LT6552
3.3V Single Supply
Video Difference Amplifier
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FEATURES
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DESCRIPTIO
Differential or Single-Ended Gain Block
Wide Supply Range 3V to 12.6V
Output Swings Rail-to-Rail
Input Common Mode Range Includes Ground
600V/µs Slew Rate
–3dB Bandwidth = 75MHz, AV = ±2
CMRR at 10MHz: >60dB
Specified on 3.3V, 5V and ±5V Supplies
High Output Drive: ±70mA
Power Shutdown to 300µA
Operating Temperature Range: –40°C to 85°C
Available in 8-Lead SO and
Tiny 3mm x 3mm x 0.8mm DFN Packages
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APPLICATIO S
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Differential to Single-Ended Conversion
Video Line Driver
Automotive Displays
RGB Amplifiers
Coaxial Cable Drivers
Low Voltage High Speed Signal Processing
On a single 3.3V supply, the input voltage range extends
from ground to 1.3V and the output swings from ground
to 2.9V while driving a 150Ω load. The LT6552 features
75MHz – 3dB bandwidth, 600V/µs slew rate, and ±70mA
output current making it ideal for driving cables directly.
The LT6552 maintains its performance for supplies from
3V to 12.6V and is fully specified at 3.3V, 5V and ±5V
supplies. The shutdown feature reduces power dissipation to less than 1mW and allows multiple amplifiers to
drive the same cable.
The LT6552 is available in the 8-lead SO package as well
as a tiny, dual fine pitch leadless package (DFN). The
device is specified over the commercial and industrial
temperature ranges.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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The LT®6552 is a video difference amplifier optimized for
low voltage single supply operation. This versatile amplifier features uncommitted high input impedance (+) and
(–) inputs and can be used in differential or single-ended
configurations. A second set of inputs gives gain adjustment and DC control to the differential amplifier.
TYPICAL APPLICATIO
Input Referred CMRR vs Frequency
Cable Sense Amplifier for Loop Through
Connections with DC Adjust
VIN
5V
3
2
CABLE
VDC
7
+
– LT6552
1
REF
8
FB
6
4
75Ω
VOUT
75Ω
RF
500Ω
RG
500Ω
6552 TA01a
CF
8pF
COMMON MODE REJECTION RATIO (dB)
100
90
VS = 5V, 0V
VCM = 0V DC
80
70
60
50
40
30
20
10
100k
1
10
FREQUENCY (MHz)
100
6552 TA01b
6552f
1
LT6552
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ABSOLUTE
AXI U RATI GS (Note 1)
Supply Voltage (V + to V –) .................................... 12.6V
Input Current (Note 2) ........................................ ±10mA
Input Voltage Range ......................................... V – to V +
Differential Input Voltage
+Input (Pin 3) to –Input (Pin 2) ................................ ±VS
Output Short-Circuit Duration (Note 3) ............ Indefinite
Operating Temperature Range (Note 4) ...–40°C to 85°C
Specified Temperature Range (Note 5) ....–40°C to 85°C
Maximum Junction Temperature .......................... 150°C
(DD Package) ................................................... 125°C
Storage Temperature Range ..................–65°C to 150°C
(DD Package) ....................................–65°C to 125°C
Lead Temperature
(Soldering, 10 sec) ........................................... 300°C
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W
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
REF
1
8
FB
–IN
2
7
V+
+IN
3
6
OUT
V–
4
5
SHDN
DD PACKAGE
8-LEAD (3mm × 3mm) PLASTIC DFN
TJMAX = 125°C, θJA = 160°C/W
UNDERSIDE METAL CONNECTED TO V–
(PCB CONNECTION OPTIONAL)
LT6552CDD
LT6552IDD
ORDER PART
NUMBER
TOP VIEW
REF 1
8
FB
–IN 2
7
V+
+IN 3
6
OUT
V– 4
5
SHDN
DD PART MARKING*
LADR
LT6552CS8
LT6552IS8
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
TJMAX = 150°C, θJA = 100°C/W
6552
6552I
*The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for parts specified with wider operating temperature ranges.
