MT773XH is a high precision constant current LED driver operating in critical conduction mode (CRM). It’s mainly targeted for non-isolated buck LED power systems.

MT773XH is suitable for applications with 85Vac~265Vac input voltage range. MT773XH integrates 500V power MOSFET. With innovative internal high voltage power supply solution, no external VCC capacitor and startup resistor are needed, which achieves simplified peripheral circuits and low BOM cost.

The high precision and fast current sensing circuit can support high frequency switch operation and get excellent line regulation. The system operates in CRM which makes the output current insensitive to the inductance and keeps good load regulation.

MT773XH provides various protections to improve the system reliability, including short circuit protection (SCP), thermal adjustment, etc.


  • No VCC capacitor and startup resistor
  • Supports high frequency switch operation, SMD inductor can be used.
  • Critical Conduction Mode, insensitive to the inductance.
  • No flicker at low line voltage
  • Highly accurate constant LED current±5%
  • LED short circuit protection
  • Under-voltage lockout (UVLO) protection
  • Thermal regulation function
  • Available in SOP4 package