LTC6911-1/LTC6911-2
Dual Matched Amplifiers
with Digitally Programmable
Gain in MSOP
FEATURES
s
DESCRIPTIO
s
s
s
s
s
s
s
s
s
s
3-Bit Digital Gain Control:
(Inverting Gains of 0, 1, 2, 5, 10, 20, 50
and 100V/V) -1 Option
(Inverting Gains of 0, 1, 2, 4, 8, 16, 32
and 64V/V) -2 Option
Two Matched Programmable Gain Amplifiers
Channel-to-Channel Gain Matching of 0.1dB (Max)
Rail-to-Rail Input Range
Rail-to-Rail Output Swing
Single or Dual Supply: 2.7V to 10.5V Total
11MHz Gain Bandwidth Product
Input Noise: 10nV/√Hz
Total System Dynamic Range to 120dB
Input Offset Voltage: 2mV, Gain of 10
Low Profile 10-Lead MSOP Package
The LTC
®
6911 is a family of low noise digitally program-
mable gain amplifiers (PGAs) that are easy to use and
occupy very little PC board space. The matched gain of
both channels is adjustable using a 3-bit parallel interface
to select voltage gains of 0, 1, 2, 5, 10, 20, 50 and 100V/
V (LTC6911-1) and 0, 1, 2, 4, 8, 16, 32 and 64V/V
(LTC6911-2). All gains are inverting.
The LTC6911 family consists of two matched inverting
amplifiers with rail-to-rail outputs. When operated with
unity gain, they will also process rail-to-rail input signals.
A half-supply reference generated internally at the AGND
pin supports single power supply applications. Operating
from single or split supplies from 2.7V to 10.5V, the
LTC6911 family is offered in a 10-lead MSOP package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIO S
s
s
s
s
Data Acquisition Systems
Dynamic Gain Changing
Automatic Ranging Circuits
Automatic Gain Control
TYPICAL APPLICATIO
V
+
2.7V TO 10.5V
7
0.1µF
9
DIGITAL
INPUT
GAIN IN V/V
G2 G1 G0 LTC6911-1 LTC6911-2
0 0 0
0
0
0 0 1
–1
–1
0 1 0
–2
–2
0 1 1
–5
–4
1 0 0
–10
–8
1 0 1
–20
–16
1 1 0
–50
–32
1 1 1
–100
–64
V
INA
AGND
≥1µF
1
10
V
OUTA
=
GAIN • V
INA
GAIN (dB)
2
LTC6911-X
V
INB
3
8
V
OUTB
=
GAIN • V
INB
691112 TA01
–10
100
4
G0
5
G1
6
G2
U
Frequency Response (LTC6911-1)
50
40
V
S
= 10V, V
IN
= 5mV
RMS
GAIN OF –100 (DIGITAL INPUT 111)
30 GAIN OF –50 (DIGITAL INPUT 110)
GAIN OF –20 (DIGITAL INPUT 101)
20
GAIN OF –10 (DIGITAL INPUT 100)
10 GAIN OF –5 (DIGITAL INPUT 011)
GAIN OF –2 (DIGITAL INPUT 010)
0
GAIN OF –1 (DIGITAL INPUT 001)
1k
10k
100k
FREQUENCY (Hz)
1M
10M
691112 TA02
U
U
sn691112 691112fs
1
LTC6911-1/LTC6911-2
ABSOLUTE
(Note 1)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
INA
AGND
INB
G0
G1
1
2
3
4
5
10
9
8
7
6
OUTA
V
–
OUTB
V
+
G2
Total Supply Voltage (V
+
to V
–
) .............................. 11V
Input Current .....................................................
±10mA
Operating Temperature Range (Note 2)
LTC6911C-1/LTC6911C-2 .................. – 40°C to 85°C
LTC6911I-1/LTC6911I-2 .................... – 40°C to 85°C
LTC6911H-1/LTC6911H-2 ................ – 40°C to 125°C
Specified Temperature Range (Note 3)
LTC6911C-1/LTC6911C-2 .................. – 40°C to 85°C
LTC6911I-1/LTC6911I-2 .................... – 40°C to 85°C
LTC6911H-1/LTC6911H-2 ................ – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
MS PACKAGE
10-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JA
= 230°C/W
ORDER PART NUMBER
LTC6911CMS-1
LTC6911IMS-1
LTC6911HMS-1
LTC6911CMS-2
LTC6911IMS-2
LTC6911HMS-2
MS PART MARKING
LTAHK
LTAHM
LTBCF
LTAHH
LTAHJ
LTBCG
Consult LTC Marketing for parts specified with wider operating temperature ranges.
