LYT7504D

The LYTSwitch™-7 family is ideal for single-stage, high PF, constant current LED dimmable applications.

The family incorporates a high-voltage MOSFET with a variable on-time CrM controller. Extensive protection features with minimum external components provide industry leading power density and functionality.

The CrM operation results in low turn-on losses and reduces cost of output diode (slower reverse recovery).

LYTSwitch-7 devices are suitable for applications from 4 W to 22 W. See Graph 1 for selection guidance based on typical inductance. LYTSwitch-7 peak current mode operation is suitable for TRIAC applications without the need of an active bleeder.

Product Highlights

Single-Stage PFC + Accurate CC Output

• ±3% CC regulation in single line input voltage applications
• Power factor >0.9
• High efficiency >85%
• Robust 725 V MOSFET for increased line voltage surge performance
• Critical Conduction Mode (CrM) buck
• Low EMI
• Excellent line noise and transient rejection

Dimming Highlights

• Fast turn-on (<500 ms)
• Low pop-on
• Better than 10:1 dimming ratio
• Simple passive R-C damper
• Monotonic dimming response

Design Flexibility

• Wide input (90 VAC – 308 VAC) and output voltage range operation
• LYT7503D and LYT7504D both cover power range for optimum device selection
• Requires no inductor bias winding
• Small form factor package – SO-8

Highest Reliability

• Industries lowest component count dimming solution
• Comprehensive protection features with auto-restart
  • Input and output overvoltage protection (OVP)
  • Output short-circuit protection
  • Open-loop protection
• Advanced thermal control
  • Thermal foldback ensures that light continues to be delivered at elevated temperatures
  • Over-temperature shutdown provides protection during fault conditions