Datasheet

ManualsBrandsSTMICROELECTRONICS ManualsLinear ICsLinear IC - Amplifier - Video buffering 280 MHz SO 8

March 2007 Rev 4 1/17

TSH343

280MHz single-supply triple video buffer

Features

■ Bandwidth: 280MHz

■ 5V single-supply operation

■ Internal input DC level shifter

■ No input capacitor required

■ 6dB internal gain for a matching between 3

channels

■ Very low harmonic distortion

■ Slew rate: 780V/μs

■ Specified for 150Ω and 100Ω loads

■ Min. and max. data tested during production

Applications

■ High-end video systems

■ High definition TV (HDTV)

■ Broadcast and graphic video

■ Multimedia products

Description

The TSH343 is a triple single-supply video buffer

featuring an internal gain of 6dB and a large

280MHz bandwidth.

The main advantage of this circuit is that its input

DC level shifter allows for video signals on 75Ω

video lines without damage to the synchronization

tip of the video signal, while using a single 5V

power supply with no input capacitor. The DC

level shifter is internally fixed and optimized to

keep the output video signals between low and

high output rails in the best position for the

greatest linearity.

This datasheet provides information on using the

TSH343 as a Y-Pb-Pr driver for video DAC output

on a video line. See the TSH344 datasheet for R-

G-B signals.

The TSH343 is available in the compact SO8

plastic package for optimum space-saving.

Top View

OUT2

IN2

OUT1

+Vcc

OUT3

IN1

IN3

GND

SO8

Pin1 identification

DC Shifter

6dB

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Summary of content (17 pages)

