ST TSH120视频缓冲放大方案

ST公司的 TSH120是视频缓冲放大器,包括有内部增益为6dB的电压负反馈放大器,轨到轨输出,输入偏置和SAG修正.内部还有能衰减27MHz寄生的重建滤波器. TSH120有非常低的功耗,可提供待机模式,工作电压从2.2V到5.5V,主要用于照相手机,数码相机,数字摄像机和STB与DVD视频输入.本文介绍了TSH120的主要特性, 带输出电容和不带输出电容的电路图, TSH120评估板电路图以及评估板材料清单(BOM).

The TSH120 is a video buffer that includes a voltage feedback amplifier with an internal gain of 6dB, rail-to-rail output, internal input biasing and SAG correction. A power down function offers a sleep mode with ultra low consumption. The TSH120 also features an internal reconstruction filter in order to attenuate the parasitic 27MHz frequency from the clock of the video DAC.

TSH120主要特性:
■Very low consumption
■Standby mode available
■Internal reconstruction filter
■Internal gain of 6dB
■Rail-to-rail output
■Tested with +2.5V and +3.3V single supply
■Operation supply from +2.2V to +5.5V
■SAG correction
■Excellent video performance
Differential gain 0.5%
Differential phase 0.5°
Group delay=10ns
■Specified for 150load
■Input DC level shifter
■Min. and max. limits are tested in full production

TSH120应用:
■Camera phones
■Digital still camera
■Digital video camera
■Set-top box and DVD video outputs



图1.TSH120带输出电容的电路图



图2.TSH120不带输出电容的电路图

基于TSH120的带SAG修正的视频缓冲器和滤波器
Video buffer and filter with SAG correction based on the TSH120
This evaluation board is based on the TSH120 video buffer. The TSH120 includes a voltage feedback amplifier with an internal gain of 6 dB, rail-to-rail output, internal input biasing and SAG correction. A power-down function provides a sleep mode with ultra low power consumption.

TSH120评估板特性:
■Very low consumption in active and standby mode
■Internal reconstruction filter
■Internal gain of 6 dB
■Rail-to-rail output
■Operating supply voltage from +2.2 V to +5.5 V
■SAG correction
■Excellent video performance
Differential gain: 0.5 %
Differential phase: 0.5°
■Group delay=10 ns
■Specified for 150 load
■Input DC level shifter



图3.TSH120评估板外形图




图4.TSH120评估板电路图
TSH120评估板材料清单(BOM):