Power Integrations LYTSwitch-3 Single-Stage LED Driver ICs

Power Integrations LYTSwitch-3 Single-Stage LED Driver ICs are ideal for single-stage power factor corrected constant current LED bulbs and downlighters. The LYTSwitch-3 family supports design flexibility with a buck, buck-boost, tapped buck-boost, boost, isolated, and non-isolated flyback up to 20W output. The ICs incorporate a high-voltage power MOSFET, discontinuous mode, and variable frequency on-time controller. The controller provides cycle-by-cycle current limit, output OVP, line overvoltage, comprehensive protection features, plus advanced thermal management circuitry.

Features

Supports buck, buck-boost, tapped buck-boost, boost, isolated and non-isolated flyback
Up to 20W output
No electrolytic bulk capacitors or optoisolators for increased lifetime
Comprehensive protection features
Input and output overvoltage
Output short-circuit and open-loop protection
Advanced thermal control

Thermal foldback ensures that light continues to be delivered at elevated temperatures
End-stop shutdown provides protection during fault conditions
Ensures monotonic VA reduction with TRIAC phase angle
Detects leading-edge and trailing-edge TRIAC dimmers
High-efficiency mode when no dimmer is present
Selectable dimming profile increases design flexibility
Low pop-on and dead-travel
Active bleeder drive for widest dimmer compatibility

Specifications

Low THD, 15% typical for dimmable bulbs, as low as 7% in optimized designs
Power Factor of >0.9
Up to 20W output
Less than ±3% CC regulation over line and load
Fast turn-on (<500ms)
On-time ranges
- 5.75µs to 6.75µs maximum
- 0.95µs to 1.15µs minimum
Temperatures
- -40°C to +150°C operating range
- -65°C to +150°C storage range
- +260°C lead
1.76kHz frequency jitter modulation rate

40kHz to 132.7kHz output frequency range with 8% peak-to-peak jitter
FEEDBACK Pin
- 291mV to 309mV voltage range
- 600mV triggering cycle skipping
- 2000mV overvoltage threshold
- 22mV undervoltage threshold
BYPASS Pin
- -11.5mA to -4.0mA charge current range
- 4.75V to 5.25V range
- 5.1V to 5.5V shunt voltage range at 5mA
- 4.4V to 4.8V power-up reset threshold voltage
0.8mA to 1.6mA DRAIN supply current range