The PRL-434A is a 1:4 Differential NECL Fanout Buffer module.
It is intended for fanning out single-ended or differential NECL signals
into four pairs of differential outputs. It can also be used for converting
AC coupled GHz sinewave or PECL signals into differential ECL signals.
A switch selects either single-ended or differential inputs,
as shown in Fig. 1. In the differential
input mode, both inputs D and D
are terminated internally into 50 Ω/-2 V, and, therefore, either one or
both inputs can accept AC-coupled signals as well. In the single input mode,
signal should be connected to the D input only. Input
D is switched internally
to VBB, nominally -1.3 V, and termination resistor RT
for the D input channel is
changed to 62 Ω. Complementary outputs of the PRL-434, with internal pull
down resistors, can drive either 50 Ω loads terminated into -2 V, or AC-coupled
or floating 50 Ω loads.
The PRL-434A is housed in a 1.3 x 2.9 x 2.9-in. extruded
aluminum enclosure and is supplied with a ±8.5 V/1.4 A AC/DC Adapter.
The PRL-434A is an improved model of the discontinued
PRL-434. It has faster rise/fall times,
a higher fMAX and a redesigned mechanical layout with all the
outputs on the same side of the unit. The PRL-434A is recommended for all