2 Ch. Translator, TTL to NECL

Applications:

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

Features:

• f_MAX > 300 MHz
• 750 ps t_r
• 50 Ω TTL/CMOS Input
• 1.5 V or 1 V Selectable Input Threshold
• Complementary NECL Outputs
• BNC Input Connector
• SMA or Triax Output Connectors
• DC-Coupled I/O's
• Self-contained 1.3 x 2.9 x 3.9-in. units including AC/DC Adapters

Description

The PRL-420ND translator converts TTL/CMOS logic to NECL levels.

Each unit has a switch-selectable 1.5 V or 1.0 V input threshold voltage with a fixed 50 Ω input termination. The complementary NECL outputs from the PRL-420ND are suitable for driving 50 Ω loads terminated to -2 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 NECL 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. The TTL input connector is BNC. The NECL output connectors can be SMA or Triax. Block diagrams is shown in Fig. 1A and 1B.

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.