View LT1193_4105199.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

LT1193 Video Difference Amplifier
FEATURES
s s s s s s s s s s s s
DESCRIPTIO
Differential or Single-Ended Gain Block (Adjustable) -3dB Bandwidth, AV = 2: 80MHz Slew Rate: 500V/s 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 LT(R)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. The LT1193's high slew rate, 500V/s, 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. The LT1193 is available in 8-pin PDIP and SO packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
s s s s s
Line Receivers Video Signal Processing Cable Drivers Oscillators Tape and Disc Drive Systems
TYPICAL APPLICATIO
Cable Sense Amplifier for Loop Through Connections with DC Adjust
VIN 5V 3 CABLE VDC 2 1 8
+ - + -
7 LT1193 4 -5V 300
LT1193 * TA01
6
75 VOUT 75
300
U
1193fb
U
U
1
LT1193
ABSOLUTE
(Note 1)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW +/REF 1 -IN 2 +IN 3 V- 4 N8 PACKAGE 8-LEAD PDIP 8 7 6 5 -/FB V+ OUT SHDN
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) ................ - 55C to 125C LT1193C .................................................. 0C to 70C LT1193I ...............................................-40C to 85C Maximum Temperature ........................................ 150C Storage Temperature Range ................. - 65C to 150C Lead Temperature (Soldering, 10 sec).................. 300C
ORDER PART NUMBER LT1193CN8 LT1193CS8 LT1193IS8 S8 PART MARKING 1193 1193I LT1193MJ8 LT1193CJ8
S8 PACKAGE 8-LEAD PLASTIC SO
TJMAX = 150C, JA = 100C/W (N8) TJMAX = 150C, JA = 150C/W (S8)
J8 PACKAGE 8-LEAD CERDIP TJMAX = 150C, JA = 100C/W
OBSOLETE PACKAGE
Consider the N8 or S8 Packages for Alternate Source
Consult LTC Marketing for parts specified with wider operating temperature ranges.
VS = 5V, VREF = 0V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 from Pin 8 to ground, RL = RFB1 + RFB2 = 1k (Note 3), TA = 25C, 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 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 = 100 VO = 3V, RL = 1k RL = 100 VO = 2V, RL = 300 (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 = 150, AV = 2 (Note 9) RL = 150, AV = 2 (Note 9) MIN 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 A A nV/Hz pA/Hz k pF V V dB dB V V V % % V/s MHz MHz ns ns % ns % DegP-P
1193fb
ELECTRICAL CHARACTERISTICS
- 2.5 60 60 3.8 6.8 6.4
GE SR FPBW BW tr, t f tPD ts Diff AV Diff Ph
Gain Error Slew Rate Full-Power Bandwidth Small-Signal Bandwidth Rise Time, Fall Time Propagation Delay Overshoot Settling Time Differential Gain Differential Phase
350 18.5 110
2
U
W
U
U
WW
W
LT1193
ELECTRICAL CHARACTERISTICS
SYMBOL IS ISHDN tON tOFF PARAMETER Supply Current Shutdown Supply Current Shutdown Pin Current Turn On Time Turn Off Time
VS = 5V, VREF = 0V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 from Pin 8 to ground, RL = RFB1 + RFB2 = 1k (Note 3), TA = 25C, CL 10pF, Pin 5 open circuit, unless otherwise noted.
CONDITIONS Pin 5 at V- MIN LT1193M/C/I TYP MAX 35 1.3 20 300 200 Pin 5 at V - Pin 5 from V - to Ground, RL = 1k Pin 5 from Ground to V -, RL = 1k 43 2 50 UNITS mA mA A ns ns
VS+ = 5V, VS - = 0V, VREF = 2.5V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 from Pin 8 to VREF, RL = RFB1 + RFB2 = 1k (Note 3), TA = 25C, CL 10pF, Pin 5 open circuit, unless otherwise noted.
