Texas Instruments Announces Ground Fault Circuit Interrupter (GFCI) With Self-Test and Neutral-Ground Fault Detection

Texas Instruments AFE3010

Texas Instruments has announced the AFE3010 – a precision, low-power, Ground Fault Circuit Interrupter (GFCI) controller used for detecting ground fault leakage paths in electrical circuits. This device is a single IC solution that continuously monitors an electrical circuit for multiple fault conditions to verify that the system is operating correctly.

Texas Instruments - AFE3010

In addition to a ground fault leakage detection, the AFE3010 can detect a grounded neutral condition which can also lead to a harmful shock from a connected appliance. The device implements a unique closed-loop grounded neutral detection scheme that eliminates the need for component resonance tuning, resulting in optimized system development time. Periodic self-test is performed once in every 180 cycles of the AC power line to ensure all the components related to ground fault control system are working properly. In case of any component failure the device enables an LED light, and/ or trips a solenoid to open the load switch. In applications where an LED light indicator is not needed, the ALARM pin can be configured as a secondary SCR driver to drive an additional solenoid for redundancy purpose.

The AFE3010 integrates shunt and LDO regulators to directly power from an AC line through a diode bridge and passive components.

The AFE3010 offers flexible configurable options to implement robust application specific protection schemes in different end-equipments such as electrical receptacles, circuit breakers, and so forth.

GFCI Application
GFCI Application.

Features

  • Single-chip GFCI controller to aid in the design of UL-943 compliant systems
    • Built-in self-test to detect end-of-life, blink the LED, and/ or trip the load switch
    • Detect ground fault leakage path, and trip the load switch
    • Detect neutral-ground leakage path, and trip the load switch
  • Protection against single-component failure
  • Dual VDD and GND pins for redundancy
  • Integrated noise filter to prevent false trips
  • Simultaneously protects against HOT to GND and neutral to GND faults
  • Adjustable fault current thresholds through external feedback resistors
  • Fast response time
    • 150 ms for ±5-mA ground fault current
    • 85 ms for ±10-mA ground fault current
    • 40 ms for ±30-mA ground fault current
    • 10 ms for ±50-mA ground fault current
  • Onboard shunt regulator powers the system through passives
  • Supports 120-V/ 60-Hz or 220-V/ 50-Hz systems
  • Operating temperature range: –40 °C to 105 °C

Applications

  • GFCI Outlet Receptacles
  • GFCI Circuit Breakers
  • Power Cord (In-Line GFCI)
  • Hair Dryer
  • Dish Washer
The AFE3010 Evaluation Board
The AFE3010 Evaluation Board.