3.3V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full
operating temperature range, otherwise specifications are at TA = 25°C. VS = 3.3V, 0V. Figure 1 shows the DC test circuit,
VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage
Both Inputs (Note 7)
MIN
TYP
MAX
5
20
25
●
UNITS
mV
mV
∆VOS/∆T
Input VOS Drift
●
40
IB
Input Bias Current
Any Input
●
20
50
µV/°C
µA
IOS
Input Offset Current
Either Input Pair
●
1
5
µA
6552f
2
LT6552
3.3V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full
operating temperature range, otherwise specifications are at TA = 25°C. VS = 3.3V, 0V. Figure 1 shows the DC test circuit,
VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
en
Input Noise Voltage Density
f = 10kHz
in
Input Noise Current Density
RIN
Input Resistance
CMRR
Common Mode Rejection Ratio
VCM = 0V to 1.3V
PSRR
Power Supply Rejection
MIN
UNITS
nV/√Hz
f = 10kHz
0.7
pA/√Hz
Common Mode, VCM = 0V to 1.3V
300
kΩ
83
dB
VS = 3V to 12V
Minimum Supply (Note 8)
●
0
●
48
●
3
Gain Error
VO = 0.5V to 2V, RL = 1k
RL = 150Ω
●
●
VOH
Swing High
(VDIFF = 0.4V), VREF (Pin 1) = 0V, AV = 10
RL = 1k
RL = 150Ω
RL = 75Ω
●
●
(VDIFF = –0.1V), VREF(Pin 1) = 0V, AV = 10
RL = 1k
ISINK = 5mA
ISINK = 10mA
58
●
GE
Swing Low
MAX
55
Input Range
VOL
TYP
1.3
54
V
1
1
3.1
2.5
2
3
3
3.2
2.9
2.5
8
65
40
●
●
●
V
dB
%
%
V
V
V
50
120
200
mV
mV
mV
SR
Slew Rate
VOUT = 0.5V to 2.5V Measure from 1V to 2V,
RL = 150Ω, AV = 2
350
V/µs
FPBW
Full-Power Bandwidth (Note 9)
VO = 2VP-P
55
MHz
BW
Small-Signal –3dB Bandwidth
AV = 2, RL = 150Ω
65
MHz
tr, tf
Rise Time, Fall Time (Note 10)
AV =50, VO = 0.5V to 2.5V,
20% to 80%, RL = 150Ω
125
tS
Settling Time to 3%
Settling Time to 1%
AV = 2, ∆VOUT = 2V, Positive Step
RL = 150Ω
20
30
ISC
ns
ns
ns
Differential Gain
AV = 2, RL = 150Ω, Output Black Level = 0.6V
0.4
%
Differential Phase
AV = 2, RL = 150Ω, Output Black Level = 0.6V
0.15
Deg
Short-Circuit Current
VOUT = 0V, VDIFF = 1V
50
mA
mA
●
IS
175
35
25
Supply Current
12.5
13.5
15
mA
mA
300
750
µA
0.5
V
●
Supply Current, Shutdown
VSHDN = 0.5V
●
VL
Shutdown Pin Input Low Voltage
●
VH
Shutdown Pin Input High Voltage
●
Shutdown Pin Current
VSHDN = 0.5V
VSHDN = 3V
tON
Turn On-Time
VSHDN from 0.5V to 3V
tOFF
Turn Off-Time
VSHDN from 3V to 0.5V
Shutdown Output Leakage Current
VSHDN = 0.5V, 0V ≤ VOUT ≤ V+
●
●
3
V
40
3
250
●
150
10
µA
µA
ns
450
ns
0.25
µA
6552f
3
LT6552
5V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VS = 5V, 0V; Figure 1 shows the DC test circuit,
VREF = VCM = 1V, VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage
Both Inputs (Note 7)
MIN
TYP
MAX
5
20
25
●
UNITS
mV
mV
∆VOS/∆T
Input VOS Drift
IB
Input Bias Current
IOS
Input Offset Current
en
Input Noise Voltage Density
f = 10kHz
55
nV/√Hz
in
Input Noise Current Density
f = 10kHz
0.7
pA/√Hz
RIN
Input Resistance
Common Mode, VCM = 0V to 3V
300
kΩ
CMRR
Common Mode Rejection Ratio
VCM = 0V to 3V
40
Any Input
●
20
50
uA
Either Input Pair
●
1
5
uA
Input Range
PSRR
Power Supply Rejection
VS = 3V to 12V
Minimum Supply (Note 8)
●
58
●
0
●
48
●
3
GE
Gain Error
VO = 0.5V to 3.5V, RL = 1k
RL = 150Ω
●
●
VOH
Swing High
(VDIFF = 0.6V), VREF(Pin 1) = 0V, AV = 10
RL = 1k
RL = 150Ω
RL = 75Ω, 0°C ≤ TA ≤ 70°C (Only)
●
●
●
(VDIFF = –0.1V), VREF (Pin 1) = 0V, AV = 10
RL = 1k
ISINK = 5mA
ISINK = 10mA
●
●
●
VOL
SR
FPBW
Swing Low
Slew Rate
Full-Power Bandwidth (Note 9)
µV/°C
●
83
54
V
dB
V
1
1
4.8
3.6
2.75
dB
3
3
3
4.875
4.3
3.4
8
65
110
%
%
V
V
V
50
120
200
mV
mV
mV
VOUT = 0.5V to 3.5V
Measure from 1V to 3V, RL = 150Ω, AV = 2
450
V/µs
