AD8124 Triple Differential Receiver with 200 Meter Adjustable Cable Equalization

Applications

The AD8124 is a triple, high speed, differential receiver and equalizer that compensates for the transmission losses of UTP and coaxial cables up to 200 meters in length. Various gain stages are summed together to best approximate the inverse frequency response of the cable. Logic circuitry inside the AD8124 controls the gain functions of the individual stages so that the lowest noise can be achieved at short-to-medium cable lengths. This technique optimizes its performance for low noise, short-to-medium range applications, while at the same time provides the high gain bandwidth required for longer cable equalization (up to 200 meters). Each channel features a high impedance differential input that is ideal for interfacing directly with the cable.

The AD8124 has three control pins for optimal cable compensation, as well as an output offset adjust pin. Two voltage-controlled pins are used to compensate for different cable lengths; the VPEAK pin controls the amount of high frequency peaking and the VGAIN pin adjusts the broadband flat gain, which compensates for the low frequency flat cable loss.

For added flexibility, an optional pole adjustment pin, VPOLE, allows movement of the pole locations, allowing for the compensation of different gauges and types of cable as well as variations between different cables and/or equalizers. The VOFFSET pin allows the dc voltage at the output to be adjusted, adding flexibility for dc-coupled systems.

The AD8124 is available in a 6 mm × 6 mm, 40-lead LFCSP and is rated to operate over the extended temperature range of −40°C to +85°C.

Features and Benefits
  • Compensates cables to 200 meters for wideband video
    All resolutions through UXGA
  • Fast rise and fall times
    8 ns with 2 V step @ 200 meters of UTP cable
  • 37 dB peak gain at 100 MHz
  • Two frequency response gain adjustment pins
    High frequency peaking adjustment (VPEAK)
    Broadband flat gain adjustment (VGAIN)
  • Pole location adjustment pin (VPOLE)
    Compensates for variations between cables
    Can be optimized for either UTP or coaxial cable
  • DC output offset adjust (VOFFSET)
  • Low output offset voltage: 24 mV
  • Compensates both RGB and YPbPr
  • Two on-chip comparators with hysteresis
    Can be used for common-mode sync extraction
  • Available in 40-lead, 6 mm × 6 mm LFCSP
Audio & Video Products
Amplifiers
Data Sheets
Documentnote
AD8124: Triple Differential Receiver with 200 Meter Adjustable Cable Equalization Data Sheet (Rev. A)PDF 303 kB
Order Information
Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
AD8124ACPZ Production40 ld LFCSP (6x6mm w_4.3mm EP) OTH 490-40 to 85C6.735.95Y
AD8124ACPZ-R7 Production40 ld LFCSP (6x6mm w_4.3mm EP) REEL 750-40 to 85C05.95Y
AD8124ACPZ-RL Production40 ld LFCSP (6x6mm w_4.3mm EP) REEL 2500-40 to 85C05.95Y
Evaluation Boards
Part NumberDescriptionPriceRoHS
AD8124-EVALZEvaluation Board-1Y
AD8124: Triple Differential Receiver with 200 Meter Adjustable Cable Equalization Data Sheet (Rev. A) ad8124