DescriptionThe 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 new applications. |