VO = 2VP-P
70
MHz
BW
Small-Signal –3dB Bandwidth
AV = 2, RL = 150Ω
70
tr, tf
Rise Time, Fall Time
5V, 0V; AV = 50, VO = 0.5V to 3.5V,
20% to 80%, RL = 1k
125
tS
Settling Time to 3%
Settling Time to 1%
AV = 2, ∆VOUT = 2V, Positive Step
RL = 150Ω
20
30
ns
ns
Differential Gain
AV = 2, RL = 150Ω, Output Black Level = 1V
0.25
%
Differential Phase
AV = 2, RL = 150Ω, Output Black Level = 1V
0.04
Deg
Short-Circuit Current
VOUT = 0V, VDIFF = 1V
0°C ≤ TA ≤ 70°C
–40°C ≤ TA ≤ 85°C
70
mA
mA
mA
ISC
IS
●
●
50
45
35
Supply Current
VSHDN = 0.5V
●
VL
Shutdown Pin Input Low Voltage
●
VH
Shutdown Pin Input High Voltage
●
Shutdown Pin Current
VSHDN = 0.5V
VSHDN = 4.7V
●
●
ns
13.5
14.5
16
mA
mA
400
900
µA
●
Supply Current Shutdown
MHz
175
0.5
4.7
V
V
60
4
200
10
µA
µA
6552f
4
LT6552
5V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VS = 5V, 0V. Figure 1 shows the DC test circuit, VREF = VCM = 1V,
VDIFF = 0V, VSHDN = V+, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
tON
Turn-On Time
VSHDN from 0.5V to 4.7V
250
ns
tOFF
Turn-Off Time
VSHDN from 4.7V to 0.5V
450
ns
0.25
µA
Shutdown Output Leakage Current
VSHDN = 0.5V, 0V ≤ VOUT
MIN
≤ V+
●
TYP
MAX
UNITS
±5V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VS = ±5V. Figure 2 shows the DC test circuit, VREF = VCM = 0V,
VDIFF = 0V, VSHDN = V +, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
VOS
Input Offset Voltage
Both Inputs (Note 7)
MIN
TYP
MAX
10
25
30
●
UNITS
mV
mV
∆VOS/∆T
Input VOS Drift
µV/°C
IB
Input Bias Current
IOS
Input Offset Current
en
Input Noise Voltage Density
f = 10kHz
55
nV/√Hz
in
Input Noise Current Density
f = 10kHz
0.7
pA/√Hz
RIN
Input Resistance
Common Mode, VCM = –5V to 3V
300
kΩ
CMRR
Common Mode Rejection Ratio
VCM = –5V to 3V
75
dB
PSRR
Power Supply Rejection
VS = ±2V to ±6V, VCM = 0V
GE
Gain Error
VO = –3V to 3V, RL = 1k
RL = 150Ω
●
●
Output Voltage Swing
(VDIFF = ± 0.6V), VREF (Pin 1) = 0V, AV = 10
RL = 1k
RL = 150Ω
RL = 75Ω, 0°C ≤ TA ≤ 70°C (Only)
●
●
●
●
50
Any Input
●
25
50
µA
Either Input Pair
●
1
5
µA
Input Range
●
58
●
–5
●
48
1
1
V
dB
3
3
%
%
±4.8
±3.6
±2.75
±4.875
±4.3
±3.4
400
600
V/µs
V
V
V
SR
Slew Rate
FPBW
Full-Power Bandwidth
VO = 6VP-P (Note 9)
30
MHz
BW
Small-Signal –3dB Bandwidth
AV = 2, RL = 150Ω
75
MHz
tr, tf
Rise Time, Fall Time
AV = 50, VO = –3V to 3V, 20% to 80%
125
tS
Settling Time to 3%
Settling Time to 1%
AV = 2, ∆VOUT = 6V, Positive Step
RL = 150Ω
25
35
ns
ns
Differential Gain
AV = 2, RL = 150Ω, Output Black Level = 0V
0.2
%
Differential Phase
AV = 2, RL = 150Ω, Output Black Level = 0V
0.15
Deg
Short-Circuit Current
VOUT = 0V, VDIFF = ±1V
0°C ≤ TA ≤ 70°C
–40°C ≤ TA ≤ 85°C
70
●
●
mA
mA
mA
VSHDN = –4.5V
●
ISC
Supply Current Shutdown
IS
VCM = 0V, VDIFF = –1.5V to +1.5V,
VO = –5V to 5V Measure from –2V to 2V, RL = 150Ω
3
54
50
45
35
Supply Current
●
VL
Shutdown Pin Input Low Voltage
●
VH
Shutdown Pin Input High Voltage
●
4.7
175
ns
650
1400
µA
14
16.5
18.5
mA
mA
–4.5
V
V
6552f
5
LT6552
±5V ELECTRICAL CHARACTERISTICS
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VS = ±5V. Figure 2 shows the DC test circuit, VREF = VCM = 0V,
VDIFF = 0V, VSHDN = V +, unless otherwise noted. RL = RF + RG = 1k. (Note 6)
SYMBOL
PARAMETER
CONDITIONS
Shutdown Pin Current
VSHDN = –4.5V
VSHDN = 4.7V
tON
Turn-On Time
VSHDN from – 4.5V to 4.7V
tOFF
Turn-Off Time
VSHDN from 4.7V to –4.5V
Shutdown Output Leakage Current
VSHDN = –4.5V, V – ≤ VOUT ≤ V+
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The inputs are protected from ESD with diodes to the supplies.