SYMBOL VOS IOS IB CMRR VOUT SR BW IS ISHDN PARAMETER Input Offset Voltage Input Offset Current Input Bias Current Input Voltage Range Common Mode Rejection Ratio Output Voltage Swing Slew Rate Small-Signal Bandwidth Supply Current Shutdown Supply Current Shutdown Pin Current Pin 5 at V- Pin 5 at V - VCM = 2V to 3.5V RL = 100 to Ground VO = 1V to 3V VOUT High VOUT Low CONDITIONS Both Inputs (Note 4) All Packages Either Input Either Input 2 55 3.6 70 3.8 0.25 250 8 32 1.3 20 40 2 50 0.4 MIN LT1193M/C/I TYP MAX 3 0.2 0.5 15 3 3.5 3.5 UNITS mV A A V dB V V V/s MHz mA mA A
The q denotes the specificatons which apply over the full operating temperature range of - 55C TA 125C. VS = 5V, VREF = 0V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 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 Pin 5 at V - (Note 10) Pin 5 at V- VCM = - 2.5V to 3.5V VS = 2.375V to 5V RL = 1k VS = 8V, RL = 100 VO = 3V, RL = 1k CONDITIONS
q q q q q q q q q q q q q
MIN
LT1193M TYP 2 20 0.8 1
MAX 16 5 5.5 3.5
UNITS mV V/C A A V dB dB V
-2.5 53 53 3.6 6 70 70 4 6.5 0.2 35 1.3 20
1.2 43 2.2
% mA mA A
1193fb
3
LT1193
ELECTRICAL CHARACTERISTICS
The q denotes the specificatons which apply over the full operating temperature range of - 40C TA 85C. VS = 5V, VREF = 0V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 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
q q q q q
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
VCM = - 2.5V to 3.5V VS = 2.375V to 5V RL = 1k VS = 8V, RL = 100 VO = 3V, RL = 1k Pin 5 at V - (Note 10) Pin 5 at V -
q q q q q q q q
-2.5 53 53 3.6 6
UNITS mV V/C A A V dB dB V % mA mA A
1.2 43 2.2
The q denotes the specificatons which apply over the full operating temperature range of 0C TA 70C. VS = 5V, VREF = 0V, RFB1 = 900 from Pins 6 to 8, RFB2 = 100 from Pin 8 to ground, RL = RFB1 + 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 N8 Package SO-8 Package MIN
q q q q q q
LT1193C TYP 2 20 0.2 0.5
MAX 14 20 3.5 4 3.5
VCM = - 2.5V to 3.5V VS = 2.375V to 5V RL = 1k RL = 100 VO = 3V, RL = 1k Pin 5 at V - (Note 10) Pin 5 at V -
q q q q q q q q
-2.5 55 55 3.7 6.2
70 70 4 6.6 0.2 35 1.3 20
1.2 43 2.1
UNITS mV mV V/C A A V dB dB V V % mA mA A
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 = 100 is specified, then an additional 100 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.
Note 7: Full-power bandwidth is calculated from the slew rate measurement: FPBW = SR/2VP. 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 > 125C. 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).
1193fb
4
LT1193 TYPICAL PERFOR A CE CHARACTERISTICS
Input Bias Current vs Common Mode Voltage
4 3 VS = 5V INPUT BIAS CURRENT (A) -0.3
COMMON MODE VOLTAGE (V)
INPUT BIAS CURRENT (A)
2 1 25C 0 -1 -2 -4 -3 1 3 -2 -1 0 2 COMMON MODE VOLTAGE (V) 4 -55C 125C
Equivalent Input Noise Voltage vs Frequency
EQUIVALENT INPUT NOISE CURRENT (pA/Hz)
EQUIVALENT INPUT NOISE VOLTAGE (nV/Hz)
400 350 300 250 200 150 100 50 0 10 100
SUPPLY CURRENT (mA)
1k 10k FREQUENCY (Hz)
Shutdown Supply Current vs Temperature
5.0 SHUTDOWN SUPPLY CURRENT (mA) 4.5 VS = 5V 3
3.5 3.0 VSHDN = -VEE + 0.2V 2.5 2.0 VSHDN = -VEE 1.5 1.0 -50 -25 0 25 75 50 TEMPERATURE (C) 100 125
1
RL = 100
OPEN-LOOP GAIN (V/V)
4.0
VSHDN = -VEE + 0.4V
GAIN ERROR (%)
UW
LT1193 * TPC01
Input Bias Current vs Temperature
VS = 5V 10 8 6 4 2 0 -2 -4 -6 -8 -0.8 -50 -10 -25 50 0 25 75 TEMPERATURE (C) 100 125
Common Mode Voltage vs Supply Voltage
-55C 25C +V COMMON MODE 125C
-0.4 +IB -0.5 IOS -0.6 -IB
-0.7
-V COMMON MODE
-55C 25C 125C
0
2
6 4 8 V SUPPLY VOLTAGE (V)
10
LT1193 * TPC02
LT1193 * TPC03
Equivalent Input Noise Current vs Frequency
80 VS = 5V TA = 25C RS = 100k 50
Supply Current vs Supply Voltage
VS = 5V TA = 25C RS = 0
60
40 -55C 30 25C 125C 20
40
20
10
0 10 100 1k 10k FREQUENCY (Hz) 100k
0 0 2 4 6 8 SUPPLY VOLTAGE (V) 10
100k
LT1193 * TPC04
LT1193 * TPC05
LT1193 * TPC06
Gain Error vs Temperature
VS = 5V
Open-Loop Gain vs Temperature
20k VS = 5V VO = 3V RL = 1k
2
15k
0
RL = 1k
10k
5k RL = 100
-1
-2 -50 -25
25 0 50 75 TEMPERATURE (C)
100
125
0 -50 -25
25 75 0 50 TEMPERATURE (C)
100
125
LT1193 * TPC07
LT1193 * TPC08
LT1193 * TPC09
1193fb
5
LT1193 TYPICAL PERFOR A CE CHARACTERISTICS
Gain, Phase vs Frequency
100 80 100 80 60 40 20 0 -20 100M
LT1193 * TPC11
PHASE
15k
GAIN BANDWIDTH PRODUCT (MHz)
OPEN-LOOP VOLTAGE GAIN (V/V)
VOLTAGE GAIN (dB)
60 40 20 0 VS = 5V TA = 25C RL = 1k -20 100k
GAIN
1M 10M FREQUENCY (Hz)
Gain Bandwidth Product and Unity Gain Phase Margin vs Temperature
70
GAIN BANDWIDTH PRODUCT (MHz)
65 60 55 50 45 40 35 30 -50 -25 25 75 0 50 TEMPERATURE (C) GAIN BANDWIDTH PRODUCT
65 60 55 50
OUTPUT IMPEDANCE ( )
COMMON MODE REJECTION RATIO (dB)
UNITY GAIN PHASE MARGIN
Power Supply Rejection Ratio vs Frequency
80 OUTPUT SHORT-CIRCUIT CURRENT (mA)
POWER SUPPLY REJECTION RATIO (dB)
60 +PSRR -PSRR
VS = 5V TA = 25 C VRIPPLE = 300mV
90
40
OUTPUT SWING (V)
20
0
-20 1k 10k 1M 100k FREQUENCY (Hz) 10M 100M
6
UW
VS = 5V RL = 1k 100
LT1193 * TPC13
Open-Loop Voltage Gain vs Load Resistance
20k VS = 5V VO = 3V TA = 25C 80
Gain Bandwidth Product vs Supply Voltage
PHASE MARGIN (DEGREES) PHASE MARGIN (DEGREES)
70
10k
TA = -55C, 25C, 125C 60
5k
0 10 100 LOAD RESISTANCE () 1000
LT1193 * TPC10
50 0 2 6 4 8 SUPPLY VOLTAGE (V) 10
LT1193 * TPC12
Output Impedance vs Frequency
100 VS = 5V TA = 25C
80
Common Mode Rejection Ratio vs Frequency
VS = 5V TA = 25C RL = 1k
70
10 AV = 10
70
1
60
45 40 35 30 125
0.1
AV = 2
50
0.01
40
0.001
1k
10k
100k 1M FREQUENCY (Hz)
10M
100M
30 100k
1M 10M FREQUENCY (Hz)
100M
LT1193 * TPC15
LT1193 * TPC14
Output Short-Circuit Current vs Temperature
100 VS = 5V 10 8 6 4 2 0 -2 -4 -6 -8 70 -50 -10 -25 50 0 25 75 TEMPERATURE (C) 100 125
Output Swing vs Supply Voltage
RL = 1k +VOUT, 25C, 125C, -55C
80
-VOUT, -55C, 25C, 125C
0
2
8 4 6 V SUPPLY VOLTAGE (V)
10
LT1193 * TPC16
LT1193 * TPC17
LT1193 * TPC18
1193fb
LT1193 TYPICAL PERFOR A CE CHARACTERISTICS
Output Voltage Swing vs Load Resistance
5 VS = 5V TA = -55C 900 800 - SLEW RATE
OUTPUT VOLTAGE SWING (V)
OUTPUT VOLTAGE STEP (V)
3
SLEW RATE (V/s)
1
TA = 25C TA = 125C
-1
-3
TA = 125C TA = -55C, 25C
-5 10 100 LOAD RESISTANCE () 1000
LT1193 * TPC19
Large-Signal Transient Response
AV = 2, RL = 150, RFB = 300, RG = 300
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
U
W
UW
LT1193 * TPC22
Slew Rate vs Temperature
4
Output Voltage Step vs Settling Time, AV = 2
VS = 5V TA = 25C RL = 1k 10mV
2
700 600 500 +SLEW RATE
0
VS = 5V 400 TA = 25C RL = 1k VO = 2V 300 -50 -25 0 25 50 75 TEMPERATURE (C)
-2 10mV
-4 100 125 40 50 60 70 80 SETTLING TIME (ns) 90 100
LT1193 * TPC20
LT1193 * TPC21
Small-Signal Transient Response
Small-Signal Transient Response
LT1193 * TPC23
LT1193 * TPC24
AV = -10, SMALL-SIGNAL RISE TIME = 43ns
AV = 2, RFB = 300, RG = 300, OVERSHOOT = 25%, RISE TIME = 4.7ns
UU
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 0.1F 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.
1193fb
7
LT1193
APPLICATIO S I FOR ATIO
SHDN VIN 3 2 5 V+ 3 2 SHDN 5 V+ 7 + - LT1193 6 VIN 7 + - LT1193
1 +/REF 8 -/FB 4
VOUT
1 +/REF 8 -/FB 4
V- RFB RG R + RG AV = + FB RG RG
V- RFB R + RG AV = - FB RG SHDN
SHDN 3 2 5 V+ VINDIFF VOUT VIN RG 3 2 7 + - LT1193
5
V+
LT1192 * TA05
VINDIFF VIN
1 +/REF 8 -/FB 4
6
1 +/REF 8 -/FB 4
7 + - LT1193
V- RFB R + RG VO = (VINDIFF + VIN) FB RG RG
FB G
V- RFB
VO =
(R R+ R ( V
G
INDIFF -
No Supply Bypass Capacitors
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 0.1F ceramic disc in parallel with a 4.7F 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 0.1F bypass; the time drops to 96ns with multiple bypass capacitors.
8
U
Settling Time Poor Bypass
6 VOUT
W
UU
VOUT 1V/DIV 0V
0V VOUT 10mV/DIV
6
VOUT
SETTLING TIME TO 10mV, AV = 2 SUPPLY BYPASS CAPACITORS = 0.1F
Settling Time Good Bypass
( RR ( V
FB G
IN
LT1193 * TA03
VOUT 1V/DIV 0V
0V VOUT 10mV/DIV
LT1192 * TA06
SETTLING TIME TO 10mV, AV = 2 SUPPLY BYPASS CAPACITORS = 0.1F + 4.7F TANTALUM
Operating With Low Closed-Loop Gains 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 1k, 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
1193fb
LT1193
APPLICATIO S I FOR ATIO
Closed-Loop Voltage Gain vs Frequency
25
CLOSED-LOOP VOLTAGE GAIN (dB)
AV = 10
VS = 5V TA = 25C
15
AV = 5 AV = 3 AV = 2
5
-5 100k
1M 10M FREQUENCY (Hz)
100M
LT1193 * TA07
Closed-Loop Voltage Gain vs Frequency
10
CLOSED-LOOP VOLTAGE GAIN (dB)
8
VS = 5V TA = 25C AV = 2 RFB = 300 RG = 300
CFB = 0pF CFB = 5pF
6 CFB = 10pF 4 CFB = 15pF
RG
2
CLOSED LOOP VOLTAGE GAIN (dB)
0 100k
1M 10M FREQUENCY (Hz)
100M
LT1193 * TA08
Small-Signal Transient Response
LT1193 * TA09
AV = 2, OVERSHOOT = 40%, RFB = 1k, RG = 1k
100, while operating on 5V supplies and gains > 3. On a single 5V supply, the LT1193 can swing 2.6V P-P for gains 2.
U
Small-Signal Transient Response
LT1193 * TA10
W
UU
AV = 2 WITH 8pF FEEDBACK CAPACITOR RISE TIME = 3.75ns, RFB = 1k, RG = 1k
Double Terminated Cable Driver
5V 3+ 7 2- LT1193 1 8 6 75 CABLE 75
+ -
4 -5V
RFB CFB
Closed-Loop Voltage Gain vs Frequency
8 6 4 2 0 -2 -4 -6 100k AV = 1 RFB = 300 RG = 300 CFB = 10pF AV = 2 RFB = 300 RG = 100 CFB = 0pF
1M
10M
100M
LT1193 * TA11
FREQUENCY (Hz)
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 (75 to ground) to absorb unwanted energy. The best performance can be obtained by double termination (75 in series with the output of the amplifier, and 75 to ground at the other end of the cable). This
1193fb
9
LT1193
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 150 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 15k 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 1k 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.
Output Shutdown
tON = 300ns
tOFF = 200ns
LT1193 * TA12
1MHz SINE WAVE GATED OFF WITH SHUTDOWN PIN, AV = 3, RFB = 1k, RG = 500
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
10
U
isolating the capacitance with 10 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 = 300 and RG = 300.)
Driving Capacitive Load
LT1193 * TA14
W
UU
AV = 2, IN DEMO BOARD, CL = 30pF, RFB = 1k, RG = 1k
Driving Capacitive Load
AV = 2, IN DEMO BOARD, CL = 30pF WITH 10 ISOLATING RESISTOR
1193fb
LT1193
APPLICATIO S I FOR ATIO
5V 3 2 1 8
+ - + -
7 LT1193 4 -5V 6
COAX
An Unterminated Cable Is a Large Capacitive Load
SI PLIFIED SCHE ATIC
7 V+ VBIAS VBIAS
+ -
3 C FF 2 +V +V
5 SHDN 1 +/REF 8 -/FB * SUBSTRATE DIODE, DO NOT FORWARD BIAS
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.
U
Murphy Circuits
5V 3 2 1 8
W
W
UU
+ - + -
5V 3 6 2 1
7 LT1193 4 -5V
+ - + -
7 LT1193 4 -5V 6
1X SCOPE PROBE
8
SCOPE PROBE
LT1193 * TA13
A 1X Scope Probe Is a Large Capacitive Load
A Scope Probe on the Inverting Input Reduces Phase Margin
W
CM
6 VOUT
*
4 V-
LT1193 * TA16
1193fb
11
LT1193
PACKAGE DESCRIPTIO U
J8 Package 8-Lead CERDIP (Narrow .300 Inch, Hermetic)
(Reference LTC DWG # 05-08-1110)
.300 BSC (7.62 BSC) CORNER LEADS OPTION (4 PLCS) .200 (5.080) MAX .015 - .060 (0.381 - 1.524) .005 (0.127) MIN 8 .405 (10.287) MAX 7 6 5 .023 - .045 (0.584 - 1.143) HALF LEAD OPTION .025 (0.635) RAD TYP 1 .045 - .065 (1.143 - 1.651) .014 - .026 (0.360 - 0.660) .100 (2.54) BSC .125 3.175 MIN 2 3 .220 - .310 (5.588 - 7.874) 4
J8 0801
.008 - .018 (0.203 - 0.457)
0 - 15
.045 - .068 (1.143 - 1.650) FULL LEAD OPTION
NOTE: LEAD DIMENSIONS APPLY TO SOLDER DIP/PLATE OR TIN PLATE LEADS
OBSOLETE PACKAGE
N8 Package 8-Lead PDIP (Narrow .300 Inch)
(Reference LTC DWG # 05-08-1510)
.300 - .325 (7.620 - 8.255) .045 - .065 (1.143 - 1.651) .130 .005 (3.302 0.127) .400* (10.160) MAX 8 7 6 5
.008 - .015 (0.203 - 0.381)
.065 (1.651) TYP .120 (3.048) .020 MIN (0.508) MIN .018 .003 (0.457 0.076)
.255 .015* (6.477 0.381)
(
+.035 .325 -.015 +0.889 8.255 -0.381
)
1
2
3
4
N8 1002
.100 (2.54) BSC
INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm)
NOTE: 1. DIMENSIONS ARE
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 x 45 (0.254 - 0.508) .008 - .010 (0.203 - 0.254) .053 - .069 (1.346 - 1.752) 0- 8 TYP .228 - .244 (5.791 - 6.197) .150 - .157 .245 (3.810 - 3.988) MIN NOTE 3 .160 .005 .004 - .010 (0.101 - 0.254) 8 7 6 5 .050 BSC
.045 .005
.016 - .050 (0.406 - 1.270) NOTE: 1. DIMENSIONS IN
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)
.014 - .019 (0.355 - 0.483) TYP
.050 (1.270) BSC
1
2
3
4
.030 .005 TYP
SO8 0303
RECOMMENDED SOLDER PAD LAYOUT
RELATED PARTS
PART NUMBER LT1194 DESCRIPTION Video Difference Amp COMMENTS AV = 10 Version of the LT1193
1193fb LT/TP 0903 1K REV B * PRINTED IN USA
12
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 q FAX: (408) 434-0507
q
www.linear.com
(c) LINEAR TECHNOLOGY CORPORATION 1991

▲Up To Search▲

Price & Availability of LT1193

	To Download LT1193 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .