**AD9883AKSTZ-110: A Complete Technical Overview of the 220 MSPS Interface Device**
The **AD9883AKSTZ-110** from Analog Devices is a high-performance, triple 8-bit analog interface device designed specifically for capturing and digitizing RGB graphics signals from personal computers and workstations. Optimized for resolutions from SXGA to UXGA and beyond, this integrated circuit (IC) is a cornerstone in applications requiring high-fidelity analog-to-digital conversion, such as **liquid crystal display (LCD) monitors, projectors, and advanced scan converters**.
At the heart of the AD9883's functionality is its trio of 220 Mega Samples Per Second (MSPS) analog-to-digital converters (ADCs). Each channel is dedicated to one component of the RGB signal, ensuring simultaneous sampling and maintaining precise phase relationships critical for accurate color reproduction. The device incorporates a proprietary sampling architecture that minimizes jitter, a vital factor for preserving signal integrity and reducing visual artifacts in the final digital output.
A key feature of the AD9883 is its integrated **Phase-Locked Loop (PLL)**. This on-chip PLL generates a high-quality, low-jitter sample clock directly from the incoming horizontal sync (HSYNC) signal. This eliminates the need for an external clock source, simplifies system design, and ensures the sampling clock is perfectly synchronized with the incoming analog video data. The PLL is highly programmable, allowing designers to lock onto a wide range of input resolutions and refresh rates with exceptional stability.
The device offers extensive programmability through an I²C serial interface. This allows for real-time adjustment of critical parameters, including:
* **Gain and Offset Control:** Each ADC channel has independent gain and offset adjust registers. This enables precise matching of the ADC's input range to the amplitude and DC offset of the incoming analog signal, maximizing the dynamic range and ensuring black-level accuracy.
* **Power Management:** The IC supports power-down modes, allowing for significant energy savings when the device is not in active use, a crucial feature for modern eco-friendly designs.
* **Sync Processing:** The AD9883 features robust sync processing circuitry to handle composite sync and sync-on-green (SOG) input signals, extracting clean timing references for the PLL and the system.
The analog input stage is designed for ease of use, featuring a 1.25V reference and accepting standard 0.5V to 1.0V analog input signals. It provides high impedance inputs, minimizing the load on the source. The digital outputs are TTL-compatible, facilitating easy connection to downstream logic, such as field-programmable gate arrays (FPGAs) or scaler chips.
Housed in a space-saving 80-lead LQFP package, the AD9883AKSTZ-110 operates from a single 3.3V power supply, streamlining power distribution within the end system. Its combination of high-speed performance, integrated features, and design flexibility has made it a historically significant and reliable solution for high-end video display applications.
**ICGOODFIND:** The AD9883AKSTZ-110 stands as a highly integrated and programmable solution, merging three high-speed ADCs with a precision PLL to deliver a complete analog interface subsystem. Its focus on **maintaining signal integrity**, simplifying design, and providing extensive user control solidified its position as a preferred component for professional and high-resolution display systems.
**Keywords:** **Analog-to-Digital Converter (ADC)**, **Phase-Locked Loop (PLL)**, **Signal Integrity**, **I²C Programmable**, **220 MSPS**.