Note 3: A heat sink may be required to keep the junction temperature
below absolute maximum.
Note 4: The LT6552C/LT6552I are guaranteed functional over the
temperature range of –40°C to 85°C.
Note 5: The LT6552C is guaranteed to meet specified performance from
0°C to 70°C and is designed, characterized and expected to meet specified
performance from –40°C to 85°C, but is not tested or QA sampled at these
temperatures. The LT6552I is guaranteed to meet specified performance
from – 40°C to 85°C.
MIN
–+
FB
–IN
V+
V–
VREF
+
–
+
–
VCM
UNITS
85
3
250
10
µA
µA
200
●
ns
400
ns
0.25
µA
Note 6: When RL = 1k is specified, the load resistor is RF + RG, but when
RL = 150Ω or RL = 75Ω is specified, then an additional resistor of that
value is added to the output.
Note 7: VOS measured at the output (Pin 6) is the contribution from both
input pairs and is input referred.
Note 8: Minimum supply is guaranteed by the PSRR test.
Note 9: Full power bandwidth is calculated from the slew rate.
FPBW = SR/2πVp
Note 10: VS = 3.3V, tr and tf limits are guaranteed by correlation to
VS = 5V and ±5V tests.
RG
100Ω
0.1%
REF
+IN
MAX
●
●
RG
100Ω
0.1%
VDIFF
TYP
1µF
OUT
RF
900Ω
0.1%
–
+
SHDN
VSHDN
+
–
+
–
V+
RL
+
–
VDIFF
VCM
–
+
REF
FB
–IN
V+
+IN
V–
V–
1µF
1µF
OUT
SHDN
VSHDN
+
–
+
–
6552 F01
Figure 1. 3.3V, 5V DC Test Circuit
RF
900Ω
0.1%
V+
RL
6552 F02
Figure 2. ±5V DC Test Circuit
6552f
6
LT6552
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current vs Supply Voltage
–10
18
14
INPUT BIAS CURRENT (µA)
SUPPLY CURRENT (mA)
–12
TA = 125°C
TA = –55°C
12
TA = 25°C
10
8
6
4
–4
VS = 5V, 0V
VCM = 1V
–14
–16
–18
–20
–22
2
2
0
6
8
10
4
TOTAL SUPPLY VOLTAGE (V)
12
50
25
75
0
TEMPERATURE (°C)
100
TA = 125°C
–12
TA = 25°C
–14
–16
TA = –55°C
–18
–20
Output Saturation Voltage vs
Load Current (Output High)
Output Saturation Voltage vs
Load Current (Output Low)
1
OUTPUT LOW SATURATION VOLTAGE (V)
VS = 5V, 0V
TA = 125°C
100m
TA = 25°C
TA = –55°C
10m
0.01
0.1
1
10
SOURCING LOAD CURRENT (mA)
100m
TA = 125°C
TA = –55°C
TA = 25°C
0.1
1
10
SINKING LOAD CURRENT (mA)
TA = 25°C
–40
TA = –55°C
–50
–60
0
1
2
3
4
SHUTDOWN PIN VOLTAGE (V)
8
6
4
5
6552 G07
3.0
3.5
4.5
4.0
SHUTDOWN PIN VOLTAGE (V)
70
Output Short-Circuit Current vs
Temperature
80
VS = 5V, 0V
65
60
55
VS = 3.3V, 0V
50
45
40
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
5.0
6552 G06
OUTPUT SHORT-CIRCUIIT CURRENT (mA)
OUTPUT SHORT-CIRCUIIT CURRENT (mA)
–30
TA = –55°C
10
0
2.5
100
75
TA = 125°C
–20
TA = 25°C
12
Output Short-Circuit Current vs
Temperature
–10
TA = 125°C
6552 G05
Shutdown Pin Current vs
Shutdown Pin Voltage
VS = 5V, 0V
VCM = 1V
VS = 5V, 0V
VCM = 1V
2
1m
0.01
100
16
VS = 5V, 0V
14
10m
5
Supply Current vs
Shutdown Pin Voltage
6552 G04
0
1
3
4
2
COMMON MODE VOLTAGE (V)
0
6552 G03
SUPPLY CURRENT (mA)
1
–24
125
6552 G02
6552 G01
OUTPUT HIGH SATURATION VOLTAGE (V)
–8
–10
–22
–24
–50 –25
0
SHUTDOWN PIN CURRENT (µA)
VS = 5V, 0V
–6
INPUT BIAS CURRENT (µA)
