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
IN2 2
6dB
Pin1 identification
Top View
IN1 1
6dB
8 OUT1
7 OUT2
Applications
■
■
■
■
High-end video systems
High definition TV (HDTV)
Broadcast and graphic video
Multimedia products
IN3 3
DC Shifter
6dB
6 OUT3
5 GND
+Vcc 4
SO8
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.
March 2007
Rev 4
1/17
www.st.com
17
TSH343
Contents
1
2
3
Absolute maximum ratings and operating conditions . . . . . . . . . . . . . 3
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1
3.2
3.3
Using the TSH343 to drive Y-Pb-Pr video components . . . . . . . . . . . . . . 10
PSRR and improvement of power supply noise rejection . . . . . . . . . . . . 12
Delay between channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4
5
6
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Ordering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
2/17
TSH343
Absolute maximum ratings and operating conditions
1
Absolute maximum ratings and operating conditions
Table 1.
Symbol
V
CC
V
in
T
oper
T
stg
T
j
R
thjc
R
thja
P
max
ESD
Supply voltage
(1)
Input voltage range
(2)
Operating free air temperature range
Storage temperature
Maximum junction temperature
SO8 thermal resistance junction to case
SO8 thermal resistance junction to ambient area
Maximum power dissipation (@T
amb
=25°C) for T
j
=150°C
CDM: charged device model
HBM: human body model
MM: machine model
Absolute maximum ratings (AMR)
Parameter
Value
6
0 to +1.4
-40 to +85
-65 to +150
150
28
157
800
2
1.5
200
Unit
V
V
°C
°C
°C
°C/W
°C/W
mW
kV
kV
V
1. All voltage values, except differential voltage, are with respect to network terminal.
2. The magnitude of input and output voltages must never exceed V
CC
+0.3V.
Table 2.
Symbol
V
CC
Operating conditions
Parameter
Power supply voltage
Value
3 to 5.5
(1)
Unit
V
1. Tested in full production at 0V/5V single power supply.
3/17
Electrical characteristics
TSH343
2
Table 3.
Symbol
Electrical characteristics
V
CC
= +5V single supply, T
amb
= 25°C (unless otherwise specified)
Parameter
Test conditions
Min.
Typ.
Max.
Unit
DC performance
Input DC shift
(see
Figure 16
for the behaviour in
temperature)
Input bias current
Input resistance
Input capacitance
Supply current per buffer
-40°C < T
amb
< +85°C
Power supply rejection ratio
(1)
20 log (ΔV
out
/ΔV
CC
)
DC voltage gain
Variation of the DC voltage gain
between inputs of 0.3V and 1V
Gain matching between 3 channels
Gain matching between 3 channels
F = 1MHz
R
L
= 150Ω, V
in
= 1V
Input step from 0.3V to 1V
Input = 1V
Input = 0.3V
1.92
14.9
-45
1.99
0.26
0.5
0.5
2.05
0.8
2
2
dB
V/V
%
%
%
R
L
= 150Ω T
amb
,
-40°C < T
amb
< +85°C
T
amb
, input to GND
-40°C < T
amb
< +85°C
T
amb
T
amb
no load, input to GND
I
CC
PSRR
G
DG
MG
1
MG
0.3
400
600
530
18.2
20.7
4
1
14.4
18
mA
35
μA
GΩ
pF
670
mV
V
DC
I
ib
R
in
C
in
Dynamic performance and output characteristics
-3dB bandwidth
Bw
Gain flatness @ 0.1dB
FPBW
D
SR
V
OH
V
OL
Full power bandwidth
Delay between each channel
(2)
Slew rate
(3)
High level output voltage
Low level output voltage
Output current
I
OUT
Output short-circuit current (I
source
)
Small signal V
out
= 20mVp
R
L
= 150Ω
Small signal V
out
= 20mVp
R
L
= 150Ω
V
out
= 2V
p-p
, V
ICM
= 0.5V,
R
L
= 150Ω
0 to 30MHz
Input step from 0V to 1V,
R
L
= 150Ω
V
in DC
= +1.5V, R
L
= 150Ω
R
L
= 150Ω
V
out
= 2V, T
amb
-40°C < T
amb
< +85°C
45
500
3.7
130
160
280
MHz
65
200
0.5
780
3.9
40
90
mA
82
100
mA
MHz
ns
V/μs
V
mV
4/17
TSH343
Table 3.
Symbol
Noise and distortion
F = 100kHz, R
IN
= 50Ω
eN
Total input voltage noise
10kHz to 30MHz
10kHz to 100MHz
V
out
= 2V
p-p
, R
L
= 150Ω
F= 10MHz
F= 30MHz
V
out
= 2Vp-p, R
L
= 150Ω
F= 10MHz
F= 30MHz
Electrical characteristics
V
CC
= +5V single supply, T
amb
= 25°C (unless otherwise specified) (continued)
Parameter
Test conditions
Min.
Typ.
Max.
Unit
29
158
290
-58
-45
-72
-50
nV/√
Hz
μVrms
HD2
2nd harmonic distortion
dBc
HD3
3rd harmonic distortion
dBc
1. See
Figure 28
and
Figure 29.
2. See
Figure 30
and
Figure 31.
3. Non-tested value, guaranteed by design.
5/17
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
