NCS37012: Single CT UL943 GFCI with Self Test

The NCS37012 is a fully UL943 compliant signal processor for GFCI applications with self test. The device integrates a flexible power supply (including both shunt and LDO regulators), differential fault, and grounded-neutral detection circuits. Proprietary impedance measurement and signal processing techniques are used to minimize the number of external components and improve performance. The device also includes a specialized DSP controller that offers best in class immunity to nuisance loads without the need for external analog filters. Self-test is monitored every 17 minutes through an external current path and internally generated grounded neutral fault.

Features
  • full self test and trip indicator monitoring
  • self syncing internal oscillator adjusts to AC mains frequency to guarantee full resolution on 50 and 60Hz distribution systems
  • randomized testing sequence to noise sensitivity and potential interactions on the AC mains
  • high SCR drive current (up to 5mA)
Benefits
  • fully compliant with UL self test requirements and minimal BOM impact
  • compatible with global AC power systems
  • robust design
  • compatible with high Igt SCR's for improved noise immunity
Applications
  • UL943 compliant GFCI products
End Products
  • GFCI receptacles
  • GFCI circuit breakers
  • GFCI power cords
Data Sheets (1)
Document TitleDocument ID/SizeRevisionRevision Date
Ground Fault Circuit Interrupter (GFCI) with Self TestNCS37012/D (95kB)0May, 2016
Package Drawings (2)
Document TitleDocument ID/SizeRevision
QFN16, 3x3, 0.5P485G (57.3kB)F
TSSOP 20, 6.5x4.4948AD (52.2kB)revo
Order Information
ProductStatusCompliancePackageMSL*ContainerBudgetary Price/Unit
NCS37012DBRGActivePb-free Halide freeTSSOP-20948AD3Tape and Reel2500$0.8
NCS37012MNTWGActivePb-free Halide freeQFN-16Contact BDTIC3Tape and Reel3000$0.8
Specifications
ProductChannelsVCC Min (V)VCC Max (V)IT Max (mA)VI Typ (V)TA Min (°C)TA Max (°C)
NCS37012DBRG16122.21.8-4085
NCS37012MNTWG16122.21.8-4085
Ground Fault Circuit Interrupter (GFCI) with Self Test (95kB) NCS37012
QFN16, 3x3, 0.5P NCS37012
TSSOP 20, 6.5x4.4 NCS37012