20
16
Input Bias Current vs Common
Mode Voltage
Input Bias Current vs Temperature
125
6552 G08
VS = ±5V
SOURCING CURRENT
75
SINKING CURRENT
70
65
60
–50 –25
50
25
75
0
TEMPERATURE (°C)
100
125
6552 G09
6552f
7
LT6552
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Input Noise Voltage Density vs
Frequency
Open-Loop Gain
225
400
300
200
100
RL = 1k
RL = 150Ω
–200
–300
–400
150
125
100
75
50
25
100
–500
–5 –4 –3 –2 –1 0 1 2 3
OUTPUT VOLTAGE (V)
4
5
1k
10k
FREQUENCY (Hz)
Closed-Loop Voltage Gain vs
Frequency
6.2
CLOSED-LOOP VOLTAGE GAIN (dB)
7
6
3.3V
5
VIN
4
VDC
3
2
3
2
7
+
– LT6552
1
REF
8
FB
4
6
RF
500Ω
VOUT
RL
150Ω
RG
500Ω
1
0
100k
1M
10M
FREQUENCY (Hz)
6.1
6.0
5.9
5.8
VDC
3
2
70
60
50
7
+
– LT6552
1
REF
8
FB
4
6
RF
500Ω
VOUT
RL
150Ω
RG
500Ω
5.7
10k
100M
100
VS = 3.3V, OV
VCM = 1V
100k
CL = 5pF
RL = 1k
VS = ±5V
30
40
10
–10
VS = ±5V
100M
30
100
20
0
–20
GAIN
–20
1M
10M
FREQUENCY (Hz)
VS = 3.3V, OV 80
VCM = 1V
60
20
0
–30
100k
1M
10M
FREQUENCY (Hz)
130
100M
20
125
6552 G16
40
PHASE MARGIN
0
2
AV = 2
RL = 150Ω
80
GAIN BANDWIDTH PRODUCT
110
–60
500M
–3dB Bandwidth vs Temperature
85
CL = 5pF
RL = 1k
TA = 25°C
VCM =1V
120
–40
6552 G15
30
8
6
4
10
12
TOTAL SUPPLY VOLTAGE (V)
20
14
6552 G17
PHASE MARGIN (DEG)
VS = ±5V
PHASE MARGIN (DEG)
40
PHASE MARGIN
50
25
75
0
TEMPERATURE (°C)
VS = ±5V
VS = 3.3V, OV
VCM = 1V
80
–50 –25
PHASE
40
Gain Bandwidth Product and
Phase Margin vs Supply Voltage
VS = 3.3V, OV
VCM = 1V
100k
140
CL = 5pF
120
RL = 1k
TA = 25°C 100
6552 G14
GAIN BANDWIDTH
PRODUCT (MHz)
GAIN BANDWIDTH
PRODUCT (MHz)
120
1k
10k
FREQUENCY (Hz)
Open-Loop Gain and Phase vs
Frequency
3.3V
VIN
Gain Bandwidth Product and
Phase Margin vs Temperature
GAIN BANDWIDTH PRODUCT
0
100
AV = 2
VOUT = 1.5V DC
VS = 3.3V, 0V
6552 G13
140
1
6552 G12
CF
8pF
CF
8pF
0.1M
2
PHASE (DEG)
CLOSED-LOOP VOLTAGE GAIN (dB)
8
3
100k
Gain Flatness vs Frequency
AV = 2
VOUT = 1.5V DC
VS = 3.3V, 0V
9
4
6552 G11
6552 G10
10
VS = 5V, 0V
VCM = 1V
–3dB BANDWIDTH (MHz)
–100
175
OPEN-LOOP GAIN
0
5
VS = 5V, 0V
200 VCM = 1V
INPUT NOISE CURRENT DENSITY (pA/√Hz)
VS = ±5V
INPUT NOISE VOLTAGE DENSITY (nV/√Hz)
CHANGE IN INPUT OFFSET VOLTAGE (µV)
500
Input Noise Current Density vs
Frequency
VS = ±5V
75
70
65
60
55
–50 –25
VS = 3.3V, OV
VOUT = 1.5V
50
25
75
0
TEMPERATURE (°C)
100
125
6552 G18
6552f
8
LT6552
U W
TYPICAL PERFOR A CE CHARACTERISTICS
RL = 150Ω
TA = 25°C
VOUT = –3V TO 3V
VS = ±5V
Output Impedance vs Frequency
Slew Rate vs Temperature
550
VS = ±5V
AV = 2
RL = 150Ω
AV = 2
1
0.1
VS = 5V, 0V
VOUT = 0.5V T0 3.5V
400
10M
1M
FALLING
300
VS = 3.3V, 0V
VOUT = 0.5V T0 2.5V
RISING
100
VS = 3.3V, 0V
50
40
30
20
1M
10M
FREQUENCY (Hz)
60
NEGATIVE SUPPLY
40
30
POSITIVE SUPPLY
20
30
25
RS = 20Ω, RL = ∞
20
RS = RL = 50Ω
1M
10M
FREQUENCY (Hz)
100M
100
CAPACITIVE LOAD (pF)
10
6552 G23
–30
–40
RL = 150Ω, 2ND
6552 G24
VS = ±5V
AV = 2
VO = 2VP-P
–50
–60
–70
–80
RL = 1k, 2ND
RL = 150Ω, 2ND
RL = 150Ω, 3RD
RL = 1k, 2ND
–90
RL = 1k, 3RD
100k
1M
FREQUENCY (Hz)
1000
2nd and 3rd Harmonic Distortion
vs Frequency
–50
–80
10k
RS = 10Ω, RL = ∞
35
0
100k
RL = 150Ω, 3RD
–70
VS = 5V, 0V
50 A = 2
V
45 RF = RG = 500Ω
CFB = 8pF
40
5
0
10k
100M
10
55
10
VS = 3.3V, 0V
AV = 2
VO = 0.5V TO 2.5V
–60
8
15
10
2nd and 3rd Harmonic Distortion
vs Frequency
–40
6
GAIN (AV)
Series Output Resistor vs
Capacitive Load
50
6552 G22
–30
4
6552 G21
VS = ±5V
TA = 25°C
DISTORTION (dB)
10
100k
2
125
Power Supply Rejection Ratio vs
Frequency
POWER SUPPLY REJECTION RATIO (dB)
VS = ±5V
60
DISTORTION (dB)
COMMON MODE REJECTION RATIO (dB)
70
300
6552 G20
Common Mode Rejection Ratio vs
Frequency
80
RISING
400
200
6552 G19
VCM = 0V DC
500
0
50
25
75
0
TEMPERATURE (°C)
FREQUENCY (Hz)
90
FALLING
600
100
200
–50 –25
100M
RISING
350
250
0.01
100k
700
450
SLEW RATE (V/µs)
AV = 10
RL = 150Ω
TA = 25°C
VOUT = –3V TO 3V
VS = ±5V
800
FALLING
10
SLEW RATE (V/µs)
OUTPUT IMPEDANCE (Ω)
500
Slew Rate vs Closed-Loop Gain
900
OVERSHOOT (%)
100
RL = 1k, 3RD
10M
6552 G25
–100
10k
100k
1M
FREQUENCY (Hz)
10M
6552 G26
6552f
9
LT6552
U W
TYPICAL PERFOR A CE CHARACTERISTICS
Large Signal Response,
VS = 5V, 0V
0V
AV = 2
CF = 5pF
CL = 10pF
RF = RG = 500Ω
RL = 150Ω
50ns/DIV
Small Signal Response,
VS = 5V, 0V
50mV/DIV
1V/DIV
500mV/DIV
Large Signal Response,
VS = ±5V
0V
6552 G27
AV = 2
CF = 5pF
CL = 10pF
RF = RG = 500Ω
RL = 150Ω
Small Signal Response,
VS = 5V, 0V
50ns/DIV
6552 G28
AV = 1
CL = 10pF
RL = 150Ω
Shutdown Response
50ns/DIV
6552 G29
Output Overdrive Recovery
VSHDN
2V/DIV
50mV/DIV
2.5V
VIN
1V/DIV
0V
0V
2.5V
AV = 2
CF = 5pF
CL = 10pF
RF = RG = 500Ω
RL = 150Ω
50ns/DIV
6552 G30
VOUT
1V/DIV
VOUT
2V/DIV
0V
0V
AV = 2
RL = 150Ω
VIN = 1.25V
VS = 5V, 0V
200ns/DIV
6552 G31
AV = 2
VS = 5V, 0V
100ns/DIV
6552 G32
6552f
10
LT6552
U
U
W
U
APPLICATIO S I FOR ATIO
The LT6552 is a video difference amplifier with two pairs
of high impedance inputs. The primary purpose of the
LT6552 is to convert high frequency differential signals
into a single-ended output, while rejecting any common
mode noise. In the simplest configuration, one pair of
inputs is connected to the incoming differential signal,
while the other pair of inputs is used to set amplifier gain
and DC level. The device will operate on either single or
dual supplies and has an input common mode range
which includes the negative supply. The common mode
rejection ratio is greater than 60dB at 10MHz. Feedback is
applied to Pin 8 and the LT6552’s transient response is
optimized for gains of 2 or greater.
Figure 3 shows the single supply connection. The amplifier gain is set by a feedback network from the output to
Pin 8 (FB). A DC signal applied to Pin 1 (REF) establishes
the output quiescent voltage and the differential signal is
applied to Pins 2 and 3.
Figure 4 shows several other connections using dual
supplies. In each case, the amplifier gain is set by a
feedback network from the output to Pin 8 (FB).