PAGE 1
TSH343 280MHz single-supply triple video buffer Features ■ Bandwidth: 280MHz ■ 5V single-supply operation ■ Internal input DC level shifter ■ No input capacitor required ■ 6dB internal gain for a matching between 3 channels ■ Very low harmonic distortion ■ Slew rate: 780V/μs ■ Specified for 150Ω and 100Ω loads ■ Min. and max.
PAGE 2
TSH343 Contents 1 Absolute maximum ratings and operating conditions . . . . . . . . . . . . . 3 2 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3.1 Using the TSH343 to drive Y-Pb-Pr video components . . . . . . . . . . . . . . 10 3.2 PSRR and improvement of power supply noise rejection . . . . . . . . . . . . 12 3.
PAGE 3
TSH343 1 Absolute maximum ratings and operating conditions Absolute maximum ratings and operating conditions Table 1. Absolute maximum ratings (AMR) Symbol VCC Vin Parameter Supply voltage (1) Input voltage range (2) Value Unit 6 V 0 to +1.
PAGE 4
Electrical characteristics TSH343 2 Electrical characteristics Table 3. VCC = +5V single supply, Tamb = 25°C (unless otherwise specified) Symbol Parameter Test conditions Min. Typ. Max. 400 600 670 Unit DC performance VDC Input DC shift (see Figure 16 for the behaviour in temperature) RL = 150Ω, Tamb mV -40°C < Tamb < +85°C 530 Tamb , input to GND 18.2 -40°C < Tamb < +85°C 20.
PAGE 5
TSH343 Table 3. Electrical characteristics VCC = +5V single supply, Tamb = 25°C (unless otherwise specified) (continued) Symbol Parameter Test conditions Min. Typ. Max. Unit Noise and distortion F = 100kHz, RIN = 50Ω 29 nV/√Hz 10kHz to 30MHz 10kHz to 100MHz 158 290 μVrms 2nd harmonic distortion Vout = 2Vp-p, RL = 150Ω F= 10MHz F= 30MHz -58 -45 dBc 3rd harmonic distortion Vout = 2Vp-p, RL = 150Ω F= 10MHz F= 30MHz -72 -50 dBc eN Total input voltage noise HD2 HD3 1.
PAGE 6
Electrical characteristics Frequency response Figure 2. 10 6,20 8 6,15 6 6,10 4 6,05 Gain (dB) Gain (dB) Figure 1. TSH343 2 0 -2 -4 Gain flatness 6,00 5,95 5,90 5,85 -6 5,80 Vcc=5V Load=150Ω -8 -10 1M Vcc=5V Load=150Ω 5,75 10M 100M 5,70 1M 1G 10M Frequency (Hz) Figure 3. Cross-talk vs. frequency (amp1) Figure 4. 0 -10 1G Cross-talk vs.
PAGE 7
TSH343 Electrical characteristics Figure 7. Distortion on 150Ω load - 10MHz Figure 8. -30 -40 HD2 & HD3 (dBc) -45 -50 -30 Vcc=5V F=10MHz input DC component = 0.65V Load=150Ω -35 -45 -55 HD2 -60 Vcc=5V F=10MHz input DC component = 0.
PAGE 8
Electrical characteristics TSH343 Figure 13. Reverse isolation vs. frequency Figure 14. Bandwidth vs. temperature 0 500 Vcc=5V Load=100Ω -10 450 -20 400 -30 Bw (MHz) Gain (dB) -40 -50 -60 350 300 250 -70 200 -80 150 -90 -100 1M 10M 100 -40 100M Vcc=5V Load=150Ω -20 0 Frequency (Hz) 20 40 60 80 Temperature (°C) Figure 15. Quiescent current vs. supply Figure 16. Input DC shift vs.
PAGE 9
TSH343 Electrical characteristics Figure 19. Ibias vs. temperature Figure 20. Gain deviation vs. temperature 1,0 24 22 0,8 GD (%) IBIAS (μA) 20 18 16 Gain deviation between 0.3V and 1V input voltages Vcc=5V Load=150Ω 0,6 0,4 14 0,2 12 Vcc=5V Load=150Ω 10 -40 -20 0 20 40 60 0,0 -40 80 -20 0 Temperature (°C) 20 40 60 80 Temperature (°C) Figure 21. Supply current vs. temperature Figure 22. Output current vs.
PAGE 10
Application information TSH343 3 Application information 3.1 Using the TSH343 to drive Y-Pb-Pr video components Figure 25. Shapes of video signals coming from DACs White (100 IRE) 54ns (4t) 27ns (2t) 27ns (2t) 590ns (44t) 300mV 700mV Black (30 IRE) 300mV GND 1.030V 14.8µs (1100t): 1920*1080i 24.3µs (1800t): 1280*720i 590ns (44t) 10mV Synchronization tip •Fclock=74.25MHz •t=1/Fclock=13.5ns 0.330V (0 IRE) 0.030V time Amplitude 1Vp-p Frequency 30MHz Figure 26.
PAGE 11
TSH343 Application information Figure 27. Detailed view of one TSH343 channel STB +5V 600mV DC DAC + 75Ω 1/3 TSH343 (gain=2) 470nH TV video line 140Ω 75Ω 68pF -5V 68pF 0V 5Volt 5Volt 5Volt 3,22V 1,61V 1,01V 1,22V (10mV+600mV)*gain 610mV 10mV 0Volt 0Volt 0Volt Because of the shape of the signal shown in Figure 25, we use a very low output rail triple high-speed buffer. The TSH343 supplied in 5V single power supply, features a low output rail of 40mV on 150-ohm load.
PAGE 12
Application information 3.2 TSH343 PSRR and improvement of power supply noise rejection Figure 28. Circuit for power supply bypassing S R +5V T-bias L CLF AGILENT 4395A CHF 50Ω TSH343 A 75Ω Figure 29 shows how the power supply noise rejection evolves versus frequency depending on how carefully the power supply decoupling is achieved. Figure 29.
PAGE 13
TSH343 Delay between channels Figure 30. Measurement of the delay between each channel 5V 75Ω 600mV + +6dB 75Ω Cable V1 75Ω Vin 75Ω 600mV + +6dB 75Ω Cable V2 75Ω 75Ω 75Ω 600mV + +6dB 75Ω Cable V3 75Ω The delay between each video component is an important aspect in high definition video systems. To properly drive the three video components without any relative delay, the TSH343 dice layout has a very symmetrical geometry.
PAGE 14
Package mechanical data 4 TSH343 Package mechanical data In order to meet environmental requirements, STMicroelectronics offers these devices in ECOPACK® packages. These packages have a lead-free second level interconnect. The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK is an STMicroelectronics trademark.
PAGE 15
TSH343 Package mechanical data Figure 32. SO-8 package Dimensions Ref. Millimeters Min. Typ. A Inches Max. Min. Typ. 1.75 0.069 A1 0.10 A2 1.25 b 0.28 0.48 0.011 0.019 c 0.17 0.23 0.007 0.010 D 4.80 4.90 5.00 0.189 0.193 0.197 E 5.80 6.00 6.20 0.228 0.236 0.244 E1 3.80 3.90 4.00 0.150 0.154 0.157 e 0.25 Max. 0.004 0.010 0.049 1.27 0.050 h 0.25 0.50 0.010 0.020 L 0.40 1.27 0.016 0.050 k 1° 8° 1° 8° ccc 0.10 0.
PAGE 16
Ordering information 5 TSH343 Ordering information Table 4. Order codes Part number TSH343ID TSH343IDT 6 Package -40°C to +85°C SO-8 Packing Marking Tube TSH343I Tape & reel TSH343I Revision history Table 5. 16/17 Temperature range Document revision history Date Revision Changes 1-Dec-2005 1 First release of datasheet. 2-Jan-2006 2 Capa-load option paragraph deleted on page 11. 10-Jul-2006 3 Application information.
PAGE 17
TSH343 Revision history Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale.