美信集成產(chǎn)品公司的MAX9526是低功耗高性能NTSC/PAL視頻譯碼器,支持所有的NTSC和PAL標(biāo)準(zhǔn),包括NTSC M, NTSC J, NTSC 4.43,PAL B/G/H/I/D, PAL M, PAL N, PAL 60,自動進(jìn)行配置和標(biāo)準(zhǔn)選擇,具有真正的10位數(shù)字處理的10位4x過取樣(54MSPS)ADC,以及靈活的輸出格式,模擬和數(shù)字工作電壓1.8V,數(shù)字I/O電源為1.7V到3.45V,工作溫度從-40℃到125℃.可用在汽車娛樂系統(tǒng),防碰撞系統(tǒng),安全監(jiān)測/CCTV系統(tǒng)以及電視.本文介紹了MAX9526的主要特性,方框圖, 多個MAX9526視頻輸入處理框圖,帶電源隔離的MAX9526應(yīng)用電路和典型應(yīng)用電路。

Low-Power, High-Performance NTSC/PAL Video Decoder

The MAX9526 is a low-power video decoder that converts NTSC or PAL composite video signals to 8-bit or 10-bit YCbCr component video compliant with the ITUR BT.656 standard. The device powers up in fully operational mode and automatically configures itself to decode the detected input standard. The MAX9526 typically consumes 200mW of power in normal operation and typically less than 100μW in shutdown mode.

An internal 10-bit, 54MHz analog-to-digital converter (ADC) samples the input with four times oversampling. The MAX9526 features a DC restoration circuit with offset correction and automatic gain control to accurately optimize the full-scale range of the ADC.

An integrated analog anti-aliasing filter eliminates the need for external filtering. The MAX9526 includes a 2:1 input multiplexer with automatic signal selection based on activity at the inputs.

An internal line-locked phase-locked loop (PLL) generates the sample clock and the line-locked clock (LLC) output to provide an ITU-compliant output. Alternatively, the PLL can be configured to provide a sample clock and output clock at 2x and 1x the frequency of the crystal oscillator, respectively.

The MAX9526 provides a multiline adaptive comb filter to reduce cross-chrominance and cross-luminance artifacts. A single 1.8V supply is used for both the digital and analog supplies. The digital outputs operate from a separate +1.7V to +3.45V supply to allow direct connection to a wide range of digital processors. The MAX9526 operates over the -40℃ to +125℃ automotive temperature range and is available in both a 28-pin QSOP and a 32-pin TQFN (5mm x 6mm).

MAX9526主要特性:

Supports All NTSC and PAL Standards

NTSC M, NTSC J, NTSC 4.43,PAL B/G/H/I/D, PAL M, PAL N, PAL 60

Easy to Configure and Operate with Only 16 User-Programmable Registers

Automatic Configuration and Standard Select

10-Bit 4x Oversampling (54Msps) ADC with True 10-Bit Digital Processing

Flexible Output Formatting

10-Bit Parallel ITU-R BT.656 Output with Embedded TRS

8-Bit Parallel ITU-R BT.656 Output with Separate HS and VS

+1.8V Digital and Analog Supply Voltage

+1.7V to +3.45V Digital I/O Supply Voltage

Full Automotive Temperature Range (-40℃ to +125℃)

Low-Power Modes Shutdown (< 100μW typ)

Sleep Mode with Continuous Activity Detection (< 5mW typ)

2-to-1 Video Input Mux with AGC

MAX9526應(yīng)用:

Automotive Entertainment Systems

Collision Avoidance Systems

Security Surveillance/CCTV Systems

Televisions

圖1.MAX9526功能方框圖

圖2.多個MAX9526視頻輸入處理框圖

圖3.帶電源隔離的MAX9526應(yīng)用電路

圖4.MAX9526典型應(yīng)用電路