LTC6910-1
LTC6910-2/LTC6910-3
Digitally Controlled
Programmable
Gain Amplifiers in SOT-23
FEATURES
s
s
s
s
s
s
s
s
s
DESCRIPTIO
3-Bit Digital Gain Control in Three Gain-Code
Options
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 Down to 8nV/√Hz
System Dynamic Range to 120dB
Input Offset Voltage: 1.5mV
8-Pin Low Profile (1mm) SOT-23
(ThinSOT™) Package
The LTC
®
6910 family are low noise digitally program-
mable gain amplifiers (PGAs) that are easy to use and
occupy very little PC board space. The inverting gain is
adjustable using a 3-bit digital input to select gains of 0, 1,
2, 5, 10, 20, 50 and 100V/V in the LTC6910-1; 0, 1, 2, 4,
8, 16, 32 and 64V/V in the LTC6910-2; and 0, 1, 2, 3, 4, 5,6
and 7V/V in the LTC6910-3.
The LTC6910-Xs are inverting amplifiers with rail-to-rail
output. 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 LTC6910-X family is
offered in an 8-lead SOT-23 package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
ThinSOT is a trademark of Linear Technology Corporation.
U.S. Patent Number 6121908.
APPLICATIO S
s
s
s
s
Data Acquisition Systems
Dynamic Gain Changing
Automatic Ranging Circuits
Automatic Gain Control
TYPICAL APPLICATIO
Single Supply Programmable Amplifier
V
+
2.7V TO 10.5V
0.1µF
DIGITAL INPUTS GAIN IN VOLTS/VOLT
G2 G1 G0 6910-1 6910-2 6910-3
0
0
0
0
0
0
0
–1
0
–1
1
–1
0
–2
1
–2
0
–2
0
–5
1
–4
1
–3
1
–10
0
–8
0
–4
1
–20
0
–16
1
–5
1
–50
1
–32
0
–6
1
–100
1
–64
1
–7
50
40
4
V
IN
3
LTC6910-X
5
7
6
1
2
AGND
1µF OR LARGER
6910 TA01
GAIN (dB)
8
V
OUT
= GAIN • V
IN
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
6910 TA01b
G2 G1 G0
PIN 2 (AGND) PROVIDES BUILT-IN HALF-SUPPLY
REFERENCE WITH INTERNAL RESISTANCE OF 5k.
AGND CAN ALSO BE DRIVEN BY A SYSTEM ANALOG
GROUND REFERENCE NEAR HALF SUPPLY
–10
100
U
Frequency Response (LTC6910-1)
V
S
= 10V, V
IN
= 5mV
RMS
GAIN OF 100 (DIGITAL INPUT 111)
6910123fa
U
U
1
LTC6910-1
LTC6910-2/LTC6910-3
ABSOLUTE
(Note 1)
AXI U
RATI GS
PACKAGE/ORDER I FOR ATIO
Total Supply Voltage (V+ to V–) ............................. 11V
Input Current .....................................................
±25mA
Operating Temperature Range (Note 2)
LTC6910-1C, -2C, -3C ........................ – 40°C to 85°C
LTC6910-1I, -2I, -3I ........................... – 40°C to 85°C
LTC6910-1H, -2H, -3H .................... – 40°C to 125°C
Specified Temperature Range (Note 3)
LTC6910-1C, -2C, -3C ........................ – 40°C to 85°C
LTC6910-1I, -2I, -3I ........................... – 40°C to 85°C
LTC6910-1H, -2H, -3H .................... – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART NUMBER
LTC6910-1CTS8
LTC6910-1ITS8
LTC6910-1HTS8
LTC6910-2CTS8
LTC6910-2ITS8
LTC6910-2HTS8
LTC6910-3CTS8
LTC6910-3ITS8
LTC6910-3HTS8
TS8 PART MARKING*
LTB5 (6910-1)
LTACQ (6910-2)
LTACS (6910-3)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
*The temperature grades are identified by a label on the shipping container.
