2 Ch. Translator, NECL to PECL, 2 GHz


$ 1,236.25


  • Converting Single Ended or Differential LVPECL Signals to Differential NECL Signals
  • High Speed Digital Communications systems Testing
  • High Speed SONET Clock Level Translation


  • fmax > 1.25 GHz
  • 750 ps tr
  • 50 Ω/VTT Input Terminations
  • Single Ended or Differential Inputs
  • Complementary NECL Outputs drive 50 Ω/-2V Terminations, AC-coupled or Floating 50 Ω Loads
  • DC coupled I/O's with SMA Connectors
  • Self-contained 1.3 x 2.9 x 2.9-in. unit including an AC/DC Adapter


The PRL-460ALPND is a dual channel LVPECL to NECL Logic Level Translator module, intended for operation from DC to the GHz range. Maximum clock frequency is typically 1.5 GHz. These modules can receive either single-ended or differential input signals, to be selected by a switch.

The complementary outputs of these modules are designed for driving 50 Ω loads terminated to -2 V, and they can also drive AC coupled or floating 50 Ω loads. These high speed translator modules facilitate testing and integration of high speed digital communications circuits and systems, where conversion of signals from LVPECL to NECL logic families is often required.

The PRL-460ALPND inputs are designed to interface with LVPECL circuits operating with a +3.3 V supply. In the differential input mode, both inputs D and D are terminated into 50 Ω/VTT, where VTT is +1.3V for LVPECL. In this mode, either one or both inputs can accept AC-coupled signals as well. In the single-input mode, signals should be connected to the D inputs only. Inputs D are switched internally to VBB, nominally +2 V for LVPECL, and termination resistors RT's for the D input channels are changed to 62 Ω. A block diagram of the PRL-460ALPND is shown in Fig. 1.

The PRL-460ALPND is supplied with a ±8.5 V AC/DC Adapter and housed in a 1.3 x 2.9 x 2.9-in. extruded aluminum enclosure.

Fig. 1 PRL-460ALPND Block Diagram

(0° C ≤ TA ≤ 35° C)*

Symbol Parameter PRL-460ALPND Unit
Min Typ Max
Rin Input Resistance 49.5 50 50.5
Rout Output Resistance (NPN emitter with 200 Ω pulldown)   N/A  
VTT "D" Input Termination Voltage (fixed) 1.18 1.30 1.43 V
VT "D" Input Termination Voltage (variable) 1.18/
VoL Output Low Level -1.85 -1.7 -1.55 V
VoH Output High Level -1.0 -0.8 -0.7 V
Vop-p Output Voltage Swing, f ≤ 700 MHz
Output Voltage Swing, f ≤ 550 MHz
IDC DC Input Current   +90
VDC DC Input Voltage ±7.5 ±8.5 ±12 V
VAC AC/DC Adapter Input Voltage 103 115 127 V
tPLH Propagation Delay to output ↑   1.25   ns
tPHL Propagation Delay to output ↓   1.25   ns
tr/tf Rise/Fall Times (20% - 80%)*   750 950 ps
tSKEW Skew between any 2 outputs   50 120 ps
fmax Max Clock Frequency 1.25 1.5   GHz
  Size 1.3 x 2.9 x 2.9 in.
  Weight 7 Oz
* An unused complementary output must be either terminated into 50 Ω/VTT or AC coupled into a 50 Ω load; otherwise, output waveform distortion and rise time degradation will occur. Use the PRL-ACT-50 dual channel AC coupled 50 Ω Termination for terminating unused complementary outputs and the PRL-SC-104 DC Block or PRL-ACX-12dB AC coupled attenuator for connection of NECL signals to 50 Ω input oscilloscopes, if DC information is not needed. Otherwise, use the PRL-550NQ4X four channel NECL Terminators for the 50 Ω/VTT termination and for connection of NECL signals to 50 Ω input oscilloscopes.