LT1195 - Low Power, High Speed Operational Amplifier · The LT ®1195 is a video operational...
Transcript of LT1195 - Low Power, High Speed Operational Amplifier · The LT ®1195 is a video operational...
1
LT1195
1195fa
FEATURES DESCRIPTIO
U
APPLICATIO SU
TYPICAL APPLICATIO
U
Low Power, High SpeedOperational Amplifier
Gain-Bandwidth Product: 50MHz Unity-Gain Stable Slew Rate: 165V/µs Output Current: ±20mA Low Supply Current: 12mA High Open-Loop Gain: 7.5V/mV Low Cost Single Supply 5V Operation Industry Standard Pinout Output Shutdown
Video Cable Drivers Video Signal Processing Fast Peak Detectors Fast Integrators Video Cable Drivers Pulse Amplifiers
The LT®1195 is a video operational amplifier optimized foroperation on single 5V and ±5V supplies. Unlike manyhigh speed amplifiers, the LT1195 features high open-loop gain, over 75dB, and the ability to drive heavy loadsto a full power bandwidth of 8.5 MHz at 6VP-P. The LT1195has a unity-gain stable bandwidth of 50MHz, a 60° phasemargin and consumes only 12mA of supply current,making it extremely easy to use.
Because the LT1195 is a true operational amplifier, it is anideal choice for wideband signal conditioning, fastintegrators, peak detectors, active filters, and applicationsrequiring speed, accuracy, and low cost.
The LT1195 is a low power version of the popular LT1190,and is available in 8-pin miniDIPs and SO packages withstandard pinouts. The normally unused Pin 5 is used for ashutdown feature that shuts off the output and reducespower dissipation to a mere 15mW.
Fast Pulse Detector Pulse Detector Response
–
+LT1195RS
50ΩVIN
D21N5712
D11N5712
RL10k
–5V
–5V
RB10k
–5V
5V
CL1000pF
CI60pF
RI1k
1195 TA01
3
24
7
6
1195TAO2
OUTPUT
INPUT
, LTC and LT are registered trademarks of Linear Technology Corporation
www.BDTIC.com/Linear
2
LT1195
1195fa
LT1195M/CSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITSVOS Input Offset Voltage J8, N8 Package 3.0 8.0 mV
S8 Package 3.0 10.0 mVIOS Input Offset Current 0.2 1.0 µAIB Input Bias Current ±0.5 ±2.0 µAen Input Noise Voltage fO = 10kHz 70 nV√Hzin Input Noise Current fO = 10kHz 2 pA√HzRIN Input Resistance Differential Mode 230 kΩ
Common Mode 20 MΩ
CIN Input Capacitance AV = 1 2.2 pFInput Voltage Range (Note 4) –2.5 3.5 V
CMRR Common Mode Rejection Ratio VCM = –2.5 to 3.5V 60 85 dBPSRR Power Supply Rejection Ratio VS = ±2.375V to ±8V 60 85 dBAVOL Large-Signal Voltage Gain RL = 1k, VOUT = ±3V 2.0 7.5 V/mV
RL = 150Ω, VOUT = ±3V 0.5 1.5 V/mVVS = ±8V, RL = 1k, VOUT = ±5V 11.0 V/mV
VOUT Output Voltage Swing VS = ±5V, RL = 1k ±3.8 ±4.0 VVS = ±8V, RL = 1k ±6.7 ±7.0 V
SR Slew Rate AV = –1, RL = 1k (Note 5, 10) 110 165 V/µsFPBW Full Power Bandwidth VOUT = 6VP-P (Note 6) 8.75 MHzGBW Gain-Bandwidth Product 50 MHztr1, tf1 Rise Time, Fall Time AV = 50, VOUT = ±1.5V, 20% to 80% (Note 10) 125 170 285 nstr2, tf2 Rise Time, Fall Time AV = 1, VOUT = ±125mV, 10% to 90% 3.4 nstPD Propagation Delay AV = 1, VOUT = ±125mV, 50% to 50% 2.5 ns
Overshoot AV = 1, VOUT = ±125mV 22 %tS Settling Time 3V Step, 0.1% (Note 7) 220 nsDiff AV Differential Gain RL = 150Ω, AV = 2 (Note 8) 1.25 %Diff Ph Differential Phase RL = 150Ω, AV = 2 (Note 8) 0.86 DEGP-P
S8 PART MARKING
Total Supply Voltage (V+ to V–) ............................... 18VDifferential Input Voltage ......................................... ±6VInput Voltage ........................................................... ±VSOutput Short-Circuit Duration (Note 2) .........ContinuousOperating Temperature Range LT1195M (OBSOLETE) ................... –55°C to 125°C LT1195C ................................................ 0°C to 70°CJunction Temperature (Note 3)
Plastic Package (CN8, CS8) ............................ 150°CCeramic Package (CJ8, MJ8) (OBSOLETE) ..... 175°C
Storage Temperature Range ................. –65°C to 150°CLead Temperature (Soldering, 10 sec).................. 300°C
ORDER PARTNUMBER1
2
3
4
8
7
6
5
TOP VIEW
BAL
–IN
+IN
V–
BAL
V+
OUT
S/D
S8 PACKAGE8-LEAD PLASTIC SO
J8 PACKAGE8-LEAD CERDIP
N8 PACKAGE8-LEAD PDIP
TJMAX = 150°C, θJA = 100°C/ W (J8)
VS = ±5V, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
LT1195CN8LT1195CS8
TJMAX = 150°C, θJA = 100°C/ W (N8)TJMAX = 150°C, θJA = 150°C/ W (S8)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
OBSOLETE PACKAGEConsider the N8 or S8 Package for Alternate Source
LT1195MJ8LT1195CJ8
1195ORDER PART
NUMBER
(Note 1)
TA = 25°C
ABSOLUTE AXI U RATI GS
W WW U
PACKAGE/ORDER I FOR ATIOU UW
5V ELECTRICAL CHARACTERISTICS+–
www.BDTIC.com/Linear
3
LT1195
1195fa
LT1195M/CSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VOS Input Offset Voltage J8, N8 Package 3.0 9.0 mVS8 Package 3.0 11.0 mV
IOS Input Offset Current 0.2 1.0 µAIB Input Bias Current ±0.5 ±2.0 µA
Input Voltage Range (Note 4) 2.0 3.5 VCMRR Common Mode Rejection Ratio VCM = 2V to 3.5V 60 85 dBAVOL Large-Signal Voltage Gain RL = 150Ω to Ground, VOUT = 1V to 3V 0.5 3.0 V/mVVOUT Output Voltage Swing RL = 150Ω to Ground VOUT High 3.5 3.8 V
VOUT Low 0.25 0.4 VSR Slew Rate AV = –1, VOUT = 1V to 3V 140 V/µsGBW Gain-Bandwidth Product 45 MHzIS Supply Current 11 15 mA
Shutdown Supply Current Pin 5 at V – 0.8 1.5 mAIS/D Shutdown Pin Current Pin 5 at V – 5 25 µA
LT1195M/CSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITSIS Supply Current 12 16 mA
Shutdown Supply Current Pin 5 at V – 0.8 1.5 mAIS/D Shutdown Pin Current Pin 5 at V – 5 25 µAtON Turn-On Time Pin 5 from V– to Ground, RL = 1k 160 nstOFF Turn-Off Time Pin 5 from Ground to V–, RL = 1k 700 ns
VS = ±5V, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
VS+ = 5V, VS
–, = OV, VCM = 2.5V, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
LT1195MSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITSVOS Input Offset Voltage 3.0 15.0 mV∆VOS/∆T Input VOS Drift 17 µV/°CIOS Input Offset Current 0.2 2.0 µAIB Input Bias Current ±0.5 ±2.5 µACMRR Common Mode Rejection Ratio VCM = –2.5V to 3.5V 55 85 dBPSRR Power Supply Rejection Ratio VS = ±2.375V to ±8V 55 80 dBAVOL Large-Signal Voltage Gain RL = 1k, VOUT = ±3V 1.50 5.0 V/mV
RL = 150Ω, VOUT = ±3V 0.25 0.8 V/mVVOUT Output Voltage Swing RL = 1k ±3.7 ±3.9 VIS Supply Current 12 18 mA
Shutdown Supply Current Pin 5 at V –, (Note 9) 0.8 2.5 mAIS/D Shutdown Pin Current Pin 5 at V – 5 25 µA
VS = ±5V, Pin 5 open circuit, unless otherwise noted.
–55°C ≤ TA ≤ 125°C, (Note 11)
TA = 25°C
TA = 25°C
5V ELECTRICAL CHARACTERISTICS+–
5V ELECTRICAL CHARACTERISTICS+–
5V ELECTRICAL CHARACTERISTICS
www.BDTIC.com/Linear
4
LT1195
1195fa
LT1195CSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VOS Input Offset Voltage J8, N8 Package 1.0 10.0 mVS8 Package 1.0 15.0 mV
∆VOS/∆T Input VOS Drift 15 µV/°CIOS Input Offset Current 0.2 1.7 µAIB Input Bias Current ±0.5 ±2.5 µA
Input Voltage Range (Note 4) 2.0 3.5 VCMRR Common Mode Rejection Ratio VCM = 2V to 3.5V 60 85 dBVOUT Output Voltage Swing RL = 150Ω to Ground VOUT High 3.5 3.75 V
VOUT Low 0.15 0.4 VIS Supply Current 12 16 mA
Shutdown Supply Current Pin 5 at V– (Note 9) 0.9 2.0 mAIS/D Shutdown Pin Current Pin 5 at V– 5 25 µA
LT1195CSYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITSVOS Input Offset Voltage J8, N8 Package 3.0 10.0 mV
S8 Package 3.0 15.0 mV∆VOS/∆T Input VOS Drift 12 µV/°CIOS Input Offset Current 0.2 1.7 µAIB Input Bias Current ±0.5 ±2.5 µACMRR Common Mode Rejection Ratio VCM = –2.5V to 3.5V 60 85 dBPSRR Power Supply Rejection Ratio VS = ±2.375V to ±5V 60 90 dBAVOL Large-Signal Voltage Gain RL = 1k, VOUT = ±3V 2.0 7.5 V/mV
RL = 150Ω, VOUT = ±3V 0.3 1.5 V/mVVOUT Output Voltage Swing RL = 1k ±3.7 ±3.9 VIS Supply Current 12 17 mA
Shutdown Supply Current Pin 5 at V – (Note 9) 0.9 2.0 mAIS/D Shutdown Pin Current Pin 5 at V – 5 25 µA
0°C ≤ TA ≤ 70°CVS = ±5V, Pin 5 open circuit, unless otherwise noted.
0°C ≤ TA ≤ 70°CVS
+ = 5V, VS– = OV, Pin 5 open circuit, unless otherwise noted.
Note 1: Absolute Maximum Ratings are those values beyond which the lifeof a device may be impaired.Note 2: A heat sink may be required to keep the junction temperaturebelow absolute maximum when the output is shorted continuously.Note 3: TJ is calculated from the ambient temperature TA and powerdissipation PD according to the following formats:
LT1195MJ8/LT1195CJ8: TJ = TA + (PD • 100°C/W)LT1195N: TJ = TA + (PD • 100°C/W)LT1195CS: TJ = TA + (PD • 150°C/W)
Note 4: Exceeding the input common mode range may cause the outputto invert.Note 5: Slew rate is measured between ±1V on the output, with ±3V inputstep.
Note 6: Full power bandwidth is calculated from the slew ratemeasurement: FPBW = SR/2πVP.Note 7: Settling time measurement techniques are shown in “Take theGuesswork Out of Settling Time Measurements,” EDN, September 19, 1985.Note 8: NTSC (3.58MHz). For RL = 1k, Diff AV = 0.3%, Diff Ph = 0.35°.Note 9: See Applications Information section for shutdown at elevatedtemperatures. Do not operate the shutdown above TJ > 125°C.Note 10: AC parameters are 100% tested on the ceramic and plastic DIPpackaged parts (J8 and N8 suffix) and are sample tested on every lot ofthe SO packaged parts (S8 suffix).Note 11: Do not operate at AV < 2 for TA < 0°C.
5V ELECTRICAL CHARACTERISTICS+–
5V ELECTRICAL CHARACTERISTICS
www.BDTIC.com/Linear
5
LT1195
1195fa
TYPICAL PERFOR A CE CHARACTERISTICS
UW
TEMPERATURE (°C)–50
COM
MON
MOD
E RA
NGE
(V)
V+
–0.5
–1.0
–1.5
–2.0
2.0
1.5
1.0
0.5
V–
0 25 75 125
1195 G03
–25 50 100
V+ = 1.8V TO 9V
V+ = –1.8V TO –9V
Common Mode Voltage vsTemperature
Equivalent Input Noise Voltagevs Frequency
Equivalent Input Noise Currentvs Frequency
Output Voltage Swing vsLoad Resistance
COMMON MODE VOLTAGE (V)–5
INPU
T BI
AS C
URRE
NT (
A)
3.0
2.5
2.0
1.5
1.0
0.5
0
–0.5–2 0 2 4
1195 G01
µ
–4 –1 1 3–3 5
VS = ±5V
–55°C
25°C
125°C
TEMPERATURE (°C)–50
INPU
T BI
AS C
URRE
NT (n
A)
100
0
–100
–200
–300
–4000 25 75 125
1195 G02
–25 50 100
+IB
–IB
IOS
VS = ±5V
Input Bias Current vsTemperature
Input Bias Current vsCommon Mode Voltage
FREQUENCY (Hz)
EQUI
VALE
NT IN
PUT
NOIS
E VO
LTAG
E (n
V/√H
z) 600
500
400
300
200
100
010 1k 10k 100k
1195 G04
100
VS = ±5VTA = 25°CRS = 0Ω
FREQUENCY (Hz)
EQUI
VALE
NT IN
PUT
NOIS
E CU
RREN
T (p
A/√H
z) 14
12
10
8
6
4
210 1k 10k 100k
1195 G05
100
VS = ±5VTA = 25°CRS = 100k
±SUPPLY VOLTAGE (V)0
SUPP
LY C
URRE
NT (m
A)
16
14
12
10
82 4 6 10
1195 G06
8
–55°C
125°C
25°C
Supply Current vs Supply Voltage
Shutdown Supply Currentvs Temperature
LOAD RESISTANCE (Ω)10
OUTP
UT V
OLTA
GE S
WIN
G (V
)
5
3
1
–1
–3
–5100 1k
1195 G08
TA = –55°C
TA = 125°CTA = 25°C
VS = ±5V
TA = 125°C
TA = 25°C
TA = –55°C
TEMPERATURE (°C)–50
OPEN
-LOO
P GA
IN (V
/V)
10k
8k
6k
4k
2k
00 25 75 125
1195 G09
–25 50 100
RL = 1kVS = ±5VVO = ±3V
RL = 150Ω
Open-Loop Gain vs Temperature
TEMPERATURE (°C)–50
SHUT
DOW
N SU
PPLY
CUR
RENT
(mA)
6
5
4
3
2
1
00 25 75 125
1195 G07
–25 50 100
VS = ±5VVS/D = –VEE + 0.6V
VS/D = –VEE + 0.2V
VS/D = –VEE + 0.4V
VS/D = –VEE
www.BDTIC.com/Linear
6
LT1195
1195fa
FREQUENCY (Hz)100k
VOLT
AGE
GAIN
(dB)
1M 10M 100M
1195 G10
100
80
60
40
20
0
–20
PHASE MARGIN (DEG)
100
80
60
40
20
0
–20
VS = ±5VTA = 25°CRL = 1k
PHASE
GAIN
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Gain-Bandwidth Product vsSupply Voltage
Common Mode Rejection Ratiovs Frequency
Power Supply Rejection Ratiovs Frequency
Gain and Phase vs Frequency
±SUPPLY VOLTAGE (V)0
GAIN
-BAN
DWID
TH P
RODU
CT (M
Hz)
60
50
40
30
202 4 6 10
1195 G12
8
TA = –55°C
TA = 125°C
TA = 25°C
AV = 20dB
Open-Loop Voltage Gain vsLoad Resistance
LOAD RESISTANCE (Ω)100
OPEN
-LOO
P VO
LTAG
E GA
IN (V
/V)
20k
16k
12k
8k
4k
01k 10k
1195 G11
VS = ±5VVO = ±3VTA = 25°C
TEMPERATURE (°C)–50
100
90
80
70
60
50
40
3025 75
1195 G13
–25 0 50 100 125
UNIT
Y-GA
IN F
REQU
ENCY
(MHz
)
90
80
70
60
50
40
30
20
PHASE MARGIN (DEG)
UNITY-GAINFREQUENCY
VS = ±5VRL = 1k
UNITY-GAINPHASE MARGIN
FREQUENCY (Hz)
OUTP
UT IM
PEDA
NCE
(Ω)
100
10
1
0.1
0.011k 100k 10M
1195 G14
10k 1M 100M
VS = ±5VTA = 25°C
AV = 10
AV = 1
FREQUENCY (Hz)100k
COM
MON
MOD
E RE
JECT
ION
RATI
O (d
B)
1M 10M 100M
1195 G15
60
50
40
30
20
10
0
VS = ±5VTA = 25°CRL = 1k
FREQUENCY (Hz)
POW
ER S
UPPL
Y RE
JECT
ION
RATI
O (d
B)
80
60
40
20
0
–20100M10k 100k 10M
1195 G16
1k 1M
VS = ±5VTA = 25°CVRIPPLE = ±300mV
+PSRR–PSRR
TEMPERATURE (°C)–50
OUTP
UT S
HORT
-CIR
CUIT
CUR
RENT
(mA)
36
35
34
33
32
31
300 25 75 125
1195 G17
–25 50 100
VS = ±5V
Unity-Gain Frequency and PhaseMargin vs Temperature Output Impedance vs Frequency
Output Short-Circuit Currentvs Temperature
SUPPLY VOLTAGE (V)0
OUTP
UT S
ATUR
ATIO
N VO
LTAG
E (V
)
–0.7
–0.8
–0.9
–1.0
–1.1
0.5
0.4
0.3
0.2
0.1V– 2 4 10
1195 G18
6 8
V+
25°C
125°C
–55°C
25°C
125°C
–55°C
RL = RFB±1.8V ≤ VS ≤ ±9V
±Output Swing vs Supply Voltage
www.BDTIC.com/Linear
7
LT1195
1195fa
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Output Voltage Step vsSettling Time, AV = –1
Output Voltage Step vsSettling Time, AV = 1
TEMPERATURE (°C)–50
SLEW
RAT
E (V
/µs)
250
200
1500 25 75 125
1195 G19
–25 50 100
+SLEW RATE
–SLEW RATE
VS = ±5VRFB = 1kVO = ±2VAV = –1
SETTLING TIME (ns)0
OUTP
UT V
OLTA
GE S
TEP
(V)
400
1195 G20
100 200 300
4
2
0
–2
–4
VS = ±5VTA = 25°CRL = 1k
10mV
10mV
1mV
1mV
SETTLING TIME (ns)0
OUTP
UT V
OLTA
GE S
TEP
(V)
400
1195 G21
100 200 300
4
2
0
–2
–4
VS = ±5VTA = 25°CRL = 1k
10mV
10mV
1mV
1mV
Slew Rate vs Temperature
1195 G25
–
+LT1195
3
28
1
4
7
6
INPUT OFFSET VOLTAGE CAN BE ADJUSTED OVER A±150mV RANGE WITH A 1k to 10k POTENTIOMETER.
5V
Large-Signal Transient Response
AV = –1, RL = 1k
Large-Signal Transient Response
AV = 1, RL = 1k
Overload Recovery
1195 G22
AV = 1, VIN = 11VP-P1195 G24
1195 G23
www.BDTIC.com/Linear
8
LT1195
1195fa
receiving end (75Ω to ground) to absorb unwanted en-ergy. The best performance can be obtained by doubletermination (75Ω in series with the output of the amplifier,and 75Ω to ground at the other end of the cable). Thistermination is preferred because reflected energy is ab-sorbed at each end of the cable. When using the doubletermination technique it is important to note that the signalis attenuated by a factor of 2, or 6dB. This can be compen-sated for by taking a gain of 2, or 6dB in the amplifier.
Using the Shutdown Feature
The LT1195 has a unique feature that allows the amplifierto be shut down for conserving power, or for multiplexingseveral amplifiers onto a common cable. The amplifier willshutdown by taking Pin 5 to V –. In shutdown, the amplifierdissipates 15mW while maintaining a true high impedanceoutput state of 15k in parallel with the feedback resistors.The amplifiers must be used in a noninverting configura-tion for MUX applications. In inverting configurations theinput signal is fed to the output through the feedbackcomponents. The following scope photos show that withvery high RL, the output is truly high impedance; theoutput slowly decays toward ground. Additionally, whenthe output is loaded with as little as 1k the amplifier shutsoff in 700ns. This shutoff can be under the control of HCCMOS operating between 0V and –5V.
APPLICATIO S I FOR ATIO
WU UU
Power Supply Bypassing
The LT1195 is quite tolerant of power supply bypassing.In some applications a 0.1µF ceramic disc capacitorplaced 0.5 inches from the ampifier is all that is required.In applications requiring good settling time, it is importantto use multiple bypass capacitors. A 0.1µF ceramic disc inparallel with a 4.7µF tantalum is recommended.
Cable Terminations
The LT1195 operational amplifier has been optimized as alow cost video cable driver. The ±20mA guaranteed outputcurrent enables the LT1195 to easily deliver 6VP-P into150Ω, while operating on ±5V supplies.
–
+LT1195
75ΩRFB
–5V
5V
CABLE
1195 AI01
3
2
7
4
6 75Ω
RG
FREQUENCY (Hz)100k
VOLT
AGE
GAIN
(dB)
1M 10M 100M
1195 AI02
8
6
4
2
0
–2
–4
–6
–8
–10
–12
AV = 2RFB = 1kRG = 330Ω
AV = 1RFB = 1kRG = 1k
VS = ±5VTA = 25°C
Cable Driver Voltage Gain vs Frequency
Double-Terminated Cable Driver
Output Shutdown
1MHz SINE WAVE GATED OFF WITH SHUTDOWN PIN
AV = 1, RL = SCOPE PROBE
When driving a cable it is important to terminate the cableto avoid unwanted reflections. This can be done in one oftwo ways: single termination or double termination. Withsingle termination, the cable must be terminated at the
1195 AI03
www.BDTIC.com/Linear
9
LT1195
1195fa
APPLICATIO S I FOR ATIO
WU UU
Output Shutdown
–
+LT1195
75ΩRFB1k
5V
1195 AI05
3
2
7
4
6 75Ω1000µF
10k
10µF
1k
5V
RG1k
VIN
R22k
100µF
R13k
Video Multiburst at Pin 6 of Amplifier
Detecting Pulses
The front page shows a circuit for detecting very fastpulses. In this open-loop design, the detector diode is D1and a level shifting or compensating diode is D2. A loadresistor RL is connected to –5V, and an identical biasresistor RB is used to bias the compensating diode. Equalvalue resistors ensure that the diode drops are equal. Avery fast pulse will exceed the amplifier slew rate andcause a long overload recovery time. Some amount ofdV/dt limiting on the input can help this overload condi-tion, however too much will delay the response. Alsoshown is the response to a 4VP-P input that is 150ns wide.The maximum output slew rate in the photo is 30V/µs. Thisrate is set by the 30mA current limit driving 1000pF.
Operation on Single 5V Supply
The LT1195 has been optimized for a single 5V supply.This circuit amplifies standard composite video (1VP-Pincluding sync) by 2 and drives a double-terminated 75Ωcable. Resistors R1 and R2 bias the amplifier at 2V,allowing the sync pulses to stay within the common moderange of the amplifier. Large coupling capacitors arerequired to pass the low frequency sidebands of thecomposite signal. A multiburst response and vector plotstandard color burst are shown.
Single 5V Video Amplifier
1195 AI04
1MHz SINE WAVE GATED OFF WITH SHUTDOWN PIN
AV = 1, RL = 1k
Vector Plot of Standard Color Burst
1195 AI06
3V
2V
1V
0V
1195 AI07
www.BDTIC.com/Linear
10
LT1195
1195fa
APPLICATIO S I FOR ATIO
WU UU
Send Color Video Over Twisted-Pair
With an LT1195 it is possible to send and receive colorcomposite video signals more than 1000 feet on a low costtwisted-pair. A bidirectional “video bus” consists of theLT1195 op amp and the LT1187 video difference amplifier.A pair of LT1195s at TRANSMIT 1, is used to generatedifferential signals to drive the line which is back-termi-nated in its characteristic impedance. The LT1187twisted-pair receiver, converts signals from differential tosingle-ended. Topology of the LT1187 provides for cablecompensation at the amplifier’s feedback node as shown.In this case, 1000 feet of twisted-pair is compensated with1000pF and 50Ω to boost the 3dB bandwidth of thesystem from 750kHz to 4MHz. This bandwidth is adequateto pass a 3.58MHz chrome subcarrier and the 4.5MHzsound subcarrier. Attenuation in the cable can be compen-sated by lowering the gain set resistor RG. At TRANSMIT2, another pair of LT1195s serve the dual function toprovide cable termination via low output impedance andgenerate differential signals for TRANSMIT 2. Cable termi-nation is made up of 15Ω and 33Ω attentuators to reducethe differential input signal to the LT1187. Maximum inputsignal for the LT1187 is 760mVP-P.
