2 Ch. LVPECL to LVDS Translator

SKU:

$ 1,138.50

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Product Description
Diagrams
Applications
Specifications
Documents

Applications:

Converting Single Ended or Differential LVPECL Signals to LVDS Signals
Converting TTL signals to LVDS
High Speed Digital Communications systems Testing
High Speed SONET Clock Level Translation

Features:

fmax > 500 MHz for NECL/PECL input, 300 MHz for TTL
1.1 ns Typical Output Rise & Fall Times
Single Ended or Differential 50 Ω/V_TT Inputs (NECL/PECL)
Switchable 1.5 V/1.0 V input threshold (TTL)
Complementary 50 Ω LVDS Outputs
SMA I/O Connectors for NECL/PECL; BNC Inputs for TTL
Triax Output connectors for PRL-426NTR, PRL-426PTR, and PRL-426TTR
Two channels for CLK/DATA translation
Self-contained 1.3 x 2.9 x 3.9-in. units include ±8.5 V/1.4 A AC/DC Adapters

Description

The PRL-426 is a series of NECL-, PECL- or TTL-to-LVDS Logic Level Translators:

PRL-426N converts NECL to LVDS
PRL-426P converts PECL to LVDS
PRL-426T converts TTL to LVDS.

The PRL-426N/426P can receive either single-ended or differential input signals, selected by a switch. The input connectors on the PRL-426N/426P are SMA.

On the PRL-426T, the input is single-ended only, and the switch controls the input threshold (1.5 V or 1.0 V into 50 Ω). The input connectors on the PRL-426T are BNC.

The differential outputs are 50 Ω back-terminated and are designed for driving floating 100 Ω loads, normally the configuration used in LVDS input circuits. The output swing is typically 600 mV with a common mode voltage of 1.2 V. The PRL-426NTR, PRL-426PTR, and PRL-426TTR have Triax output connectors instead of the SMA connectors. These high speed translators facilitate testing of high speed digital communications circuits where conversion of NECL/PECL clock and data signals to LVDS level signals is often required.

The PRL-426N is designed to interface with -5.2 V or -3.3 V NECL circuits and the PRL-426P with +5 V PECL circuits. In the differential input mode, both inputs D and D of the PRL-426N are terminated into 50 Ω/-2 V, and those of the PRL-426P into 50 Ω/3 V. 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. The D inputs are switched internally to V_BB, nominally -1.3 V for the PRL-426N and 3.7 V for the PRL-426P, and termination resistors R_T's for the D input channels are changed to 62 Ω.

The PRL-426T is designed to interface with TTL circuits. In cases where the signal source cannot drive TTL voltages into 50 Ω, the input threshold switch can be used to change the triggering voltage to 1.0 V.

Each unit is supplied with a ±8.5 V/1.4 A AC/DC Adaptor and housed in a 1.3 x 2.9 x 3.9-in. extruded aluminum enclosure. Available accessories include voltage distribution modules for mounting multiple units.

Fig. 1: PRL-426NTR Dual Ch. NECL to LVDS Translator, Triax Outputs

Fig. 2: PRL-426T Dual Ch. TTL to LVDS Translator

Fig. 3: PRL-426N Dual Ch. NECL to LVDS Translator, SMA I/Os

(0° C ≤ T_A ≤ 35° C)*

Symbol	Parameter	PRL-426N			PRL-426P			PRL-426T			UNIT
Symbol	Parameter	Min	Typ	Max	Min	Typ	Max	Min	Typ	Max	UNIT
R_in	Input Resistance	49.5	50	50.5	49.5	50	50.5	49.5	50	50.5	Ω
R_out	Output Resistance	49.5	50	50.5	49.5	50	50.5	49.5	50	50.5	Ω
V_TT	"D" Input Termination Voltage (fixed)	-2.2	-2.0	-1.8	2.7	3.0	3.3		N/A		V
V_T	"D" Input Termination Voltage (variable)	-1.17/ -2.2	-1.3/ -2.0	-1.43/ -1.8	3.33/ 2.7	3.7/ 3.0	4.07/ 3.3		N/A		V
V_OL	Output Low Level		0.9			0.9			0.9		V
V_OH	Output High Level		1..5			1.5			1.5		V
V_CMV	Common Mode Voltage¹		1.2			1.2			1.2		V
I_DC	DC Input Current		85/ -300	100/ -330		150/ -250	175/ -300		100/ -205	110/ -215	mA
V_DC	DC Input Voltage	±7.5	±8.5	±12	±7.5	±8.5	±12	±7.5	±8.5	±12	V
V_AC	AC/DC Adapter Input Voltage	103	115	127	103	115	127	103	115	127	V
t_PLH	Propagation Delay to output ↑		2			2			2		ns
t_PHL	Propagation Delay to output ↓		2			2			2		ns
t_r/t_f	Rise/Fall Times² (10%-90%)		1	1.25		1	1.25		1	1.25	ns
t_SKEW	Skew between any two outputs		200	500		200	500		200	500	ps
f_max	Maximum Clock Frequency	500	625		500	625		250	300		MHz
	Size	1.3 x 2.9 x 3.9			1.3 x 2.9 x 3.9			1.3 x 2.9 x 3.9			in.
	Weight	7			7			7			Oz

Notes:

(1) V_CMV = (V_oH-V_oL)/2

(2) Rise and Fall times are measured with SMA output connector units only and with ground-referenced 50 Ω loads.

(3) fmax is measured using a PRL-425N with the corresponding input connectors as the receiver. The NECL outputs of the PRL-425N are measured. f_max for the PRL-426T is currently limited by the lack of high frequency TTL drivers.

Units with the Trompeter CBBJR79 Triax ouput connectors are tested using the PRL-425NTR, Universal Differential Receiver (Triax) with Differential NECL outputs, and the Trompeter PCGOW10PCG-36 shielded twisted pair cables.

All PRL products with Triax connectors use Trompeter P/N CBBJR79, Right Angle Circuit Board Bulkhead Jack, 3-lug (Numbered page 10, document page 11 of 142). Any Trompeter 70-series Triax Cable Plug with 3 lugs (e.g. PL75-9, 3-lug) will mate with CBBJR79.