GAI SETTI GS A D PROPERTIES
Table 1 (LTC6911-1)
NOMINAL
VOLTAGE GAIN
Volts/Volt
(dB)
0
–120
–1
0
–2
6
–5
14
–10
20
–20
26
–50
34
–100
40
MAXIMUM LINEAR INPUT RANGE (V
P-P
)
Dual 5V
Single 5V
Single 3V
Supply
Supply
Supply
10
5
3
10
5
3
5
2.5
1.5
2
1
0.6
1
0.5
0.3
0.5
0.25
0.15
0.2
0.1
0.06
0.1
0.05
0.03
NOMINAL
INPUT
IMPEDANCE
(kΩ)
(Open)
10
5
2
1
1
1
1
DIGITAL INPUTS
G2
G1
G0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
Table 2 (LTC6911-2)
DIGITAL INPUTS
G2
G1
G0
0
0
0
0
0
1
0
1
0
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
NOMINAL
VOLTAGE GAIN
Volts/Volt
(dB)
0
–120
–1
0
–2
6
–4
12
–8
18.1
–16
24.1
–32
30.1
–64
36.1
MAXIMUM LINEAR INPUT RANGE (V
P-P
)
Dual 5V
Single 5V
Single 3V
Supply
Supply
Supply
10
5
3
10
5
3
5
2.5
1.5
2.5
1.25
0.75
1.25
0.625
0.375
0.625
0.3125
0.188
0.3125
0.156
0.094
0.156
0.078
0.047
NOMINAL
INPUT
IMPEDANCE
(kΩ)
(Open)
10
5
2.5
1.25
1.25
1.25
1.25
sn691112 691112fs
2
U
W
U
U
W W
U
W
U
U
LTC6911-1/LTC6911-2
ELECTRICAL CHARACTERISTICS
PARAMETER
LTC6911-1/LTC6911-2
Total Supply Voltage (V
S
)
Supply Current per Channel
CONDITIONS
The
q
denotes the specifications that apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
S
= 5V, AGND = 2.5V, Gain = 1 (Digital Inputs 001), R
L
= 10k
to midsupply point, unless otherwise noted.
C/I GRADES
MIN TYP MAX
q
H GRADE
MIN TYP MAX
2.7
2.1
2.5
3.1
3.1
12
60
20
100
30
190
10
50
10
90
20
180
±27
±35
10.5
3.25
4.00
5.00
5.00
35
125
45
190
60
290
25
90
35
175
45
270
UNITS
V
mA
mA
mA
mA
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mA
mA
2.7
2.1
2.5
3.1
3.1
12
60
20
100
30
190
10
50
10
90
20
180
±27
±35
2.45
0.55
0.75
– 4.30
55
55
60
80
75
80
12
16
2.5
10.5
3.15
3.75
4.65
4.65
30
110
40
170
50
260
20
80
30
160
40
250
V
S
= 2.7V, V
INA
= V
INB
= V
AGND
V
S
= 5V, V
INA
= V
INB
= V
AGND
V
S
=
±5V,
V
INA
= V
INB
= 0V, Pins 4, 5, 6 = –4.5V or 5V
V
S
=
±5V,
V
INA
= V
INB
= 0V, Pin 4 = 4.5V,
Pins 5, 6 = 0.5V
V
S
= 2.7V, R
L
= 10k Tied to Mid Supply
V
S
= 2.7V, R
L
= 500Ω Tied to Mid Supply
V
S
= 5V, R
L
= 10k Tied to Mid Supply
V
S
= 5V, R
L
= 500Ω Tied to Mid Supply
V
S
=
±5V,
R
L
= 10k Tied to 0V
V
S
=
±5V,
R
L
= 500Ω Tied to 0V
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
Output Voltage Swing LOW (Note 4)
Output Voltage Swing HIGH (Note 4)
V
S
= 2.7V, R
L
= 10k Tied to Mid Supply
V
S
= 2.7V, R
L
= 500Ω Tied to Mid Supply
V
S
= 5V, R
L
= 10k Tied to Mid Supply
V
S
= 5V, R
L
= 500Ω Tied to Mid Supply
V
S
=
±5V,
R
L
= 10k Tied to 0V
V
S
=
±5V,
R
L
= 500Ω Tied to 0V
Output Short-Circuit Current (Note 5)
AGND Open-Circuit Voltage
AGND (Common Mode)
Input Voltage Range
AGND Rejection (i.e., Common
Mode Rejection or CMRR)
Power Supply Rejection Ratio (PSRR)
Slew Rate
Signal Attenuation at Gain = 0 Setting
Digital Input “High” Voltage
V
S
= 2.7V
V
S
=
±5V
V
S
= 5V
V
S
= 2.7V
V
S
= 5V
V
S
=
±5V
V
S
= 2.7V, V
AGND
= 1.1V to 1.6V
V
S
=
±5V,
V
AGND
= – 2.5V to 2.5V
V
S
= 2.7V to
±5V
V
S
= 5V, V
OUTA
= V
OUTB
= 1.1V to 3.9V
V
S
=
±5V,
V
OUTA
= V
OUTB
=
±1.4V
Gain = 0 (Digital Inputs 000), f = 20kHz
V
S
= 2.7V
V
S
= 5V
V
S
=
±5V
V
S
= 2.7V
V
S
= 5V
V
S
=
±5V
V
S
= 2.7V, Pins 4, 5, 6 = 2.43V
V
S
= 5V, Pins 4, 5, 6 = 4.5V
V
S
=
±5V,
Pins 4, 5, 6 = 4.5V
V
S
= 2.7V, Pins 4, 5, 6 = 0.27V
V
S
= 5V, Pins 4, 5, 6 = 0.5V
V
S
=
±5V,
Pins 4, 5, 6 = 0.5V
2.55
1.60
3.65
3.20
2.45
0.55
0.75
– 4.30
50
50
57
2.5
2.55
1.60
3.65
3.20
V
V
V
V
dB
dB
dB
V/µs
V/µs
dB
V
V
V
80
75
80
12
16
– 120
q
q
q
q
q
q
q
q
q
q
q
q
q
– 120
2.43
4.50
4.50
0.27
0.50
0.50
1
5
10
1
5
10
2.43
4.50
4.50
Digital Input “Low” Voltage
0.27
0.50
0.50
1
5
10
1
5
10
V
V
V
µA
µA
µA
µA
µA
µA
Digital Input “High” Current
Digital Input “Low” Current
sn691112 691112fs
3
LTC6911-1/LTC6911-2
ELECTRICAL CHARACTERISTICS
PARAMETER
LTC6911-1 Only
Voltage Gain (Note 6)
CONDITIONS
The
q
denotes the specifications that apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
S
= 5V, AGND = 2.5V, Gain = 1 (Digital Inputs 001), R
L
= 10k
to midsupply point, unless otherwise noted.
