1:2 Differential LVPECL Fanout Buffer, SMA I/Os

SKU:

$ 1,305.25

Item	Description
88000102-4	Cable, triple voltage, with modular plugs, Length in ft.
88000103-4	Cable, triple voltage, with modular plug and pig tail leads, Length in ft.

Product Description
Diagrams
Applications
Specifications
Documents

Applications:

Fanout Single-ended Input signals into two pairs of Differential signals for driving long lines
Ideal for receiving signals from long lines
Fanout GHz Sinewave signals into two pairs of Differential LVPECL signals
1 PPS Distribution/IRIG-B Distribution
An Essential Lab Tool for Working with LVPECL Circuits

Features:

3 GHz f_MAX
Single-ended or Differential Inputs
Internal 50 Ω/V_TT Input Terminations also accept AC coupled Signals
Complementary Outputs drive 50 Ω loads terminated to V_TT, AC coupled or floating 50 Ω loads
DC Coupled I/Os Compatible with ECLinPS or 10KH Devices
SMA I/O Connectors
Ready-to-Use 1.3 x 2 9 x 2 2-in. Module includes a ±8.5 V AC/DC Adapter

Description

The PRL-431LP is a 1:2 Differential Fanout LVPECL Buffer module. It is an essential lab tools for applications where it is necessary to drive two different loads from a single source of single-ended or differential LVPECL signals. It can also be used for converting GHz sine wave signals into differential LVPECL 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/V_TT*, 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. The D input is switched internally to V_BB**, and termination resistor R_T for the D input is changed to 62 Ω. Complementary outputs of the PRL-431LP are designed for driving 50 Ω loads terminated into +1.3 V. With internal pull-down resistors, these outputs can also be AC-coupled for driving 50 Ω loads terminated to ground or to other voltages.

The PRL-431LP complementary outputs must be used together for driving differential LVPECL inputs only, because the reduced output logic swing of 400 mV_PP (for short circuit protection reasons) is not logic level compatible with some single-ended LVPECL inputs.

The PRL-431LP is housed in a 1.3 x 2.9 x 2.2-in. extruded aluminum enclosure and supplied with a ±8.5 V/1.8 A AC/DC Adapter.

V_TT is nominally -2.0 V for ECL, +3.0 V for PECL, and +1.3 V for LVPECL. V_BBis nominally -1.3 V for ECL, +3.7 V for PECL, and 2.0 V for LVPECL.

PRL-431LP Block Diagram

(0° C ≤ TA ≤ 35° C)*

Symbol	Parameter	PRL-431LP			UNIT
Symbol	Parameter	Min	Typ	Max	UNIT
R_IN	Input Resistance	49.5	50.0	50.5	Ω
V_TT	D Input Termination Voltage (fixed)	1.18	1.30	1.43	V
V_T1	D Input Termination Voltage	1.18	1.30	1.43	V
V_T2	D Input Termination Voltage (variable)	1.80	2.00	2.20	V
V_IL	Input Lo Voltage	1.35	1.48	1.67	V
V_IH	Input Hi Voltage	2.08	2.28	2.42	V
V_OL	Output Lo Voltage	1.35	1.48	1.61	V
V_OH	Output Hi Voltage	2.15	2.28	2.51	V
I_DC	DC Input Current		150	170	mA
V_DC	DC Input Voltage	7.5	8.5	12	V
V_AC	AC/DC Adapter Input Voltage	103	115	127	V
T_PLH	Propagation Delay to output ↑		750	950	ps
T_PHL	Propagation Delay to output ↓		750	950	ps
t_r/t_f⁽¹⁾	Rise/Fall Times (20%-80%)		220	300	ps
T_SKEW	Skew between Q & Q outputs		20	75	ps
F_MAX⁽²⁾	Max clock frequency	2.5	3.0		GHz
V_CMR	Common Mode Range	2.0		3.3	V
	Size	1.3 x 2.9 x 2.2			in.
	Weight, excluding AC adapter	5			Oz
	Shipping weight, excluding AC adapter	4			lb.

*All measurements are made with outputs terminated into 50 Ω/V_TT, using the PRL-550LPQ4X four channel LVPECL Terminator, connected to a 50 Ω input sampling oscilloscope.

Notes:

(1). The output rise and fall times are measured with both the Q and Q outputs terminated into 50 Ω/V_TT. An unused complementary output must be either terminated into 50 Ω/V_TT or AC coupled into a 50 Ω; otherwise, output waveform distortion and rise time degradation will occur. Use the PRL-550LPQ4X four channel LVPECL Terminator for the 50 Ω/+1.3 V termination and for connection of LVPECL signals to 50 Ω input oscilloscopes.

(2). f_MAX is measured by AC coupling a sine wave to the D input using the differential input mode (switch up). The differential outputs are first divided by four, using the PRL-255LP, and then measured using the PRL-550LPQ4X, four channel LVPECL Terminator, connected to a sampling scope.