AD9985A: 110 MSPS/140 MSPS Analog Interface for Flat Panel Displays

The AD9985A is a complete 8-bit, 140 MSPS, monolithic analog interface optimized for capturing RGB graphics signals from personal computers and workstations. Its 140 MSPS encode rate capability and full power analog bandwidth of 300 MHz support resolutions up to SXGA (1280 × 1024 at 75 Hz).

The AD9985A includes a 140 MHz triple ADC with internal 1.25 V reference, a PLL, and programmable gain, offset, and clamp control. The user provides only a 3.3 V power supply, analog input, and horizontal sync (Hsync) and Coast signals. Three-state CMOS outputs can be powered from 2.5 V to 3.3 V.

The AD9985A’s on-chip PLL generates a pixel clock from the Hsync input. Pixel clock output frequencies range from 12 MHz to 140 MHz. PLL clock jitter is 500 ps p-p typical at 140 MSPS. When the COAST signal is presented, the PLL maintains its output frequency in the absence of Hsync. A sampling phase adjustment is provided. Data, Hsync, and clock output phase relationships are maintained.

The AD9985 also offers full sync processing for composite sync and sync-on-green applications, variable analog input bandwidth control, variable SOGIN bandwidth control and selectable input filtering.

A clamp signal is generated internally or can be provided by the user through the CLAMP input pin. This interface is fully programmable via a 2-wire serial interface.

Fabricated in an advanced CMOS process, the AD9985A is provided in a space-saving 80-lead LQFP surface-mount Pb-free plastic package, and is specified over the –40°C to +85°C temperature range.

产品应用领域 Applications

• RGB graphics processing
• LCD monitors and projectors
• Plasma display panels
• Scan converters
• Microdisplays
• Digital TVs

AD9985A 特点

• Automated clamping level adjustment
• 140 MSPS maximum conversion rate
• 300 MHz analog bandwidth
• 0.5 V to 1.0 V analog input range
• 500 ps p-p PLL clock jitter at 110 MSPS
• 3.3 V power supply
• Full sync processing
• Sync detect for hot plugging
• Midscale clamping
• Power-down mode
• Low power: 500 mW typical
• 4:2:2 output format mode

AD9985A 功能框图

AD9985A 芯片订购指南

产品型号	产品状态	封装	引脚	温度范围
AD9985A/PCBZ	量产	评估板	80	商业
AD9985ABSTZ-110	量产	80 ld LQFP (14x14mm)	80	工业
AD9985AKSTZ-110	量产	80 ld LQFP (14x14mm)	80	商业
AD9985AKSTZ-140	量产	80 ld LQFP (14x14mm)	80	商业

AD9985A 应用技术支持与电子电路设计开发资源下载

1. AD9985A 数据手册DataSheet 下载 . PDF
2. ADI 模拟器件公司比较器产品选型指南 . PDF
3. Analog Devices, Inc. 美国模拟器件公司产品订购手册 .PDF