted EMC regulations get tougher at >150kHz.
For example, the power integrations LYTswitch range does not have wide dimming facility...
www.power.com
..neither does any other QR LED driver
Regarding offline Quasi Resonant Flyback LED driver IC’s.
Its very noticeable that there are none available which provide facility to dim the LEDs down to <1W, when max power is 25W+.
This I am sure you would agree, is because the switching frequency of QR Flybacks gets far too high when they are only providing low output power….and conducted EMC regulations get tougher at >150kHz.
For example, the power integrations LYTswitch range does not have wide dimming facility...
LYTSwitch-6 | Power Integrations, Inc.
The LYTSwitch™-6 series family of ICs dramatically simplifies the development and manufacturing of off-line LED drivers, particularly those in compact enclosures or with high efficiency requirements. The LYTSwitch-6 architecture is revolutionary in that the devices incorporate both...
..neither does any other QR LED driver