1.5MHz Square Wave Input and EqualizedResponse Through 1000 Feet of Twisted-Pair
1.5MHz Square Wave Input and UnequalizedResponse Through 1000 Feet of Twisted-Pair
Multiburst Pattern Passed Through1000 Feet of Twisted-Pair
Vector Plot of Standard Color Burst Through1000 Feet of Twisted-Pair
1195 A109
1195 A110
1195 A111
1195 A108
www.BDTIC.com/Linear
11
LT1195
1195fa
+
–VOUT
1195 SS
VBIAS
CM
CFF
V+V+
3
2
1 85BAL BALS/D
6
*
V+7
V–4
* SUBSTRATE DIODE, DO NOT FORWARD BIAS
VBIAS
APPLICATIO S I FOR ATIO
WU UU
Bidirectional Video Bus
1195 AI12
–
+LT1195
75Ω
33Ω
3
2
6
1k
1k
1k
1k
1000pF
–
+
–
+
+–
S/D
5
6LT1187
15Ω
RFB300Ω
RG300Ω
75Ω
50Ω
2
3
6
33Ω
15Ω
LT1195
RECEIVE 2
33Ω
3
2
6
1k
1k1k
1k
1000pF
S/D
5
6
15Ω
RFB300Ω
RG300Ω
75Ω
50Ω
2
3
6
33Ω
15Ω
–
+
75Ω
–
+
–
+
+–
RECEIVE 1
3
2
1
8
3
2
1
8
TRANSMIT 1 TRANSMIT 2
LT1195
LT1195
LT1187
1000 FTTWISTED-PAIR
SIWPLIFIED SCHEWATIC
W W
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.www.BDTIC.com/Linear
12
LT1195
1195fa
Linear Technology Corporation1630 McCarthy Blvd., Milpitas, CA 95035-7417(408) 432-1900 FAX: (408) 434-0507 www.linear.com
LW/TP 1002 1K REV A • PRINTED IN USA
LINEAR TECHNOLOGY CORPORATION 1993
U
PACKAGE DESCRIPTIO
.016 – .050(0.406 – 1.270)
.010 – .020(0.254 – 0.508)
× 45°
0°– 8° TYP.008 – .010
(0.203 – 0.254)
SO8 0502
.053 – .069(1.346 – 1.752)
.014 – .019(0.355 – 0.483)
TYP
.004 – .010(0.101 – 0.254)
.050(1.270)
BSC
1
N
2 3 4
N/2
.150 – .157(3.810 – 3.988)
NOTE 3
8 7 6 5
.189 – .197(4.801 – 5.004)
NOTE 3
.228 – .244(5.791 – 6.197)
.245MIN
N
1 2 3 N/2
.160 ±.005
RECOMMENDED SOLDER PAD LAYOUT
.045 ±.005 .050 BSC
.030 ±.005 TYP
INCHES(MILLIMETERS)
NOTE:1. DIMENSIONS IN
2. DRAWING NOT TO SCALE3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
S8 Package8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
N8 0502
.100(2.54)BSC
.065(1.651)
TYP
.045 – .065(1.143 – 1.651)
.130 ± .005(3.302 ± 0.127)
.020(0.508)
MIN.018 ± .003(0.457 ± 0.076)
.125(3.175)
MIN
1 2 3 4
8 7 6 5
.255 ± .015*(6.477 ± 0.381)
.400*(10.160)
MAX
.009 – .015(0.229 – 0.381)
.300 – .325(7.620 – 8.255)
.325+.035–.015+0.889–0.3818.255( )
NOTE:1. DIMENSIONS ARE
INCHESMILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
N8 Package8-Lead PDIP (Narrow .300 Inch)(Reference LTC DWG # 05-08-1510)
J8 0801
.014 – .026(0.360 – 0.660)
.015 – .060(0.381 – 1.524)
.1253.175MIN
.100(2.54)BSC
.300 BSC(7.62 BSC)
.008 – .018(0.203 – 0.457)
0° – 15°
.045 – .065(1.143 – 1.651)
.045 – .068(1.143 – 1.650)
FULL LEADOPTION
.023 – .045(0.584 – 1.143)
HALF LEADOPTION
CORNER LEADS OPTION (4 PLCS)
.200(5.080)
MAX
.005(0.127)
MIN
.405(10.287)
MAX
.220 – .310(5.588 – 7.874)
1 2 3 4
8 7 6 5
.025(0.635)
RAD TYP
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS
J8 Package8-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
OBSOLETE PACKAGE
www.BDTIC.com/Linear