SHDN
VINDIFF
VDC
5
3
2
V+
7
+
– LT6552
1
REF
8
FB
6
VO
4
RF
R + RG
VO = (VINDIFF + VDC) F
RG
RG
6552 F01
Figure 3
SHDN
VIN
3
2
5
SHDN
V+
+
– LT6552
7
1
REF
8
FB
RG
6
VO
4
VIN
3
2
5
SHDN
V+
+
– LT6552
7
1
REF
8
FB
VINDIFF
6
VO
VIN
4
RG
3
2
5
V+
7
+
– LT6552
1
REF
8
FB
V–
V–
RF
RF
RF
( R R+ R ( V
F
G
G
IN
RG
VO = –
( R R+ R ( V
F
G
G
IN
VO =
( R R+ R ( V
F
G
G
VO
4
V–
VO = +
6
INDIFF –
( RR ( V
F
G
IN
6552 F01
Figure 4
6552f
11
LT6552
U
W
U U
APPLICATIO S I FOR ATIO
Amplifier Characteristics
The current generated through R1 or R2, divided by the
capacitor CM, determines the slew rate. Note that this
current, and hence the slew rate, are proportional to the
magnitude of the input step. The input step equals the
output step divided by the closed-loop gain. The highest
slew rates are therefore obtained in the lowest gain configurations. The Typical Performance Characteristic Curve
of Slew Rate vs Closed-Loop Gain shows the details.
Figure 5 shows a simplified schematic of the LT6552.
There are two input stages; the first one consists of
transistors Q1 to Q8 for the (+) and (–) inputs while the
second input stage consists of transistors Q9 to Q16 for
the reference and feedback inputs. This topology provides
high slew rates at low supply voltages. The input common
mode range extends from ground to typically 1.75V from
VCC, and is limited by 2VBE’s plus a saturation voltage of
current sources I1-I4. Each input stage drives the degeneration resistors of PNP and NPN current mirrors, Q17 to
Q20, that convert the differential signals into a singleended output. The complementary drive generator supplies current to the output transistors that swing from railto-rail.
ESD
The LT6552 has reverse-biased ESD protection diodes on
all inputs and outputs, as shown in Figure 5. If these pins
are forced beyond either supply, unlimited current will
flow through these diodes. If the current is transient in
nature and limited to 100mA or less, no damage to the
device will occur.
7 V+
I1
I2
I3
I5
I4
R3
R4
Q21
Q17
Q2
Q3
Q5
R1
Q4
Q6
Q7
Q10
Q11 Q13
R2
Q18
Q15
CM
V+
DESD9
Q1
Q8
Q9
Q12 Q14
Q16
COMPLEMENTARY
DRIVE GENERATOR
6 OUT
DESD10
Q19
Q20
V–
Q22
I6
V+
RIN1
V+
DESD1
DESD2
3
+IN
V–
V+
RIN2
DESD3
RIN3
DESD6
V–
2
–IN
1
REF
V–
R6
4 V–
V+
V+
DESD5
DESD4
R5
V+
RIN4
DESD7
DESD11
5 SHDN
BIAS
DESD8
V–
8
FB
DESD12
V–
6552 FO5
Figure 5. Simplified Schematic
6552f
12
LT6552
U
W
U U
APPLICATIO S I FOR ATIO
Layout and Passive Components
Operating with Low Closed-Loop Gains
With a bandwidth of 75MHz and a slew rate of 600V/µs, the
LT6552 requires special attention to board layout and
supply bypassing. Use a ground plane, short lead lengths
and RF quality low ESR supply bypass capacitors. The
positive supply pin should be bypassed with a small
capacitor (typically 0.1µF) within 1 inch of the pin. When
driving loads greater than 10mA, an additional 4.7µF
electrolytic capacitor should be used. When using split
supplies, the same is true for the negative supply pin. The
parallel combination of the feedback resistor and gain
setting resistor on Pin 8 (FB) can combine with the input
capacitance to form a pole which can degrade stability. In
general, use feedback resistors of 1k or less.
The LT6552 has been optimized for closed-loop gains of
2 or greater. For a closed-loop gain of 2 the response
peaks about 3dB. Peaking can be reduced by using low
value feedback resistors, and can be eliminated by placing
a capacitor across the feedback resistor (feedback zero).
Figure 6 shows the closed-loop gain of 2 frequency
response with various values of the feedback capacitor.
This peaking shows up as a time domain overshoot of
40%; with an 8pF feedback capacitor the overshoot is
eliminated. Figures 7A and 7B show the Small Signal
Response of the LT6552 with and without an 8pF feedback
capacitor.
10
CLOSED-LOOP VOLTAGE GAIN (dB)
AV = 2
9 RF = RG = 500Ω
RL = 150Ω
8 T = 25°C
A
7 VOUT = 1.5V DC
VS = 3.3V, 0V
6
CF = 0pF
CF = 3pF
CF = 5pF
5
CF = 8pF
4
CF = 10pF
3
2
1
0
0.1
1
10
FREQUENCY (MHz)
100
6552 F06
50mV/DIV
50mV/DIV
Figure 6. Closed-Loop Gain vs Frequency
1.5V
AV = 2
RF = RG = 500Ω
RL = 150Ω
50ns/DIV
6552 F07a
Figure 7A. Small Signal Transient
Response, VS = 3.3V, 0V
1.5V
AV = 2
CF = 8pF
RF = RG = 500Ω
RL = 150Ω
50ns/DIV
6552 F07b
Figure 7B. Small Signal Transient Response,
VS = 3.3V, 0V with 8pF Feedback Capacitor
6552f
13
LT6552
U
W
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APPLICATIO S I FOR ATIO
SHDN Pin
The LT6552 includes a shutdown feature that disables the
part, reducing quiescent current and making the output
high impedance. The part can be shutdown by bringing the
SHDN pin within 0.5V of V–. When shutdown the supply
current is typically 400µA and the output leakage current
is 0.25µA (V– ≤ VOUT ≤ V+). In normal operation the SHDN
can be tied to V+ or left floating; if the pin is left unconnected, an internal FET pull-up will keep the LT6552 fully
operational.
U
PACKAGE DESCRIPTIO
DD Package
8-Lead Plastic DFN (3mm × 3mm)
(Reference LTC DWG # 05-08-1698)
0.675 ±0.05
3.5 ±0.05
1.65 ±0.05
2.15 ±0.05 (2 SIDES)
PACKAGE
OUTLINE
0.25 ± 0.05
0.50
BSC
2.38 ±0.05
(2 SIDES)
RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS
R = 0.115
TYP
5
3.00 ±0.10
(4 SIDES)
0.38 ± 0.10
8
1.65 ± 0.10
(2 SIDES)
PIN 1
TOP MARK
(NOTE 6)
(DD8) DFN 1203
0.200 REF
0.75 ±0.05
0.00 – 0.05
4
0.25 ± 0.05
1
0.50 BSC
2.38 ±0.10
(2 SIDES)
BOTTOM VIEW—EXPOSED PAD
NOTE:
1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1)
2. DRAWING NOT TO SCALE
3. ALL DIMENSIONS ARE IN MILLIMETERS
4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE
MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE
5. EXPOSED PAD SHALL BE SOLDER PLATED
6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION
ON TOP AND BOTTOM OF PACKAGE
6552f
14
LT6552
U
PACKAGE DESCRIPTIO
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
NOTE 3
.045 ±.005
.050 BSC
8
.245
MIN
7
6
5
.160 ±.005
.150 – .157
(3.810 – 3.988)
NOTE 3
.228 – .244
(5.791 – 6.197)
.030 ±.005
TYP
1
RECOMMENDED SOLDER PAD LAYOUT
.010 – .020
× 45°
(0.254 – 0.508)
.008 – .010
(0.203 – 0.254)
3
4
.053 – .069
(1.346 – 1.752)
.004 – .010
(0.101 – 0.254)
0°– 8° TYP
.016 – .050
(0.406 – 1.270)
NOTE:
1. DIMENSIONS IN
2
.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
SO8 0303
6552f
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.
15
LT6552
U
TYPICAL APPLICATIO
YPBPR to RGB Video Converter
+3V
+3V
499Ω
499Ω
499Ω
499Ω
5.6pF
8.2pF
8
8
1
2
3
FB
7
REF
–
+
1
LT6552
6
2
3
5
4
FB
7
REF
–
+
LT6552
6
75Ω
G
5
4
75Ω
SD
SD
–3V
–3V
+3V
499Ω
909Ω
Y
2.2pF
8
1
PR
21.5Ω
53.6Ω
2
21.5Ω
3
FB
7
REF
–
+
11.3Ω
LT6552
6
75Ω
R
5
4
75Ω
SD
–3V
+3V
42.2Ω
499Ω
1.3k
1pF
8
1
PB
2
49.9Ω
25.5Ω
3
FB
7
REF
–
+
LT6552
6
75Ω
B
5
4
75Ω
SD
–3V
R = Y + 1.4 • PR
G = Y – 0.34 • PB – 0.71 • PR
B = Y + 1.8 • PB
BW (± 0.5dB) > 25MHz
BW (–3dB) > 36MHz
IS ≈ 70mA
6552 TA02
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1193
AV = 2 Video Difference Amp
80MHz BW, 500V/µs Slew Rate, Shutdown
LT1675
RGB Multiplexer with Current Feedback Amplifiers
–3dB Bandwidth = 250MHz, 100MHz Pixel Switching
LT6205/LT6206/LT6207
Single/Dual/Quad Single Supply
3V, 100MHz Video Op Amps
450V/µs Slew Rate, Rail-to-Rail Output,
Input Common Modes to Ground
LT6550/LT6551
3.3V Triple and Quad Video Amplifiers
Internal Gain of 2, 110MHz –3dB Bandwidth,
Input Common Modes to Ground
6552f
16
Linear Technology Corporation
LT/TP 0304 1K • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
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 LINEAR TECHNOLOGY CORPORATION 2003