C/I GRADES
MIN TYP MAX
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
H GRADE
MIN TYP MAX
–0.08 0
0.07
–0.13 –0.02 0.07
5.93
6.01
6.08
13.8 13.95 14.05
19.65 19.93 20.1
19.45 19.85 20.1
25.65 25.94 26.1
33.4
38.8
36.5
33.8
39.6
38.9
34.1
40.1
40.1
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
V
S
= 2.7V, Gain = 1, R
L
= 10k
V
S
= 2.7V, Gain = 1, R
L
= 500Ω
V
S
= 2.7V, Gain = 2, R
L
= 10k
V
S
= 2.7V, Gain = 5, R
L
= 10k
V
S
= 2.7V, Gain = 10, R
L
= 10k
V
S
= 2.7V, Gain = 10, R
L
= 500Ω
V
S
= 2.7V, Gain = 20, R
L
= 10k
V
S
= 2.7V, Gain = 50, R
L
= 10k
V
S
= 2.7V, Gain = 100, R
L
= 10k
V
S
= 2.7V, Gain = 100, R
L
= 500Ω
V
S
= 5V, Gain = 1, R
L
= 10k
V
S
= 5V, Gain = 1, R
L
= 500Ω
V
S
= 5V, Gain = 2, R
L
= 10k
V
S
= 5V, Gain = 5, R
L
= 10k
V
S
= 5V, Gain = 10, R
L
= 10k
V
S
= 5V, Gain = 10, R
L
= 500Ω
V
S
= 5V, Gain = 20, R
L
= 10k
V
S
= 5V, Gain = 50, R
L
= 10k
V
S
= 5V, Gain = 100, R
L
= 10k
V
S
= 5V, Gain = 100, R
L
= 500Ω
V
S
=
±5V,
Gain = 1, R
L
= 10k
V
S
=
±5V,
Gain = 1, R
L
= 500Ω
V
S
=
±5V,
Gain = 2, R
L
= 10k
V
S
=
±5V,
Gain = 5, R
L
= 10k
V
S
=
±5V,
Gain = 10, R
L
= 10k
V
S
=
±5V,
Gain = 10, R
L
= 500Ω
V
S
=
±5V,
Gain = 20, R
L
= 10k
V
S
=
±5V,
Gain = 50, R
L
= 10k
V
S
=
±5V,
Gain = 100, R
L
= 10k
V
S
=
±5V,
Gain = 100, R
L
= 500Ω
–0.07 0
0.07
–0.11 –0.02 0.07
5.94 6.01
6.08
13.85 13.95 14.05
19.7 19.93 20.1
19.6 19.85 20.1
25.75 25.94 26.1
33.5 33.8
39.0 39.6
37.4 38.9
34.1
40.1
40.1
–0.08 0.01 0.08
–0.11 –0.01 0.07
5.95 6.02
6.09
13.8 13.96 14.1
19.8 19.94 20.1
19.6 19.87 20.1
25.8 25.94 26.1
33.5 33.84 34.1
39.3 39.7
38.0 39.2
–0.06 0.01
–0.10 0.00
5.95 6.02
40.1
40.1
0.08
0.08
6.09
–0.09 0.01 0.08
–0.13 –0.01 0.07
5.94
6.02
6.09
13.78 13.96 14.1
19.75 19.94 20.1
19.45 19.87 20.1
25.75 25.94 26.1
33.4 33.84 34.1
39.1
37.0
39.7
39.2
40.1
40.1
0.08
0.08
6.09
–0.07 0.01
–0.11 0.00
5.94
6.02
13.8 13.96 14.1
19.8 19.94 20.1
19.7 19.91 20.1
25.8 25.95 26.1
33.7 33.87 34.1
39.4 39.8
38.8 39.5
–0.1 0.02
–0.1 0.02
–0.1 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.20 0.02
–1.00 0.02
40.2
40.1
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.20
1.00
13.79 13.96 14.1
19.75 19.94 20.1
19.60 19.91 20.1
25.75 25.95 26.1
33.60 33.87 34.1
39.25 39.8
38.00 39.5
–0.1
–0.1
–0.1
0.02
0.02
0.02
40.2
40.1
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.20
1.50
Channel-to-Channel Voltage
Gain Match
V
S
= 2.7V, Gain = 1, R
L
= 10k
V
S
= 2.7V, Gain = 1, R
L
= 500Ω
V
S
= 2.7V, Gain = 2, R
L
= 10k
V
S
= 2.7V, Gain = 5, R
L
= 10k
V
S
= 2.7V, Gain = 10, R
L
= 10k
V
S
= 2.7V, Gain = 10, R
L
= 500Ω
V
S
= 2.7V, Gain = 20, R
L
= 10k
V
S
= 2.7V, Gain = 50, R
L
= 10k
V
S
= 2.7V, Gain = 100, R
L
= 10k
V
S
= 2.7V, Gain = 100, R
L
= 500Ω
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.20 0.02
–1.50 0.02
sn691112 691112fs
4
LTC6911-1/LTC6911-2
ELECTRICAL CHARACTERISTICS
PARAMETER
LTC6911-1 Only
Channel-to-Channel Voltage
Gain Match
CONDITIONS
The
q
denotes the specifications that apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
S
= 5V, AGND = 2.5V, Gain = 1 (Digital Inputs 001), R
L
= 10k
to midsupply point, unless otherwise noted.
C/I GRADES
MIN TYP MAX
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
H GRADE
MIN TYP MAX
–0.1
–0.1
–0.1
0.02
0.02
0.02
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.2
1.2
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.2
0.9
UNITS
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
dB
ppm/°C
ppm/°C-
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
ppm/°C
dB
dB
dB
V
S
= 5V, Gain = 1, R
L
= 10k
V
S
= 5V, Gain = 1, R
L
= 500Ω
V
S
= 5V, Gain = 2, R
L
= 10k
V
S
= 5V, Gain = 5, R
L
= 10k
V
S
= 5V, Gain = 10, R
L
= 10k
V
S
= 5V, Gain = 10, R
L
= 500Ω
V
S
= 5V, Gain = 20, R
L
= 10k
V
S
= 5V, Gain = 50, R
L
= 10k
V
S
= 5V, Gain = 100, R
L
= 10k
V
S
= 5V, Gain = 100, R
L
= 500Ω
V
S
=
±5V,
Gain = 1, R
L
= 10k
V
S
=
±5V,
Gain = 1, R
L
= 500Ω
V
S
=
±5V,
Gain = 2, R
L
= 10k
V
S
=
±5V,
Gain = 5, R
L
= 10k
V
S
=
±5V,
Gain = 10, R
L
= 10k
V
S
=
±5V,
Gain = 10, R
L
= 500Ω
V
S
=
±5V,
Gain = 20, R
L
= 10k
V
S
=
±5V,
Gain = 50, R
L
= 10k
V
S
=
±5V,
Gain = 100, R
L
= 10k
V
S
=
±5V,
Gain = 100, R
L
= 500Ω
–0.1 0.02
–0.1 0.02
–0.1 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.2 0.02
–0.8 0.02
–0.1 0.02
–0.1 0.02
–0.1 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.2 0.02
–0.6 0.02
2
–1.5
–11
–30
–38
–70
–140
1.0
1.0
0.2
1.0
0.4
3.0
3.0
108
107
93
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.2
0.8
0.1
0.1
0.1
0.15
0.15
0.15
0.15
0.15
0.2
0.6
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.2
–1.2
–0.1
–0.1
–0.1
0.02
0.02
0.02
0.02
0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.15 0.02
–0.2
–0.9
0.02
0.02
2
–1.5
–11
–30
–38
–70
–140
1.0
1.0
0.2
1.0
0.4
3.0
3.0
108
107
93
Gain Temperature Coefficient
V
S
= 5V, Gain = 1, R
L
= Open
V
S
= 5V, Gain = 2, R
L
= Open
V
S
= 5V, Gain = 5, R
L
= Open
V
S
= 5V, Gain = 10, R
L
= Open
V
S
= 5V, Gain = 20, R
L
= Open
V
S
= 5V, Gain = 50, R
L
= Open
V
S
= 5V, Gain = 100, R
L
= Open
Channel-to-Channel Gain Temperature V
S
= 5V, Gain = 1, R
L
= Open
Coefficient Match
V
S
= 5V, Gain = 2, R
L
= Open
V
S
= 5V, Gain = 5, R
L
= Open
V
S
= 5V, Gain = 10, R
L
= Open
V
S
= 5V, Gain = 20, R
L
= Open
V
S
= 5V, Gain = 50, R
L
= Open
V
S
= 5V, Gain = 100, R
L
= Open
Channel-to-Channel Isolation (Note 7)
f = 200kHz
V
S
= 5V, Gain = 1, R
L
= 10k
V
S
= 5V, Gain = 10, R
L
= 10k
V
S
= 5V, Gain = 100, R
L
= 10k
Gain = 1
Gain = 10
Gain = 1
Gain = 10
q
q
Offset Voltage Magnitude Referred
to INA or INB Pins (Note 8)
Offset Voltage Magnitude Drift
Referred to INA or INB Pins (Note 8)
2.0
1.1
12
6.6
22
12
2.0
1.1
20
11
22
14
mV
mV
µV/°C
µV/°C
sn691112 691112fs
5