2 Ch. Translator, TTL to PECL

SKU:

$ 1,130.45

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:

Converting TTL/CMOS signals to Differential PECL Signals
High Speed Digital Communications system testing
High Speed SONET Clock Level Translation
Converting TTL/CMOS Clocks to PECL Clocks for connection to Transient Recorders

Features:

f_MAX > 300 MHz
1100 ps t_r
50 Ω TTL/CMOS Input
1.5 V or 1.0 V Selectable Input Threshold
Complementary PECL Outputs
BNC Input, SMA Output Connectors
DC-Coupled I/Os
Self-contained 1.3 x 2.9 x 3.9-in. units including AC/DC Adapters

Description

The PRL-420PD translator converts TTL/CMOS logic to PECL levels.

Each unit has a switch-selectable 1.5 V or 1 V input threshold voltage, with a 50 Ω fixed input termination. The complementary PECL outputs from the PRL-420PD are suitable for driving 50 Ω loads terminated to +3 V. The outputs of all units can also drive AC-coupled or floating 50 Ω loads.

These Logic Level Translators are designed specifically for use in testing and interfacing of high speed digital communications circuits, where conversions from TTL/CMOS level signals to PECL level signals are often required. They are ideal building blocks that complement other PRL Logic Level Translators, such as the PRL-450ND, PRL-450PD, PRL-460NPD and PRL-460PND, etc. in systems integration applications where interconnections of mixed logic signals are often necessary.

They are ready-to-use functional modules housed in 1.3 x 2.9 x 3.9-in. extruded aluminum enclosures and are supplied with ±8.5V AC/DC Adapters. All units have BNC input connectors and SMA output connectors. A block diagrams is shown in Fig. 1.

If mounting is desired, a pair of 35001420 mounting brackets can accommodate two PRL modules of the same length. A number of PRL modules can also share a single ±8.5V AC/DC adapter using the PRL-730 or PRL-735 voltage distribution module.

Fig. 1, PRL-420PD Block Diagram

(0° C ≤ T_A ≤ 35° C)*

Symbol	Parameter	PRL-420PD			Unit
Symbol	Parameter	Min	Typ	Max	Unit
R_IN	Input Resistance	49.5	50	50.5	Ω
R_OUT	Output Resistance	49.5	50	50.5	Ω
V_TOSH	Input Threshold Voltage (High)	1.4	1.5	1.6	V
V_TOSL	Input Threshold Voltage (Low)	0.9	1.0	1.1	V
V_OL	Output Low Level	3.2	3.4	3.5	V
V_OH	Output High Level	3.9	4.1	4.3	V
I_DC1	DC Input Current, +8.5 V		180	200	mA
I_DC2	DC Input Current, -8.5 V		-315	-335	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 ↑		2		ns
t_PHL	Propagation Delay to output ↓		2		ns
t_r/t_f⁽¹⁾	Rise/Fall Times (20%-80%)		1100	1250	ps
t_SKEW1	Skew: V_O↑↔V_O↓		200	500	ps
t_SKEW2	Skew: V_O1↑↔ V_O2↑		200	500	ps
f_MAX⁽²⁾V_TOSH	Max Clock Frequency Input Threshold Voltage (High)	200	300		MHz
f_MAX⁽²⁾V_TOSL	Max Clock Frequency Input Threshold Voltage (Low)	300	400		MHz
	Size	1.3 x 2.9 x 3.9			in.
	Weight, excl. AC adapter	7			Oz
	Shipping weight, incl. AC adapter	4			lb.

*Unless otherwise specified, dynamic measurements are made with all outputs terminated into 50 Ω /-2 V for PRL420ND and 50 Ω/3 V for PRL-420PD.

Notes:

The output rise and fall times are measured with with all inputs terminated into 50 Ω/V_TT. For best performance all outputs should be terminated into 50 Ω/V_TT or else AC- coupled into 50 Ω loads. If a single output is used, its complement must be terminated; otherwise output waveform distortion will occur. If one pair of complementary outputs is used, the other complementary pair may remain unterminated. Use the PRL-550PQ4X, four channel PECL Terminator, for the 50 Ω/V_TT termination and for connection of PECL signals to 50 Ω input oscilloscopes. The PRL-ACT-50, Dual Channel AC-Coupled 50 Ω Terminator, may also be used to provide the 50 Ω/V_TT termination. If preservation of DC levels is not required, then the PRL-SC-104, 0.1 µf DC block or a 12 dB AC-coupled attenuator may be used to connect the PECL outputs to 50 Ω input instruments.

(2). f_MAX for the PRL-420PD is measured using the PRL-450PD as the input driver, and its outputs are connected to the differential inputs of the PRL-255P PECL frequency divider. The outputs of the PRL 255P are then measured using the PRL-550PQ4X, four channel PECL Terminators, connected to a 50 Ω input sampling 'scope.

While we believe these models to be accurate, no representations are made as to accuracy or suitability for any application: