LT1193
Video Difference
Amplifier
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FEATURES
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DESCRIPTIO
The LT®1193 is a video difference amplifier optimized for
operation on ±5V and a single 5V supply. This versatile
amplifier features uncommitted high input impedance (+)
and (–) inputs, and can be used in differential or singleended configurations. Additionally, a second set of inputs
give gain adjustment and DC control to the differential
amplifier.
Differential or Single-Ended Gain Block (Adjustable)
–3dB Bandwidth, AV = ±2: 80MHz
Slew Rate: 500V/µs
Low Cost
Output Current: ±50mA
Settling Time: 180ns to 0.1%
CMRR at 10MHz: > 40dB
Differential Gain Error: 0.2%
Differential Phase Error: 0.08°
Single 5V Operation
Drives Cables Directly
Output Shutdown
The LT1193’s high slew rate, 500V/µs, wide bandwidth,
80MHz, and ±50mA output current make it ideal for
driving cables directly. The shutdown feature reduces the
power dissipation to a mere 15mW and allows multiple
amplifiers to drive the same cable.
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APPLICATIO S
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, LTC and LT are registered trademarks of Linear Technology Corporation.
Line Receivers
Video Signal Processing
Cable Drivers
Oscillators
Tape and Disc Drive Systems
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The LT1193 is available in 8-pin PDIP and SO packages.
TYPICAL APPLICATIO
Cable Sense Amplifier for Loop Through Connections with DC Adjust
VIN
5V
3
CABLE
2
VDC
1
8
+
–
+
–
7
LT1193
6
75Ω
VOUT
75Ω
4
–5V
300Ω
LT1193 • TA01
300Ω
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LT1193
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ABSOLUTE
RATI GS
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PACKAGE/ORDER I FOR ATIO
(Note 1)
Total Supply Voltage (V + to V –) .............................. 18V
Differential Input Voltage ........................................ ± 6V
Input Voltage .......................................................... ± VS
Output Short-Circuit Duration (Note 2) ......... Continuous
Operating Temperature Range
LT1193M (OBSOLETE) ................ – 55°C to 125°C
LT1193C .................................................. 0°C to 70°C
LT1193I ...............................................–40°C to 85°C
Maximum Temperature ........................................ 150°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
TOP VIEW
+/REF 1
8
–/FB
–IN 2
7
V+
+IN 3
6
OUT
V– 4
5
SHDN
N8 PACKAGE
8-LEAD PDIP
S8 PACKAGE
8-LEAD PLASTIC SO
LT1193CN8
LT1193CS8
LT1193IS8
S8 PART MARKING
TJMAX = 150°C, θJA = 100°C/W (N8)
TJMAX = 150°C, θJA = 150°C/W (S8)
1193
1193I
J8 PACKAGE 8-LEAD CERDIP
TJMAX = 150°C, θJA = 100°C/W
LT1193MJ8
LT1193CJ8
OBSOLETE PACKAGE
Consider the N8 or S8 Packages for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
VS = ±5V, VREF = 0V, RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8
to ground, RL = RFB1 + RFB2 = 1k (Note 3), TA = 25°C, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
SYMBOL
VOS
IOS
IB
en
in
RIN
CIN
VIN(LIM)
CMRR
PSRR
VOUT
PARAMETER
Input Offset Voltage
Input Offset Current
Input Bias Current
Input Noise Voltage
Input Noise Current
Input Resistance
Input Capacitance
Input Voltage Limit
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
GE
Gain Error
SR
FPBW
BW
tr, t f
tPD
Slew Rate
Full-Power Bandwidth
Small-Signal Bandwidth
