LYTSwitch-4 ECAD Models
- Better than ±5% Constant Current (CC) Regulation
- Power Factor Correction (PFC) for Low-Line Applications
- TRIAC Dimming and Non-Dimming Options
High Performance, Combined Driver, Controller, Switch
The LYTSwitch-4 family enables off-line LED drivers with high power factor which easily meet international requirements for THD and harmonics. Output current is tightly regulated with better than ±5% CC tolerance1. Efficiency of up to 92% is easily achieved in typical applications.
Supports a Wide Selection of TRIAC Dimmers
The LYTSwitch-4 family provides excellent turn-on characteristics for leading-edge and trailing-edge TRIAC dimming applications. This results in drivers with a wide dimming range and fast start-up, even when turning-on from a low conduction angle. Large dimming ratio and low "pop-on" current.
Low Solution Cost and Long Lifetime
LYTSwitch-4 ICs are highly integrated and employ a primary-side control technique that eliminates the optoisolator and reduces component count. This allows the use of low-cost single-sided printed circuit boards. Combining PFC and CC functions into a single-stage also helps reduce cost and increase efficiency. The 132 kHz switching frequency permits the use of small, low-cost magnetics.
LED drivers using the LYTSwitch-4 family do not use primary-side aluminum electrolytic bulk capacitors. This means greatly extended driver lifetime, especially in bulb and other high temperature applications.
- Fast start-up
- <250 ms at full brightness
- <1s at 10% brightness
- High power factor >0.9
- Easily meets EN61000-3-2
- Less than 10% THD in optimized designs
- Up to 92% efficient
- 132 kHz switching frequency for small magnetics
|Part Number||Input Voltage Range||TRIAC Dimmable|
|Low-Line Output Power Table2|
|LYT4x11E/L5||2.5 W||12 W|
|LYT4x12E/L||2.5 W||15 W|
|LYT4x13E/L||3.8 W||18 W|
|LYT4x14E/L||4.5 W||22 W|
|LYT4x15E/L||5.5 W||25 W|
|LYT4x16E/L||6.8 W||35 W|
|LYT4x17E/L||8.0 W||50 W|
|LYT4x18E/L||18 W||78 W|
Table 1. Low-Line Output Power Table.
|High-Line Output Power Table2|
|LYT4x21E7||6 W||12 W|
|LYT4x22E||6 W||15 W|
|LYT4x23E||8 W||18 W|
|LYT4x24E||9 W||22 W|
|LYT4x25E||11 W||25 W|
|LYT4x26E||14 W||35 W|
|LYT4x27E||19 W||50 W|
|LYT4x28E||33 W||78 W|
Table 2. High-Line Output Power Table.
- Performance for typical design. See Applications Note.
- Continuous power in an open-frame design with adequate heat sinking; device local ambient of 70 °C. Power level calculated assuming a typical LED string voltage and efficiency >80%.
- Minimum output power requires CBP = 47 μF.
- Maximum output power requires CBP = 4.7 μF.
- LNK4311 CBP = 47 μF, LNK4211 CBP = 4.7 μF.
- Package: eSIP-7C(E), eSIP-7F(L).
- LYT4321 CBP = 47 µF, LYT4221 CBP = 4.7 µF.
- Package: eSIP-7C