|
|
PDF LT1204 Data sheet ( Hoja de datos )
| Número de pieza | LT1204 | |
| Descripción | 4-Input Video Multiplexer with 75MHz Current Feedback Amplifier | |
| Fabricantes | Linear Technology | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de LT1204 (archivo pdf) en la parte inferior de esta página. Total 20 Páginas | ||
|
No Preview Available !
FEATURES
s 0.1dB Gain Flatness > 30MHz
s Channel Separation at 10MHz: 90dB
s 40mV Switching Transient, Input Referred
s – 3dB Bandwidth, AV = 2, RL = 150Ω: 75MHz
s Channel-to-Channel Switching Time: 120ns
s Easy to Expand for More Inputs
s Large Input Range: ± 6V
s 0.04% Differential Gain, RL = 150Ω
s 0.06° Differential Phase, RL = 150Ω
s High Slew Rate: 1000V/µs
s Output Swing, RL = 400Ω: ±13V
s Wide Supply Range: ±5V to ±15V
APPLICATI S
s Broadcast Quality Video Multiplexing
s Large Matrix Routing
s Medical Imaging
s Large Amplitude Signal Multiplexing
s Programmable Gain Amplifiers
LT1204
4-Input Video Multiplexer
with 75MHz Current
Feedback Amplifier
DESCRIPTIO
The LT®1204 is a 4-input video multiplexer designed to
drive 75Ω cables and easily expand into larger routing
systems. Wide bandwidth, high slew rate, and low differ-
ential gain and phase make the LT1204 ideal for broadcast
quality signal routing. Channel separation and disable
isolation are greater than 90dB up to 10MHz. The channel-
to-channel output switching transient is only 40mVP-P,
with a 50ns duration, making the transition imperceptible
on high quality monitors.
A unique feature of the LT1204 is its ability to expand into
larger routing matrices. This is accomplished by a patent
pending circuit that bootstraps the feedback resistors in
the disable condition, raising the true output impedance of
the circuit. The effect of this feature is to eliminate cable
misterminations in large systems.
The large input and output signal levels supported by the
LT1204 when operated on ±15V supplies make it ideal for
general purpose analog signal selection and multiplexing.
A shutdown feature reduces the supply current to 1.5mA.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATI
VIN0 1 VIN0 +1
75Ω
2
GND
VIN1 3 VIN1 +1
75Ω
4
GND
VIN2
5
VIN2
+1
75Ω
6
GND
VIN3 7 VIN3 +1
75Ω
8
REF
–15V
6.8k 8.2k
+
CFA
–
V+ 16 15V
VO 15
V– 14 –15V
FB 13
75Ω
VOUT
RF
1k RG
1k
LOGIC
S/D 12
ENABLE 11
A1 10
A0 9
LT1204
1204 TA01
All Hostile Crosstalk
Surface Mount PCB Measurements
– 20
VS = ±15V
VIN 0 = GND
–40 VIN 1,2,3 = 0dBm
RL = 100Ω
– 60
– 80
– 100
– 120
1
10
FREQUENCY (MHz)
100
1204 TA02
1
1 page  
WU
TYPICAL AC PERFOR A CE Measurements taken from SO Demonstration Board #028.
VS (V)
± 15
± 12
±5
± 15
± 12
±5V
± 15
± 12
±5
AV
1
1
1
2
2
2
10
10
10
RL (Ω)
150
1k
150
1k
150
1k
150
1k
150
1k
150
1k
150
1k
150
1k
150
1k
RF (Ω)
1.1k
1.6k
976
1.3k
665
866
787
887
750
845
590
649
866
1k
825
931
665
750
RG (Ω)
None
None
None
None
None
None
787
887
750
845
590
649
95.3
110
90.9
100
73.2
82.5
SMALL SIGNAL
– 3dB BW (MHz)
88.5
95.6
82.6
90.2
65.5
68.2
75.7
82.2
71.9
77.5
58.0
62.1
44.3
47.4
43.5
46.3
37.2
39.3
SMALL SIGNAL
0.1dB BW (MHz)
48.3
65.8
49.1
63.6
43.6
42.1
45.8
61.3
45.0
52.1
32.4
42.7
28.7
30.9
27.2
32.1
22.1
27.8
LT1204
SMALL SIGNAL
PEAKING (dB)
0.1
0
0.1
0.1
0.1
0.1
0
0.1
0
0
0
0.1
0.1
0.1
0
0.1
0
0.1
TRUTH TABLE
A1 A0 ENABLE SHUTDOWN
00
01
10
11
1
1
1
1
1
1
1
1
XX
0
1
XX
X
0
CHANNEL
SELECTED
VIN0
VIN1
VIN2
VIN3
High Z Output
Off
5
5 Page 
LT1204
APPLICATI S I FOR ATIO
monitors. The reference pin has no effect when the LT1204
is operating on ±5V, and should be grounded. On supply
voltages above ±8V, the range of voltages for Pin 8 should
be between – 6.5V and – 7.5V. Reducing Pin 8 voltage
below – 7.5V turns “on” the “off” tee switch, and the
isolation between channels is lost.
Channel-to-Channel Switching
CMOS MUX
A0 PIN 9
BIPOLAR
MUX
Competitive MUXs
VIN0 AND VIN1 CONNECTED TO 2MHz SINEWAVE
1204 AI06
VOUT PIN 15
VIN0 AND VIN1 CONNECTED TO 2MHz SINEWAVE
PIN 8 VOLTAGE = –6.8V, VS = ±15V
Transient at Input Buffer
1204 AI04
A0 PIN 9
VIN0 PIN 1
SWITCHING BETWEEN VIN0 AND VIN1
RS = 50Ω, VREF = – 6.8V, VS ±15V
1204AI05
Competitive video multiplexers built in CMOS are bidirec-
tional and suffer from poor output-to-input isolation and
cause transients to feed to the inputs. CMOS MUXs have
been built with “break-before-make” switches to eliminate
the talking between channels, but these suffer from output
glitches large enough to interfere with sync circuitry.
Multiplexers built on older bipolar processes that switch
lateral PNP transistors take several microseconds to settle
and blur the transition between pictures.
Crosstalk
The crosstalk, or more accurately all hostile crosstalk, is
measured by driving a signal into any three of the four
inputs and selecting the 4th input with the logic control.
This 4th input is either shorted to ground or terminated in
an impedance. All hostile crosstalk is defined as the ratio
in decibel of the signal at the output of the CFA to the signal
on the three driven inputs, and is input-referred. Disable
crosstalk is measured with all four inputs driven and the
part disabled. Crosstalk is critical in many applications
where video multiplexers are used. In professional video
systems, a crosstalk figure of – 72dB is a desirable
specification.
The key to the outstanding crosstalk performance of the
LT1204 is the use of tee switches (see Figure 1). When the
tee switch is on (Q2 off) Q1 and Q3 are a pair of emitter
followers with excellent AC response for driving the CFA.
V+
VIN0
TO LOGIC
I1
Q1
Q2
V–
Q3
+
CFA
–
FB
I2
–V
RG
VOUT
RF
1204 F01
Figure 1. Tee Switch
11
11 Page | ||
| Páginas | Total 20 Páginas | |
| PDF Descargar | [ Datasheet LT1204.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| LT120 | Hall Voltage 160mV GaAs Hall Device |  Sharp Electrionic Components |
| LT1201 | Op Amps | Linear Technology |
| LT1201-7 | 500 Watt AC-DC Converters |  Power-One |
| LT1202 | Op Amps | Linear Technology |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |