LT1567
1.4nV/√Hz 180MHz
Filter Building Block
FEATURES
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DESCRIPTIO
Single-Ended to Differential Conversion
Low Noise: 1.4nV/√Hz
20µV
RMS
Total Wideband Noise in Filter
with 2MHz f
C
Dynamic Range: 104dB SNR at
±5V
Total Supply Voltage: 2.7V to 12V
Rail-to-Rail Outputs
DC Accurate: Op Amp V
OS
0.5mV (Typ)
Trimmed Bandwidth for Accurate Filters
No External Clock Required
MSOP-8 Surface Mount Package
The LT
®
1567 is an analog building block optimized for
very low noise high frequency filter applications. It con-
tains two wideband rail-to-rail operational amplifiers, one
of them internally configured as a unity-gain inverter.
With the addition of a few passive components, the
LT1567 becomes a flexible second order filter section
with cutoff frequency (f
C
) up to 5MHz, ideal for antialias-
ing or for channel filtering in high speed data communi-
cations systems. A spreadsheet-based design tool is
available at www.linear.com for designing lowpass and
bandpass filters using the LT1567.
In addition to low noise and high speed, the LT1567
features single-ended to differential conversion for direct
driving of high speed differential input A/D converters. The
LT1567 operates from a total power supply voltage of 2.7V
to 12V and supports signal-to-noise ratios above 100dB.
The LT1567 is available in an 8-lead MSOP package.
, LTC, LT and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
APPLICATIO S
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Low Noise, High Speed Filters to 5MHz
Low Noise Differential Circuits
Communication Channel or Roofing Filters
Antialias or Reconstruction Filtering
Video Signal Processing
Single-Ended to Differential Conversion
TYPICAL APPLICATIO
2MHz 3-Pole Antialias Filter with
Single-Ended to Differential Conversion
R2
536Ω
R1
536Ω
V
IN
C1
270pF
0.1µF
3
4
0.1µF
V
96dB DIFFERENTIAL SNR WITH 3V TOTAL SUPPLY
GAIN = R2
≤
2.5MHz
R1
f
–3dB
R3 = R4 = R5, C1 = C2 = C3
1 ; f
≤
2.5MHz
f
–3dB
= 1.82 =
2πR2C2 4πR3C3
–3dB
–
V
+
0.1µF
C2
270pF
1
2
LT1567
8
7
6
5
C3
270pF
R5
147Ω
1567 TA01
12
6
R3
147Ω
R4
147Ω
+A
IN
ADC
–A
IN
LTC1420
0
GAIN (dB)
–6
–12
–18
–24
NOTE: 6dB GAIN RESULTS FROM
–30 SINGLE-ENDED TO DIFFERENTIAL
CONVERSION
–36
100
1M
FREQUENCY (Hz)
U
Frequency Response
10M
1567 TA01a
U
U
1567fa
1
LT1567
ABSOLUTE
(Note 1)
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
OAOUT
OAIN
BYPASS
V
–
1
2
3
4
8
7
6
5
V
+
INVOUT
INVIN
DC BIAS
Total Supply Voltage (V
+
to V
–
) ............................ 12.6V
Input Current (Note 2) ........................................
±25mA
Operating Temperature Range (Note 3)
LT1567C ..............................................–40°C to 85°C
LT1567I ...............................................–40°C to 85°C
Specified Temperature Range (Note 4)
LT1567C ..............................................–40°C to 85°C
LT1567I ...............................................–40°C to 85°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LT1567CMS8
LT1567IMS8
MS8 PART MARKING
LTWH
LTWJ
MS8 PACKAGE
8-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 200°C/W
Order Options
Tape and Reel: Add #TR
Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking:
http://www.linear.com/leadfree/
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
The
●
denotes the specifications that apply over the full operating temperature range (Note 4), otherwise specifications and typical
values are at T
A
= 25°C. V
S
=
±2.5V,
R
L
= 1K, V
OUT
= 0 on both amplifiers unless otherwise noted.
PARAMETER
Total Supply Voltage
Supply Current
V
S
=
±1.5V
V
S
=
±2.5V
V
S
=
±5V
V
S
=
±1.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
=100
V
S
=
±5V,
R
L
= 1k
V
S
=
±1.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
=100
V
S
=
±5V,
R
L
= 1k
V
S
=
±1.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 100 (LT1567I Only, Note 5)
V
S
=
±5V,
R
L
= 1k
V
S
=
±1.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 1k
V
S
=
±2.5V,
R
L
= 100 (LT1567I Only, Note 5)
V
S
=
±5V,
R
L
= 1k
V
S
=
±1.5V,
CMRR
≥
40dB (Note 6)
V
S
=
±5V,
CMRR
≥
40dB (Note 6)
V
S
=
±1.5V,
DC BIAS = –0.25V to 0.25V
V
S
=
±5V,
DC BIAS = –2.5V to 2.5V
V
S
=
±1.5V
to
±5V,
DC BIAS = 0V
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
CONDITIONS
MIN
2.7
TYP
8.5
9
11
MAX
12
15
16
19
UNITS
V
mA
mA
mA
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
OA Output Positive Voltage Swing
1.30
2.20
1.90
4.70
–1.30
–2.20
–2.00
–4.70
1.30
2.20
1.80
4.60
–1.30
–2.20
–1.80
–4.50
–0.5
–3.8
80
65
80
1.45
2.45
2.25
4.90
–1.45
–2.45
–2.30
–4.90
1.40
2.50
2.00
4.80
–1.40
–2.40
–2.00
–4.80
0.5
3.5
90
100
0.5
5
3
9
OA Output Negative Voltage Swing
INV Output Positive Voltage Swing
INV Output Negative Voltage Swing
Common Mode Input Voltage Range (DC BIAS, Pin 5)
(See Pin Functions)
DC Common Mode Rejection Ratio (CMRR)
DC Power Supply Rejection Ratio (PSRR)
OA Input Offset Voltage
INV Output Offset Voltage
2
U
V
V
dB
dB
dB
mV
mV
1567fa
W
U
U
W W
W
LT1567
ELECTRICAL CHARACTERISTICS
The
●
denotes the specifications that apply over the full operating temperature range (Note 4), otherwise specifications and typical
values are at T
A
= 25°C. V
S
=
±2.5V,
R
L
= 1K, V
OUT
= 0 on both amplifiers unless otherwise noted.
PARAMETER
OA Input Bias Current
DC BIAS Input Bias Current
OA DC Open-Loop Gain
V
S
=
±1.5V,
R
L
= 1k, V
O
= –1V to 1V
V
S
=
±2.5V,
R
L
= 1k, V
O
= –2V to 2V
V
S
=
±2.5V,
R
L
= 100, V
O
= –1.5V to 1.5V
V
S
=
±5V,
R
L
= 1k, V
O
= –4V to 4V
V
S
=
±1.5V,
R
L
= 1k, V
IN
= –1V to 1V
V
S
=
±2.5V,
R
L
= 1k, V
IN
= –2V to 2V
V
S
=
±2.5V,
R
L
= 100, V
IN
= –1.5V to 1.5V
V
S
=
±5V,
R
L
= 1k, V
IN
= –4V to 4V
V
S
=
±2.5V,
R
L
= 1k, V
IN
= –2V to 2V
Measured at 2MHz, V
S
=
±1.5V
Measured at 2MHz, V
S
=
±2.5V
Measured at 2MHz, V
S
=
±5V
–3dB
Measured at 2MHz
V
S
=
±5V
V
S
=
±5V
f = 100kHz
f = 100kHz
f
C
= 2MHz, BW = 4MHz (Note 8)
f
C
= 5MHz, BW = 10MHz (Note 8)
f = 1MHz, f
C
= 2MHz, V
OUT
= 1V
RMS
f = 2.5MHz, f
C
= 5MHz, V
OUT
= 1V
RMS
●
●
CONDITIONS
●
●
●
●
●
●
●
●
●
●
●
●
●
●
MIN
TYP
3
6
MAX
10
15
UNITS
µA
µA
V/mV
V/mV
V/mV
V/mV
7.5
10
1.2
10
0.97
