1:10 TTL Fanout Buffer/Line Driver


$ 1,121.25


  • TTL/CMOS Clock Distribution
  • 1:10 Fanout Line Driver
  • High Speed Digital Communications System Testing
  • 1 PPS Distribution/IRIG-B Distribution
  • Mini Modular Instrument


  • fmax > 100 MHz
  • Drives 100 ft of cable @ 80 MHz
  • 1.8 ns Typical Output Rise & Fall Times
  • 2.5 V into 50 Ω Typical
  • TTL Compatible 50 Ω or 10 kΩ Input
  • Ten in-phase 50 Ω TTL Outputs
  • Active Low EN (Enable) Input
  • BNC or SMA I/O Connectors
  • DC Coupled I/Os
  • Self-contained 3.0 x 6.8 x 4.0-in. unit includes an AC/DC Adapter


The PRL-4110 is a 1:10 fanout, 50 Ω TTL Line Driver. It is intended for distribution of high-speed clock and logic signals to multiple loads via long lines. The 50 Ω back-terminated outputs can drive long lines with or without 50 Ω load terminations. With 50 Ω load terminations, however, all outputs of the PRL-4110 can drive 100 ft of 50 Ω cables at clock rates greater than 80 MHz.

The input resistance of the PRL-4110 can be selected to be either 50 Ω or 10 kΩ by a switch. The 10 kΩ-input is desirable when interfacing with low power circuits. The 50 Ω back terminated outputs typically deliver 2.5 V into 50 Ω or 5.0 V into Hi-Z loads. All I/Os are DC coupled and have BNC or SMA connectors.

The unit also has a TTL-compatible EN input pulled down via a 1 kΩ resistor. When left open the Enable is active, and the fanout buffer will output signals. The unit can be disabled by driving its EN input high.

The PRL-4110 is housed in a 3.0 x 6.8 x 4.0-in. extruded aluminum enclosure and is supplied with the PRL-760C, ±8.5 V/±1.8 A AC/DC Adapter. The two DC power jacks are bussed together internally, allowing a second PRL-4110 to be daisy-chained from a single AC adapter. Two units can share a single PRL-760B adapter provided that the clock rate is 100 MHz or slower.

A block diagram showing the equivalent input and output circuits of the PRL-4110 is shown in Fig. 1.

Related Products:

  • PRL-4220, 2:20 Fanout 50 Ω TTL Line Driver, equivalent to two PRL-4110 units in a single enclosure
  • PRL-4330, 3:30 Fanout 50 Ω TTL Line Driver, equivalent to three PRL-4110 units in a single enclosure
  • PRL-4122, 1:22 Fanout 50 Ω TTL Line Driver, equivalent to one PRL-414B driving two PRL-4110 units in a single enclosure

(0° C ≤ TA ≤ 35° C)*

Symbol Parameter Min Typ Max Unit Comments
RIN LO Input Resistance Low Range 49.5 50 50.5
RIN HI Input Resistance High Range 9.9 10.0 10.1
RIN EN Input Resistance, Enable   1   kΩ  
ROUT Output Resistance   50    
VIL TTL Input Low Level -0.5 0.0 0.5 V  
VIH TTL Input High Level 2.0 2.4 5.0 V  
VIL EN EN Input Low Level -0.5 0.0 0.5 V  
VIH EN EN Input High Level 2.0 2.4 5.0 V Drive EN High to disable output
VOL TTL Output Low Level 0.0 0.25 0.5 V RL=50 Ω
VOH1 TTL Output High Level 2.2 2.5   V RL=50 Ω @ DC
VOH2 TTL Output High Level 4.4 5.0   V RL=1 MΩ @ DC
IDC1 DC Input Current   500   mA F =50 MHz sq. wave(1)
IDC2 DC Input Current   615   mA F ≤ 100 MHz
IDC3 DC Input Current     725 mA F =125 MHz
VDC DC Input Voltages 7.75 8.50 12.00 V  
VAC AC/DC Adapter Input Voltage 103 115 127 V  
TPLH Propagation Delay to output ↑   9 12 ns  
TPHL Propagation Delay to output ↓   9 12 ns  
tr Rise Time (10%-90%)   1.8 2.5 ns f =50 MHz sq. wave
tf Fall Time (10%-90%)   1.5 2.5 ns f =50 MHz sq. wave
TSKEW Skew between any 2 outputs   500 900 ps f =50 MHz sq. wave
FMAX1 Max. Clock Frequency(2) 100 125   MHz RG58C/U, cable length =3 ft
FMAX2 Max. Clock Frequency(3)   80     RG58C/U, cable length = 100 ft
PWMIN1 Minimum Pulse Width   4   ns ↑ Input
PWMIN2 Minimum Pulse Width   6   ns ↓ Input
  Size 3.0 x 6.8 x 4.0 in  
  Weight 1.5 lb Excluding AC adapter
  Shipping Weight 6.0 lb Including AC adapter
1. fMAX should not exceed 125 MHz, otherwise damage of the unit due to overheating may result.
2. fMAX2 is measured by driving a second PRL-4110 at the end of a 100 ft cable.
3. For sharing a single PRL-760C, ±8.5 V, ±1.8 A AC/DC adapter, the total current should not exceed 1.8 A.