Rise Time, Fall Time
Propagation Delay
Overshoot
Settling Time
Differential Gain
Differential Phase
ts
Diff AV
Diff Ph
CONDITIONS
Both Inputs (Note 4) All Packages
Either Input
Either Input
fO = 10kHz
fO = 10kHz
Either Input
Either Input
(Note 5)
VCM = – 2.5V to 3.5V
VS = ±2.375V to ±8V
VS = ±5V, RL = 1k
VS = ±8V, RL = 1k
VS = ±8V, RL = 100Ω
VO = ±3V, RL = 1k
RL = 100Ω
VO = ±2V, RL = 300Ω (Notes 6, 11)
VO = 6VP-P (Note 7)
AV = 50, VO = ±1.5V, 20% to 80% (Note 11)
RL= 1k, VO = ±125mV, 50% to 50%
VO = ±50mV
3V Step, 0.1% (Note 8)
RL = 150Ω, AV = 2 (Note 9)
RL = 150Ω, AV = 2 (Note 9)
MIN
– 2.5
60
60
±3.8
±6.8
6.4
350
18.5
110
LT1193M/C/I
TYP
MAX
2
12
0.2
3
±0.5
±3.5
50
4
100
2
1.3
3.5
75
75
±4
±7
6.6
0.1
1.0
0.1
1.2
500
26.5
9
160
210
15
0
180
0.2
0.08
UNITS
mV
µA
µA
nV/√Hz
pA/√Hz
kΩ
pF
V
V
dB
dB
V
V
V
%
%
V/µs
MHz
MHz
ns
ns
%
ns
%
DegP-P
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LT1193
ELECTRICAL CHARACTERISTICS
VS = ±5V, VREF = 0V, RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8
to ground, RL = RFB1 + RFB2 = 1k (Note 3), TA = 25°C, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
SYMBOL
PARAMETER
IS
Supply Current
CONDITIONS
MIN
LT1193M/C/I
TYP
MAX
35
UNITS
43
mA
1.3
2
mA
20
50
µA
Shutdown Supply Current
Pin 5 at
V–
Shutdown Pin Current
Pin 5 at V –
tON
Turn On Time
300
ns
tOFF
Turn Off Time
Pin 5 from V – to Ground, RL = 1k
Pin 5 from Ground to V –, RL = 1k
200
ns
ISHDN
VS+ = 5V, VS – = 0V, VREF = 2.5V, RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8 to VREF, RL = RFB1 + RFB2 = 1k (Note 3),
TA = 25°C, CL ≤ 10pF, Pin 5 open circuit, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
VOS
Input Offset Voltage
Both Inputs (Note 4) All Packages
IOS
Input Offset Current
Either Input
IB
Input Bias Current
Either Input
3
Input Voltage Range
Common Mode Rejection Ratio
VCM = 2V to 3.5V
VOUT
Output Voltage Swing
RL = 100Ω to Ground
VOUT High
Slew Rate
Small-Signal Bandwidth
IS
Supply Current
ISHDN
mV
0.2
3
µA
±0.5
±3.5
µA
3.5
V
55
70
dB
3.6
3.8
V
VOUT Low
BW
0.25
VO = 1V to 3V
Shutdown Supply Current
Pin 5 at
Shutdown Pin Current
Pin 5 at V –
0.4
V
250
V/µs
8
MHz
32
V–
UNITS
15
2
CMRR
SR
LT1193M/C/I
TYP
MAX
40
mA
1.3
2
mA
20
50
µA
The ● denotes the specificatons which apply over the full operating temperature range of – 55°C ≤ TA ≤ 125°C. VS = ±5V,
VREF = 0V, RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8 to ground, RL = RFB2 = 1k (Note 3), CL ≤ 10pF, Pin 5 open circuit,
unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
LT1193M
TYP
MAX
16
UNITS
VOS
Input Offset Voltage
●
2
∆VOS /∆T
Input VOS Drift
●
20
IOS
Input Offset Current
●
0.8
5
µA
IB
Input Bias Current
●
±1
±5.5
µA
Input Voltage Range
●
–2.5
3.5
V
VCM = – 2.5V to 3.5V
●
53
70
dB
CMRR
Common Mode Rejection Ratio
mV
µV/°C
PSRR
Power Supply Rejection Ratio
VS = ± 2.375V to ± 5V
●
53
70
dB
VOUT
Output Voltage Swing
RL = 1k
●
3.6
4
V
VS = ±8V, RL = 100Ω
●
6
6.5
VO = ± 3V, RL = 1k
●
0.2
1.2
%
●
35
43
mA
●
1.3
2.2
mA
●
20
GE
Gain Error
IS
Supply Current
Shutdown Supply Current
ISHDN
Shutdown Pin Current
Pin 5 at V – (Note 10)
Pin 5 at
V–
µA
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LT1193
ELECTRICAL CHARACTERISTICS
The ● denotes the specificatons which apply over the full operating temperature range of – 40°C ≤ TA ≤ 85°C. VS = ±5V,
VREF = 0V, RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8 to ground, RL = RFB2 = 1k (Note 3), CL ≤ 10pF, Pin 5 open circuit,
unless otherwise noted.
SYMBOL
VOS
∆VOS /∆T
IOS
IB
CMRR
PSRR
VOUT
GE
IS
ISHDN
PARAMETER
Input Offset Voltage
Input VOS Drift
Input Offset Current
Input Bias Current
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
Gain Error
Supply Current
Shutdown Supply Current
Shutdown Pin Current
CONDITIONS
SO-8 Package
MIN
●
●
●
●
●
VCM = – 2.5V to 3.5V
VS = ± 2.375V to ± 5V
RL = 1k
VS = ±8V, RL = 100Ω
VO = ± 3V, RL = 1k
●
●
●
●
–2.5
53
53
3.6
6
●
●
Pin 5 at V – (Note 10)
Pin 5 at V –
●
●
LT1193I
TYP
2
20
0.8
±1
70
70
4
6.5
0.2
35
1.3
20
MAX
20
5
±5.5
3.5
1.2
43
2.2
UNITS
mV
µV/°C
µA
µA
V
dB
dB
V
%
mA
mA
µA
The ● denotes the specificatons which apply over the full operating temperature range of 0°C ≤ TA ≤ 70°C. VS = ±5V, VREF = 0V,
RFB1 = 900Ω from Pins 6 to 8, RFB2 = 100Ω from Pin 8 to ground, RL = RFB1 + RFB2 = 1k (Note 3), CL ≤ 10pF, Pin 5 open circuit,
unless otherwise noted.
SYMBOL
VOS
PARAMETER
Input Offset Voltage
∆VOS /∆T
IOS
IB
Input VOS Drift
Input Offset Current
Input Bias Current
Input Voltage Range
Common Mode Rejection Ratio
Power Supply Rejection Ratio
Output Voltage Swing
CMRR
PSRR
VOUT
GE
IS
ISHDN
Gain Error
Supply Current
Shutdown Supply Current
Shutdown Pin Current
CONDITIONS
N8 Package
SO-8 Package
MIN
●
●
20
0.2
±0.5
●
●
●
●
VCM = – 2.5V to 3.5V
VS = ± 2.375V to ± 5V
RL = 1k
RL = 100Ω
VO = ± 3V, RL = 1k
●
●
●
●
●
●
Pin 5 at V – (Note 10)
Pin 5 at V –
Note 1: Absolute Maximum Ratings are those values beyond which the
life of a device may be impaired.
Note 2: A heat sink is required to keep the junction temperature below
absolute maximum when the output is shorted.
Note 3: When RL = 1k is specified, the load resistor is RFB1 + RFB2, but
when RL = 100Ω is specified, then an additional 100Ω is added to the
output.
Note 4: VOS measured at the output (Pin 6) is the contribution from both
input pair, and is input referred.
Note 5: VIN LIM is the maximum voltage between –VIN and +VIN (Pin 2 and
Pin 3) for which the output can respond.
Note 6: Slew rate is measured between ± 2V on the output, with a ± 1V
input step, AV = 3.
●
●
LT1193C
TYP
2
–2.5
55
55
3.7
6.2
70
70
4
6.6
0.2
35
1.3
20
MAX
14
20
3.5
±4
3.5
1.2
43
2.1
UNITS
mV
mV
µV/°C
µA
µA
V
dB
dB
V
V
%
mA
mA
µA
Note 7: Full-power bandwidth is calculated from the slew rate
measurement:
FPBW = SR/2πVP.
Note 8: Settling time measurement techniques are shown in “Take the
Guesswork Out of Settling Time Measurements,” EDN, September 19,
1985.
Note 9: NTSC (3.58MHz).
Note 10: See Applications section for shutdown at elevated temperatures.
Do not operate the shutdown above TJ > 125°C.
Note 11: AC parameters are 100% tested on the ceramic and plastic DIP
packaged parts (J and N suffix) and are sample tested on every lot of the
SO packaged parts (S suffix).
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LT1193
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TYPICAL PERFOR A CE CHARACTERISTICS
Input Bias Current
vs Common Mode Voltage
–0.3
VS = ±5V
INPUT BIAS CURRENT (µA)
INPUT BIAS CURRENT (µA)
3
2
1
25°C
0
Common Mode Voltage
vs Supply Voltage
–55°C
125°C
–1
10
VS = ±5V
–0.4
+IB
–0.5
IOS
–0.6
–IB
–0.7
–55°C
25°C
8
COMMON MODE VOLTAGE (V)
4
Input Bias Current
vs Temperature
6
+V COMMON MODE
125°C
4
2
0
–2
–55°C
25°C
125°C
–4
–V COMMON MODE
–6
–8
–0.8
–50
–2
–4
–3
1
3
–2 –1
0
2
COMMON MODE VOLTAGE (V)
4
–10
–25
50
0
25
75
TEMPERATURE (°C)
100
LT1193 • TPC01
200
150
100
50
0
100
10
1k
10k
FREQUENCY (Hz)
VS = ±5V
TA = 25°C
RS = 100k
60
40
20
0
10
100k
–55°C
30
125°C
20
100
1k
10k
FREQUENCY (Hz)
0
100k
VS = ±5V
VS = ±5V
2.0
0
OPEN-LOOP GAIN (V/V)
2.5
GAIN ERROR (%)
VSHDN = –VEE + 0.2V
1
RL = 100Ω
RL = 1k
VS = ±5V
VO = ±3V
15k
10k
5k
RL = 100Ω
1.5
–25
0
25
75
50
TEMPERATURE (°C)
RL = 1k
–1
VSHDN = –VEE
1.0
–50
10
Open-Loop Gain vs Temperature
20k
2
VSHDN = –VEE + 0.4V
3.0
4
6
8
±SUPPLY VOLTAGE (V)
LT1193 • TPC06
Gain Error vs Temperature
3
3.5
2
0
4.5
4.0
25°C
LT1193 • TPC05
Shutdown Supply Current
vs Temperature
SHUTDOWN SUPPLY CURRENT (mA)
40
10
LT1193 • TPC04
5.0
Supply Current vs Supply Voltage
50
SUPPLY CURRENT (mA)
250
EQUIVALENT INPUT NOISE CURRENT (pA/√Hz)
EQUIVALENT INPUT NOISE VOLTAGE (nV/√Hz)
300
80
10
LT1193 • TPC03
Equivalent Input Noise Current
vs Frequency
VS = ±5V
TA = 25°C
RS = 0Ω
350
6
4
8
±V SUPPLY VOLTAGE (V)
LT1193 • TPC02
Equivalent Input Noise Voltage
vs Frequency
400
2
0
125
100
125
LT1193 • TPC07
–2
–50 –25
25
0
50
75
TEMPERATURE (°C)
100
125
LT1193 • TPC08
0
–50 –25
25
75
0
50
TEMPERATURE (°C)
100
125
LT1193 • TPC09
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LT1193
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TYPICAL PERFOR A CE CHARACTERISTICS
Open-Loop Voltage Gain
vs Load Resistance
80
60
60
40
40
GAIN
20
20
0 VS = ±5V
TA = 25°C
RL = 1k
–20
100k
0
15k
10k
5k
–20
100M
1M
10M
FREQUENCY (Hz)
80
VS = ±5V
VO = ±3V
TA = 25°C
100
LOAD RESISTANCE (Ω)
10
LT1193 • TPC11
60
65
60
GAIN BANDWIDTH PRODUCT
55
55
50
50
UNITY GAIN
PHASE MARGIN
45
45
40
40
35
35
30
–50 –25
25
75
0
50
TEMPERATURE (°C)
100
100
70
30
125
AV = 10
1
AV = 2
0.1
0.01
0.001
1k
10k
100k
1M
FREQUENCY (Hz)
10M
20
0
–20
1k
10k
1M
100k
FREQUENCY (Hz)
10M
60
50
40
30
100k
100M
100M
LT1193 • TPC16
1M
10M
FREQUENCY (Hz)
100M
LT1193 • TPC15
Output Swing vs Supply Voltage
10
VS = ± 5V
RL = 1k
8
+VOUT, 25°C,
125°C, –55°C
6
OUTPUT SWING (V)
+PSRR
–PSRR
40
100
OUTPUT SHORT-CIRCUIT CURRENT (mA)
POWER SUPPLY REJECTION RATIO (dB)
60
70
Output Short-Circuit Current
vs Temperature
VS = ±5V
TA = 25 °C
VRIPPLE = ±300mV
VS = ±5V
TA = 25°C
RL = 1k
LT1193 • TPC14
Power Supply Rejection Ratio
vs Frequency
10
LT1193 • TPC12
80
VS = ±5V
TA = 25°C
LT1193 • TPC13
80
6
4
8
±SUPPLY VOLTAGE (V)
Common Mode Rejection Ratio
vs Frequency
10
OUTPUT IMPEDANCE (Ω )
65
2
0
1000
Output Impedance vs Frequency
PHASE MARGIN (DEGREES)
GAIN BANDWIDTH PRODUCT (MHz)
VS = ±5V
RL = 1k
TA = –55°C, 25°C, 125°C
60
LT1193 • TPC10
Gain Bandwidth Product and Unity
Gain Phase Margin vs Temperature
70
70
50
0
COMMON MODE REJECTION RATIO (dB)
PHASE
PHASE MARGIN (DEGREES)
80
VOLTAGE GAIN (dB)
20k
100
OPEN-LOOP VOLTAGE GAIN (V/V)
100
Gain Bandwidth Product
vs Supply Voltage
GAIN BANDWIDTH PRODUCT (MHz)
Gain, Phase vs Frequency
90
80
4
2
0
–2
–VOUT, –55°C,
25°C, 125°C
–4
–6
–8
70
–50
–10
–25
50
0
25
75
TEMPERATURE (°C)
100
125
LT1193 • TPC17
0
2
8
4
6
±V SUPPLY VOLTAGE (V)
10
LT1193 • TPC18
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LT1193
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TYPICAL PERFOR A CE CHARACTERISTICS
Output Voltage Step
vs Settling Time, AV = 2
Slew Rate vs Temperature
VS = ± 5V
900
3
TA = –55°C
800
4
OUTPUT VOLTAGE STEP (V)
5
– SLEW RATE
SLEW RATE (V/µs)
OUTPUT VOLTAGE SWING (V)
Output Voltage Swing
vs Load Resistance
TA = 25°C
1
TA = 125°C
–1
TA = 125°C
–3
TA = –55°C, 25°C
–5
10
100
LOAD RESISTANCE (Ω)
1000
700
600
+SLEW RATE
500
VS = ±5V
400 TA = 25°C
RL = 1k
VO = ±2V
300
–50 –25
0
25
50
75
TEMPERATURE (°C)
LT1193 • TPC19
Large-Signal Transient Response
VS = ±5V
TA = 25°C
RL = 1k
2
10mV
0
–2
10mV
–4
100
125
40
LT1193 • TPC20
Small-Signal Transient Response
60
70
80
SETTLING TIME (ns)
90
100
LT1193 • TPC21
Small-Signal Transient Response
LT1193 • TPC23
LT1193 • TPC22
AV = –10, SMALL-SIGNAL RISE TIME = 43ns
AV = 2, RL = 150Ω, RFB = 300Ω, RG = 300Ω
50
LT1193 • TPC24
AV = 2, RFB = 300Ω, RG = 300Ω,
OVERSHOOT = 25%, RISE TIME = 4.7ns
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APPLICATIO S I FOR ATIO
The LT1193 is a video difference amplifier which has two
uncommitted high input impedance (+) and (–) inputs.
The amplifier has one set of inputs that can be used for
reference and feedback. Additionally, this set of inputs
give gain adjust and DC control to the differential amplifier.
The voltage gain of the LT1193 is set like a conventional
operational amplifier. Feedback is applied to Pin 8 and it is
optimized for gains of 2 or greater. The amplifier can be
operated single-ended by connecting either the (+) or (–)
inputs to +/REF, Pin 1. The voltage gain is set by the
resistors: (RFB + RG)/RG.
The primary usefulness of the LT1193 is in converting
high speed differential signals to a single-ended output.
The amplifier has common mode rejection beyond 50MHz
and a full-power bandwidth of 40MHz at 4VP-P. Like the
single-ended case, the differential voltage gain is set by the
external resistors: (RFB + RG)/RG. The maximum input
differential signal for which the output will respond is
approximately ±1.3V.
Power Supply Bypassing
The LT1193 is quite tolerant of power supply bypassing.
In some applications a 0.1µF ceramic disc capacitor
placed 1/2 inch from the amplifier is all that is required. A
scope photo of the amplifier output with no supply bypassing is used to demonstrate this bypassing tolerance,
RL = 1k.
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LT1193
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APPLICATIO S I FOR ATIO
SHDN
VIN
3
2
5
SHDN
V+
7
+
– LT1193
1
+/REF
8
–/FB 4
6
VIN
VOUT
3
2
5
7
+
– LT1193
1
+/REF
8
–/FB 4
V–
RFB
RG
VIN
3
2
VOUT
VOUT
1V/DIV 0V
0V VOUT
10mV/DIV
R + RG
AV = – FB
RG
RG
SHDN
VINDIFF
6
V–
RFB
R + RG
AV = + FB
RG
5
Settling Time Poor Bypass
V+
SHDN
V+
7
+
– LT1193
1
+/REF
8
–/FB 4
6
VINDIFF
VOUT
VIN
RG
3
2
5
V+
7
+
– LT1193
1
+/REF
8
–/FB 4
V–
RFB
LT1192 • TA05
6
SETTLING TIME TO 10mV, AV = 2
SUPPLY BYPASS CAPACITORS = 0.1µF
VOUT
Settling Time Good Bypass
V–
RFB
R + RG
VO = (VINDIFF + VIN) FB
RG
RG
VO =
(R R+ R ( V
FB
G
G
INDIFF –
( RR ( V
FB
G
IN
LT1193 • TA03
VOUT
1V/DIV 0V
No Supply Bypass Capacitors
0V VOUT
10mV/DIV
LT1192 • TA06
SETTLING TIME TO 10mV, AV = 2
SUPPLY BYPASS CAPACITORS = 0.1µF + 4.7µF TANTALUM
Operating With Low Closed-Loop Gains
LT1192 • TA04
AV = 10, IN DEMO BOARD, RL = 1k
In many applications and those requiring good settling
time it is important to use multiple bypass capacitors. A
0.1µF ceramic disc in parallel with a 4.7µF tantalum is
recommended. Two oscilloscope photos with different
bypass conditions are used to illustrate the settling time
characteristics of the amplifier. Note that although the
output waveform looks acceptable at 1V/DIV, when amplified to 10mV/DIV the settling time to 10mV is 347ns for the
0.1µF bypass; the time drops to 96ns with multiple bypass
capacitors.
The LT1193 has been optimized for closed-loop gains of
2 or greater; the frequency response illustrates the obtainable closed-loop bandwidths. For a closed-loop gain
of 2 the response peaks about 2dB. Peaking can be
minimized by keeping the feedback elements below 1kΩ,
and can be eliminated by placing a capacitor across the
feedback resistor, (feedback zero). This peaking shows
up as time domain overshoot of about 40%. With the
feedback capacitor it is eliminated.
Cable Terminations
The LT1193 video difference amplifier has been optimized
as a low cost cable driver. The ±50mA guaranteed output
current enables the LT1193 to easily deliver 7.5VP-P into
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8
LT1193
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APPLICATIO S I FOR ATIO
Small-Signal Transient Response
Closed-Loop Voltage Gain vs Frequency
CLOSED-LOOP VOLTAGE GAIN (dB)
25
VS = ±5V
TA = 25°C
AV = 10
AV = 5
15
AV = 3
AV = 2
5
–5
100k
1M
10M
FREQUENCY (Hz)
100M
LT1193 • TA10
AV = 2 WITH 8pF FEEDBACK CAPACITOR
RISE TIME = 3.75ns, RFB = 1k, RG = 1k
LT1193 • TA07
Closed-Loop Voltage Gain vs Frequency
8
VS = ±5V
TA = 25°C
AV = 2
RFB = 300Ω
RG = 300Ω
Double Terminated Cable Driver
5V
3 +
7
2 –
LT1193
1
CFB = 0pF
CFB = 5pF
8
6
RG
CFB = 10pF
CFB = 15pF
4
+
–
75Ω
6
4
–5V
CABLE
75Ω
RFB
CFB
2
Closed-Loop Voltage Gain vs Frequency
0
100k
8
1M
10M
FREQUENCY (Hz)
100M
LT1193 • TA08
Small-Signal Transient Response
CLOSED LOOP VOLTAGE GAIN (dB)
CLOSED-LOOP VOLTAGE GAIN (dB)
10
6
4
2
AV = 2
RFB = 300Ω
RG = 100Ω
CFB = 0pF
0
AV = 1
RFB = 300Ω
RG = 300Ω
CFB = 10pF
–2
–4
–6
100k
1M
10M
100M
FREQUENCY (Hz)
LT1193 • TA11
LT1193 • TA09
AV = 2, OVERSHOOT = 40%, RFB = 1k, RG = 1k
100Ω, while operating on ±5V supplies and gains > 3. On
a single 5V supply, the LT1193 can swing 2.6V P-P for
gains ≥ 2.
When driving a cable it is important to terminate the cable
to avoid unwanted reflections. This can be done in one of
two ways: single termination or double termination. With
single termination, the cable must be terminated at the
receiving end (75Ω to ground) to absorb unwanted energy. The best performance can be obtained by double
termination (75Ω in series with the output of the amplifier,
and 75Ω to ground at the other end of the cable). This
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9
LT1193
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APPLICATIO S I FOR ATIO
termination is preferred because reflected energy is absorbed at each end of the cable. When using the double
termination technique it is important to note that the signal
is attenuated by a factor of 2, or 6dB. The cable driver has
a – 3dB bandwidth of 80MHz while driving a 150Ω load.
Using the Shutdown Feature
The LT1193 has a unique feature that allows the amplifier
to be shut down for conserving power or for multiplexing
several amplifiers onto a common cable. The amplifier will
shut down by taking Pin 5 to V –. In shutdown, the amplifier
dissipates 15mW while maintaining a true high impedance
output state of 15kΩ in parallel with the feedback resistors. The amplifiers may be connected inverting, noninverting or differential for MUX applications. When the
output is loaded with as little as 1kΩ from the amplifier’s
feedback resistors, the amplifier shuts off in 200ns. This
shutoff can be under the control of HC CMOS operating
between 0V and – 5V.
isolating the capacitance with 10Ω can be helpful. Precautions primarily have to do with driving large
capacitive loads.
Other precautions include:
1. Use a ground plane (see Design Note 50, High Frequency Amplifier Evaluation Board).
2. Do not use high source impedances. The input capacitance of 2pF, and RS = 10k for instance, will give an
8MHz – 3dB bandwidth.
3. PC board socket may reduce stability.
4. A feedback resistor of 1k or lower reduces the effects of
stray capacitance at the inverting input. (For instance,
closed-loop gain of ±2 can use RFB = 300Ω and
RG = 300Ω.)
Driving Capacitive Load
Output Shutdown
tON = 300ns
tOFF = 200ns
LT1193 • TA14
AV = 2, IN DEMO BOARD, CL = 30pF, RFB = 1k, RG = 1k
LT1193 • TA12
1MHz SINE WAVE GATED OFF WITH
SHUTDOWN PIN, AV = 3, RFB = 1k, RG = 500Ω
Driving Capacitive Load
The ability to maintain shutoff is shown on the curve
Shutdown Supply Current vs Temperature in the Typical
Performance Characteristics section. At very high elevated temperatures it is important to hold the SHDN pin
close to the negative supply to keep the supply current
from increasing.
Murphy Circuits
There are several precautions the user should take when
using the LT1193 in order to realize its full capability.
Although the LT1193 can drive a 30pF in gains as low as␣ 2,
LT1193 • TA15
AV = 2, IN DEMO BOARD, CL = 30pF
WITH 10Ω ISOLATING RESISTOR
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Murphy Circuits
5V
3
2
1
8
+
–
+
–
5V
3
7
LT1193
6
2
COAX
1
8
4
+
–
+
–
–5V
5V
3
7
LT1193
2
6
1
4
8
1X SCOPE
PROBE
–5V
+
–
+
–
7
LT1193
6
4
–5V
SCOPE
PROBE
LT1193 • TA13
An Unterminated Cable Is
a Large Capacitive Load
A 1X Scope Probe Is a
Large Capacitive Load
A Scope Probe on the Inverting
Input Reduces Phase Margin
W
W
SI PLIFIED SCHE ATIC
7 V+
VBIAS
+
3
–
2
VBIAS
CM
C FF
+V
6 VOUT
+V
*
4 V–
5
SHDN
1 +/REF
8 –/FB
* SUBSTRATE DIODE, DO NOT FORWARD BIAS
LT1193 • TA16
1193fb
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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LT1193
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PACKAGE DESCRIPTIO
J8 Package
8-Lead CERDIP (Narrow .300 Inch, Hermetic)
.405
(10.287)
MAX
(Reference LTC DWG # 05-08-1110)
.300 BSC
(7.62 BSC)
.200
(5.080)
MAX
CORNER LEADS OPTION
(4 PLCS)
.008 – .018
(0.203 – 0.457)
.015 – .060
(0.381 – 1.524)
.023 – .045
(0.584 – 1.143)
HALF LEAD
OPTION
0° – 15°
.045 – .068
(1.143 – 1.650)
FULL LEAD
OPTION
.005
(0.127)
MIN
8
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE
OR TIN PLATE LEADS
.014 – .026
(0.360 – 0.660)
5
.025
(0.635)
RAD TYP
.220 – .310
(5.588 – 7.874)
1
.045 – .065
(1.143 – 1.651)
6
7
2
3
4
J8 0801
.125
3.175
MIN
.100
(2.54)
BSC
OBSOLETE PACKAGE
N8 Package
8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
.300 – .325
(7.620 – 8.255)
(
+.035
.325 –.015
+0.889
8.255
–0.381
.130 ± .005
(3.302 ± 0.127)
.045 – .065
(1.143 – 1.651)
.065
(1.651)
TYP
.008 – .015
(0.203 – 0.381)
)
.400*
(10.160)
MAX
8
7
6
5
1
2
3
4
.255 ± .015*
(6.477 ± 0.381)
.120
(3.048) .020
MIN
(0.508)
MIN
.018 ± .003
(0.457 ± 0.076)
.100
(2.54)
BSC
N8 1002
NOTE:
1. DIMENSIONS ARE
INCHES
MILLIMETERS
*THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
NOTE 3
.010 – .020
× 45°
(0.254 – 0.508)
.008 – .010
(0.203 – 0.254)
8
.004 – .010
(0.101 – 0.254)
.053 – .069
(1.346 – 1.752)
7
6
.045 ±.005
5
.050 BSC
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
NOTE:
1. DIMENSIONS IN
.014 – .019
(0.355 – 0.483)
TYP
INCHES
(MILLIMETERS)
2. DRAWING NOT TO SCALE
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
.050
(1.270)
BSC
.150 – .157
.245
(3.810 – 3.988) MIN
NOTE 3
.228 – .244
(5.791 – 6.197)
1
2
3
4
.030 ±.005
TYP
.160 ±.005
SO8 0303
RECOMMENDED SOLDER PAD LAYOUT
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1194
Video Difference Amp
AV = 10 Version of the LT1193
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12
Linear Technology Corporation
LT/TP 0903 1K REV B • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 1991
工商网监
湘ICP备2023018690号