0.97
0.97
0.97
450
100
110
120
0.96
55
60
7.0
80
1.04
1.04
1.04
1.04
600
180
185
190
85
1.0
55
90
1.4
1.0
20
30
–88
–70
1.05
750
INV DC Gain
V/V
V/V
V/V
V/V
Ω
MHz
MHz
MHz
MHz
V/V
V/µs
V/µs
nV/√Hz
pA/√Hz
µV
RMS
µV
RMS
dB
dB
mA
Ω
Ω
INV DC Input Resistance
OA Gain Bandwidth Product
INV Bandwidth
INV AC Gain
OA Slew Rate
INV Slew Rate
OA Input Voltage Noise Density (Note 7)
OA Input Current Noise Density
Wideband Output Noise for a Second Order Filter (Figure 1)
Total Harmonic Distortion (THD)
for a Second Order Filter (Figure 1)
Output Short-Circuit Current (Note 9)
OA Output Impedance
INV Output Impedance
8
50
0.03
0.7
f = 100kHz, OA Connected as
Unity-Gain Inverter
f = 100kHz
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
The inputs of each op amp are protected by back-to-back diodes
and diodes to each supply. If either input exceeds the supply or the
differential input voltage exceeds 1.4V, the input current should be limited
to less than 25mA.
Note 3:
The LT1567C and LT1567I are guaranteed functional over the
operating temperature range –40°C to 85°C.
Note 4:
The LT1567C is guaranteed to meet specified performance from
0°C to 70°C. The LT1567C is designed, characterized and expected to
meet specified performance from –40°C to 85°C but not tested or QA
sampled at these temperatures. The LT1567I is guaranteed to meet
specified performance from – 40°C to 85°C.
Note 5:
With INVIN pin driven to
±2V.
Note 6:
This parameter is not 100% tested.
Note 7:
The input referred voltage noise density of the unity gain inverter
is 5.6nV/√Hz which includes the noise of the gain setting resistors.
Note 8:
For f
C
= 2MHz, C1 = C2 = 180pF, R1 = R2 = 604Ω, R3 = 316Ω and
for f
C
= 5MHz, C1 = C2 = 180pF, R1 = R2 = 232Ω, R1 = 130Ω. BW is the
bandwidth of the noise measurement (Figure 1 circuit).
Note 9:
Under direct short circuit conditions, with T
A
< 25°C the output
current is reduced.
1567fa
3
LT1567
TYPICAL PERFOR A CE CHARACTERISTICS
OA Open-Loop Gain and Phase
vs Frequency
70
60
50
40
GAIN (dB)
GAIN (dB)
30
20
10
0
–10
–20
–30
0.1
10
1
FREQUENCY (MHz)
100
1567 G01
Closed-Loop Gain and Phase of OA
and INV vs Frequency (A
V
= –1)
10
8
6
4
182
V
S
=
±5V
T
A
= 25°C 180
GAIN
OA OUT
178
GAIN
INV OUT
176
10
8
6
4
GAIN (dB)
GAIN (dB)
2
0
–2
–4
–6
–8
–10
0.1
1
10
FREQUENCY (MHz)
100
1567 G03
OA Gain Bandwidth Product and
Phase Margin vs Temperature
275
PHASE MARGIN
V
S
=
±5V
65
POWER SUPPLY REJECTION (dB)
250
GAIN BANDWIDTH (MHz)
45
PHASE MARGIN (DEG)
70
60
50
40
30
20
10
NEGATIVE
SUPPLY
V
S
=
±5V
A
V
= –10
R
F
= 1k
R
G
= 100Ω
R
L
= 1k
0.1
1
0.01
FREQUENCY (MHz)
10
1567 G04
POWER SUPPLY REJECTION (dB)
225
PHASE MARGIN
V
S
=
±1.5V
GBW PRODUCT
V
S
=
±5V
GBW PRODUCT
V
S
=
±1.5V
200
175
150
–55 –35 –15
–35
5 25 45 65 85 105 125
TEMPERATURE (°C)
1567 G14
4
U W
PHASE
INV OUT
5
OA Open-Loop Gain and Phase
vs Frequency
70
60
50
40
PHASE (DEG)
150
V
S
=
±5V
T
A
= 25°C 120
90
PHASE
60
30
GAIN
0
–30
–60
–90
–120
–150
150
V
S
=
±1.5V
T
A
= 25°C 120
90
PHASE
60
PHASE (DEG)
30
20
10
0
–10
–20
–30
0.1
1
10
FREQUENCY (MHz)
100
1567 G02
30
GAIN
0
–30
–60
–90
–120
–150
Closed-Loop Gain and Phase of OA
and INV vs Frequency (A
V
= –1)
182
GAIN
OA OUT
GAIN
180
INV OUT
178
176
PHASE (DEG)
PHASE (DEG)
174
172
PHASE
OA OUT
170
168
166
164
162
2
0
–2
–4
–6
–8
V
S
=
±1.5V
T
A
= 25°C
1
10
FREQUENCY (MHz)
100
1567 G15
174
172
PHASE
INV OUT
PHASE
OA OUT
170
168
166
164
162
–10
0.1
PSRR of OA vs Frequency
90
80
90
80
70
60
50
40
30
20
10
PSRR of OA or INV vs Frequency
POSITIVE
SUPPLY
25
POSITIVE
SUPPLY
NEGATIVE
SUPPLY
–15
0
0.001
0
0.001
V
S
=
±5V
A
V
= –1
R
F
= R
G
= 1k
R
L
= 1k
0.01
0.1
1
FREQUENCY (MHz)
10
1567 G05
1567fa
LT1567
TYPICAL PERFOR A CE CHARACTERISTICS
Output Impedance vs Frequency
100
V
S
=
±5V
T
A
= 25°C
OA
A
V
= –10
SLEW RATE (V/µs)
10
OUTPUT IMPEDANCE (Ω)
1
INVERTER
OA
A
V
= –1
40
V
S
=
±1.5V
30
OVERSHOOT (%)
0.1
0.01
0.001
100k
1M
10M
FREQUENCY (Hz)
Output Overshoot vs Series
Resistor and Capacitive Load
40
35
30
OVERSHOOT (%)
25
20
15
10
5
0
10
100
CAPACITIVE LOAD (pF)
1000
1567 G09
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
0.1
1
10
FREQUENCY (kHz)
100
1567 G10
CURRENT NOISE DENSITY (pA/√Hz)
VOLTAGE NOISE DENSITY (nV/√Hz)
V
S
=
±1.5V
A
V
= –1
R
S
= 10Ω
R
L
=
∞
R
S
= 20Ω
R
L
=
∞
R
S
= R
L
= 50Ω
Input Bias Current of OA
vs Common Mode Voltage
8
7
INPUT BIAS CURRENT (µA)
SUPPLY CURRENT (mA)
6
5
4
3
2
1
0
0
4
3
COMMON MODE VOLTAGE (V)
1567 G12
V
S
= 5V
1
U W
100M
1567 G06
OA Rising Slew Rate
vs Temperature
60
A
V
= –1
R
F
= R
G
= 1k
R
L
= 1k
30
V
S
=
±5V
25
20
15
10
5
20
–55 –35 –15
0
5 25 45 65 85 105 125
TEMPERATURE (°C)
1567 G07
Output Overshoot vs Series
Resistor and Capacitive Load
V
S
=
±2.5V
A
V
= –1
R
S
= 10Ω
R
L
=
∞
50
V
S
=
±2.5V
R
S
= 20Ω
R
L
=
∞
R
L
= R
S
= 50Ω
10
100
CAPACITIVE LOAD (pF)
1000
1567 G08
Input Voltage Noise Density of OA
vs Frequency
4.5
4.0
T
A
= 25°C
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
Input Current Noise Density of OA
vs Frequency
T
A
= 25°C
0
0.1
1
10
FREQUENCY (kHz)
100
1567 G11
Supply Current vs Supply Voltage
20
15
10
5
2
5
0
0
2
6
8
4
TOTAL SUPPLY VOLTAGE (V)
10
1567 G13
1567fa
5