The DS21448 is a quad‑port E1 or T1 line interface unit (LIU) for short‑haul and long‑haul applications, integrating four independent transmitters and receivers in a 144‑pin PBGA or 128‑pin LQFP package. It operates from a 3.3 V supply and supports both 75 Ω and 120 Ω line terminations.
Key features include software‑selectable receive‑side termination, jitter attenuation using a crystal‑less design, multiple line build‑out options, and support for Intel or Motorola parallel bus modes. The device also provides JTAG boundary‑scan testing, PRBS generation/detection, and a variety of loopback modes for diagnostics.
| Supply Voltage | 3.3 V |
|---|---|
| Operating Temperature Range (PBGA) | 0°C to +70°C |
| Operating Temperature Range (LQFP) | -40°C to +85°C |
| Package Types | 144‑pin PBGA or 128‑pin LQFP |
| Supported Line Impedances | 75 Ω or 120 Ω |
| Clock Output Frequencies | 16.384 MHz, 8.192 MHz, 4.096 MHz, 2.048 MHz |
The device operates from a 3.3 V supply.
It is offered in a 144‑pin PBGA or a 128‑pin LQFP package.
It supports internal software‑selectable receive‑side termination for 75 Ω, 100 Ω, or 120 Ω.