TI 公司的THS7319是集成了濾波器的非常低功耗的單電源(2.6V-5V)三路視頻放大器.THS7319集成了三路增強分辨率(ED)的濾波器,具有三階Butterworth特性.可用作DAC重建濾波器或ADC抗混淆濾波器.THS7319在3.3V時的總靜態電流僅為3.4mA,非常適合以電池為能源的應用,如PMP,數碼相機,手機視頻輸出緩沖和USB/手提低功耗視頻緩沖.本文介紹了THS7319主要特性,方框圖, 標準測試電路以及多種應用電路,包括單電源DC耦合輸入/DC耦合輸出視頻線路驅動器,DC耦合編碼器/DAC和DC耦合線路驅動器的THS7319系統, 驅動AC耦合視頻線路的DC輸入系統.此外還介紹了THS7319 EVM評估板電路圖和評估板材料清單.
Fabricated using the revolutionary, complementary Silicon-Germanium (SiGe) BiCom3X process, the THS7319 is a very low-power, 2.6-V to 5-V single-supply, three-channel, integrated filter video buffer. This device is ideal for battery-powered applications where size and power are critical parameters. Total quiescent current is only 3.4 mA at 3.3 V and can be reduced to 0.15 µA while disabled.
The THS7319 incorporates three enhanced definition (ED) filter channels with third-order Butterworth characteristics. These filters are useful as digital-to-analog converter (DAC) reconstruction filters or as analog-to-digital converter (ADC) anti-aliasing filters supporting 480p/576p YPBPR and RGB video. The THS7319 is also ideal for oversampled systems that produce standard-definition (SD) signals including CVBS, S-Video, 480i/576i YPBPR, YUV, and RGB.
The THS7319 is designed for dc-coupled inputs. To mitigate any DAC/encoder termination interaction, the input impedance is a very high 2.4 M. The 150-mV output level shift allows for a full sync dynamic range at the output with a 0-V input that prevents sync crushing. The rail-to-rail output stage supports both ac and dc line driving.
The THS7319 is offered in a RoHS-compliant ultra-small 9-ball MicrostarCSP package that measures 1.5-mm × 1.5-mm × 0.35-mm.
THS7319主要特性:
Very Low Total Quiescent Current: 3.4 mA at 3.3 V
0.15-µA Total Disabled Supply Current
Third-Order Butterworth Low-Pass Filters:
-1 dB at 17 MHz
-3 dB at 20 MHz
21-dB Attenuation at 43 MHz
Supports 480p/576p YPBPR or RGB Video
Supports CVBS, S-Video, 480i/576i YPBPR, or YUV in Oversampled Systems
DC-Coupled Input with 150-mV Output Shift
Built-in 6-dB Gain (2 V/V)
+2.6-V to +5-V Single-Supply Operation
Rail-to-Rail Output Allows AC or DC Output Coupling
Low Differential Gain/Phase of 0.05%/0.03°
Ultra-Small, 1.5-mm × 1.5-mm × 0.35-mm, MicrostarCSP™ 9-Ball Package
THS7319應用:
Personal Media Players
Digital Cameras
Cellular Phone Video Output Buffering
USB/Portable Low-Power Video Buffering
圖1.THS7319功能方框圖
圖2.THS7319標準測試電路
圖3.THS7319單電源DC耦合輸入/DC耦合輸出視頻線路驅動器
圖4.典型的THS7319系統:DC耦合編碼器/DAC和DC耦合線路驅動器
圖5.驅動AC耦合視頻線路的典型THS7319DC輸入系統
圖6.THS7319 EVM評估板電路圖
THS7319 EVM評估板材料清單(BOM):
