The NCT6683D-T is a member of Nuvoton’s eSIO series, combining the built-in microcontroller and the traditional legacy SIO functions. The NCT6683D-T supports an industrial standard 1T 8-bit microcontroller, and 16 Kbyte SRAM. The firmware code is stored in an external SPI flash and could be updated via LPC interface or  special tools provided by Nuvoton.

The NCT6683D-T monitors several critical parameters in PC hardware, including power supply voltages, fan speeds and temperatures. In terms of temperature monitoring, the NCT6683D-T adopts the Current Mode (dual current source) and thermistor sensor approach. The NCT6683D-T also supports the hardwired Smart Fan control system, including SMART FAN™ I and SMART FAN™ IV, which makes the system more stable and user-friendly. Some hardware monitor peripherals are also supported, such as SMBus master/slave, Intel^® PECI and AMD^® SB-TSI interface.

The NCT6683D-T supports traditional super IO functions, including LPC interface, Printer Port, 2 UART, KBC, and flexible I/O control functions through a set of general purpose I/O (GPI/O) ports.

In addition, the NCT6683D-T implements some specific features that provide customers more benefits, such as power saving control function to further reduce the power consumption while the system is at S5 state, Consumer IR for remote control, Port 80 decode via LPC interface for debug purpose, two-color LED to indicate the current power state.