SLOC™ (Security Link Over Coax) is a transmission protocol for simultaneously transmitting analog CVBS video and digital IP video over a single coaxial cable. The TW3811 is the receiving end of a SLOC link, converting the single SLOC signal on the coaxial cable back to separate Ethernet digital video data and analog CVBS video. It can be embedded into a DVR to enable one or more SLOC inputs or configured as a stand-alone SLOC-to-IP+CVBS converter. The TW3811 includes an AFE, digital modem, and two Ethernet MII/RMII interfaces. The device accepts a SLOC output signal from a SLOC transmitter and decodes it into an analog CVBS signal and an Ethernet MII signal.


  • Simultaneous transmission of IP video data and analog CVBS video over up to 500m of RG59 coaxial cable
  • Analog CVBS video preview support
  • Proprietary adaptive analog equalizer for extending the reach of CVBS video
  • Proprietary SLOC-based IP camera detection
  • Creates a full-duplex 100BASE-T digital link
  • 36Mbps downlink speed from TW3801 to TW3811
  • 4Mbps uplink for SLOC compliance
  • Ethernet MAC MII/RMII interface for interfacing to DVR/NVR network processor SoC
  • Optional Ethernet PHY MII/RMII interface for interfacing to external Ethernet PHY chip
  • I2C 2-wire control interface
  • Integrated PLL with 25MHz crystal interface
  • 1.8V, 3.3V supplies
  • 100-TQFP (12x12mm) Package


  • Single-Channel SLOC receiver modem
  • Multi-Channel SLOC receiver modem
  • Embedded DVR

tuneProduct Options

Part Number Part Status Pkg. Type Carrier Type MOQ Buy Sample
Active TQFP Tray 119
Active TQFP Reel 1000


Title language Type Format File Size Date
Datasheets & Errata
star TW3811-C1 Datasheet Datasheet PDF 980 KB
Application Notes & White Papers
AN1804: SLOC Design Guide Application Note PDF 1.10 MB
PIN19028 - Q3 Cy 19 Price Increase Notice Price Increase Notice PDF 208 KB