PRL-444LV, 4 Channel TTL/CMOS to LVDS Level Translator and Line Driver

Applications:

• TTL to LVDS Logic Level Translation
• Conversion of Single-Ended TTL Signals to Differential Signals for Driving Long Lines
• Mini Modular Instrument for interfacing with High Speed Data Communications Equipment

Features:

• 250 MHz Typical Maximum Clock Rate
• 4 Single Ended Inputs with Selectable 50 Ω or 1 kΩ Termination
• 4 LVDS Outputs for Driving 50 Ohm or Cat 7 Cables into 100 Ω Floating Loads
• SMA or RJ45 I/O Connectors
• Single Supply, +7.5 VDC to +12 VDC, operation
• Ready-to-Use 1.3 x 2.9 x 2.9-in. Module includes a ±8.5 V/1.4 A AC/DC Adapter

Description

The PRL-444LV is a 4 Channel TTL to LVDS translator module. The input resistance of the inputs can be selected to be either 50 Ω or 1 kΩ by a common toggle switch. The 1 kΩ inputs are desirable when interfacing with low power circuits. The four pairs of complementary outputs are designed for driving floating 100 Ω loads, normally the configuration used in LVDS input circuits. The output swing is typically 300 mV with a common mode voltage of 1.0 V.

All I/Os are DC coupled and have SMA or RJ45 connectors, as part numbers PRL-444LV-SMA and PRL-444LV-RJRJ, respectively. A block diagram showing the equivalent input and output circuits are shown in Figs. 1 and 2. Cat7 or better cabling is recommended for RJ45 models, as the double shielding improves the impedance control. See our case studies on single-ended impedance and differential impedance of standard, off-the-shelf network cabling. 

The modules are housed in a 1.3 x 2.9 x 2.9-in. extruded aluminum enclosure and supplied with a ±8.5 V/±1.4 A, auto-switching AC/DC Adapter. Either model may also be ordered without the power supply by appending “-OEM” to the part number, e.g. PRL-444LV-SMA-OEM. A maximum of four units can share one PRL-760D-120/220 AC/DC adapter, using additional units of cable #88000102-4. If mounting is desired, a pair of the #35001420 mounting brackets can accommodate any two PRL modules of the same length. Please refer to the Accessories section for more detail.

A complementary product, the PRL-425QLT, performs the opposite conversion of 4 LVDS signals to 4 TTL signals, and the PRL-RJ45-SMA adapter can be used to adapt Cat7 network cabling to SMA or the reverse.