## Overview of the AD8128ACPZ-R2 The **AD8128ACPZ-R2** is a high-speed, differential receiver and equalizer designed by Analog Devices. It is specifically engineered to compensate for the transmission losses that occur when sending high-resolution video or high-speed data over long lengths of Unshielded Twisted Pair (UTP) cables (like Cat5 or Cat6). --- ### Technical Specifications The following table highlights the core electrical characteristics of the device: | Parameter | Specification | | :--- | :--- | | **Type** | Differential Receiver / Equalizer | | **Bandwidth** | 380 MHz | | **Slew Rate** | 1200 V/µs | | **Cable Compensation** | Up to 300 meters (Cat5) | | **Supply Voltage Range** | 4.5V to 5.5V | | **Package** | LFCSP-8 (3mm x 3mm) | | **Mounting Type** | Surface Mount | --- ### Key Internal Components & Functions 1. **Equalization Network**: The heart of the chip is a variable frequency-response filter. It applies a "boost" to high-frequency signals that have been attenuated by the skin effect and dielectric losses of the cable. 2. **V_PEAK Control**: It features a control pin (VPEAK) that allows the user to adjust the amount of high-frequency equalization based on the length of the cable. 3. **Common-Mode Rejection**: As a differential receiver, it is highly effective at rejecting common-mode noise and interference, which is critical for maintaining signal integrity in long-distance transmissions. 4. **Low Noise Floor**: Designed for video applications, it maintains a low noise profile to prevent "snow" or artifacts in the displayed image. --- ### Pinout Configuration (LFCSP-8) | Pin # | Name | Function | | :--- | :--- | :--- | | 1 | **IN+** | Non-inverting Differential Input | | 2 | **IN-** | Inverting Differential Input | | 3 | **V_PEAK** | Equalization Control Voltage | | 4 | **V-** | Negative Power Supply (Ground) | | 5 | **VOUT** | Single-Ended Output Signal | | 6 | **V+** | Positive Power Supply (+5V) | | 7 | **REF** | Reference Voltage Input | | 8 | **PAD** | Exposed Thermal Pad (Connect to V-) | --- ### Application Scenarios * **KVM (Keyboard, Video, Mouse) Extenders**: Sending VGA/RGB signals over Ethernet cables. * **CCTV Systems**: Transmitting analog video over long distances without high-cost coaxial cables. * **Digital Signage**: Distribution of video signals across large commercial spaces.