TOP VIEW
OUT 1
AGND 2
IN 3
V
–
4
8 V
+
7 G2
6 G1
5 G0
TS8 PACKAGE
8-LEAD PLASTIC TSOT-23
T
JMAX
= 150°C,
θ
JA
= 230°C/W
GAI SETTI GS A D PROPERTIES
Table 1. LTC6910-1
NOMINAL
VOLTAGE GAIN
Volts/Volt
(dB)
0
–120
–1
0
–2
6
–5
14
–10
20
–20
26
–50
34
–100
40
NOMINAL 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
G2
0
0
0
0
1
1
1
1
G1
0
0
1
1
0
0
1
1
G0
0
1
0
1
0
1
0
1
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2
U
W
U
U
W W
U
W
U
U
LTC6910-1
LTC6910-2/LTC6910-3
GAI SETTI GS A D PROPERTIES
Table 2. LTC6910-2
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
NOMINAL 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
0.313
0.188
0.313
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
G2
0
0
0
0
1
1
1
1
G1
0
0
1
1
0
0
1
1
G0
0
1
0
1
0
1
0
1
Table 3. LTC6910-3
NOMINAL
VOLTAGE GAIN
Volts/Volt
(dB)
0
–120
–1
0
–2
6
–3
9.5
–4
12
–5
14
–6
15.6
–7
16.9
NOMINAL 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
3.33
1.67
1
2.5
1.25
0.75
2
1
0.6
1.67
0.83
0.5
1.43
0.71
0.43
NOMINAL
INPUT
IMPEDANCE
(kΩ)
(Open)
10
5
3.3
2.5
2
1.7
1.4
G2
0
0
0
0
1
1
1
1
G1
0
0
1
1
0
0
1
1
G0
0
1
0
1
0
1
0
1
U
U
U
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3
LTC6910-1
LTC6910-2/LTC6910-3
ELECTRICAL CHARACTERISTICS
PARAMETER
Total Supply Voltage
Supply Current
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 SUFFIXES
MIN TYP MAX
q
H SUFFIX
MIN TYP MAX
2.7
2
2.4
3
3.5
12
50
20
90
30
180
10
50
10
80
20
180
±27
±35
10.5
3
3.5
4.5
4.9
30
100
40
160
50
270
20
85
30
150
40
250
UNIT
V
mA
mA
mA
mA
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mV
mA
mA
Specifications for the LTC6910-1, LTC6910-2 and LTC6910-3
2.7
2
2.4
3
3.5
12
50
20
90
30
180
10
50
10
80
20
180
±27
±35
q
10.5
3
3.5
4.5
4.9
30
100
40
160
50
250
20
80
30
150
40
250
V
S
= 2.7V, V
IN
= 1.35V
V
S
= 5V, V
IN
= 2.5V
V
S
=
±5V,
V
IN
= 0V, Pins 5, 6, 7 = – 5V or 5V
V
S
=
±5V,
V
IN
= 0V, Pin 5 = 4.5V,
Pins 6, 7 = 0.5V (Note 4)
V
S
= 2.7V, R
L
= 10k to Midsupply Point
V
S
= 2.7V, R
L
= 500Ω to Midsupply Point
V
S
= 5V, R
L
= 10k to Midsupply Point
V
S
= 5V, R
L
= 500Ω to Midsupply Point
V
S
=
±5V,
R
L
= 10k to 0V
V
S
=
±5V,
R
L
= 500Ω to 0V
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
q
Output Voltage Swing LOW (Note 5)
Output Voltage Swing HIGH (Note 5)
V
S
= 2.7V, R
L
= 10k to Midsupply Point
V
S
= 2.7V, R
L
= 500Ω to Midsupply Point
V
S
= 5V, R
L
= 10k to Midsupply Point
V
S
= 5V, R
L
= 500Ω to Midsupply Point
V
S
=
±5V,
R
L
= 10k to 0V
V
S
=
±5V,
R
L
= 500Ω to 0V
Output Short-Circuit Current (Note 6)
AGND Open-Circuit Voltage
AGND Rejection (i.e., Common Mode
Rejection or CMRR)
Power Supply Rejection Ratio (PSRR)
Signal Attenuation at Gain = 0 Setting
Slew Rate
Digital Input “High” Voltage
V
S
= 2.7V
V
S
=
±5V
V
S
= 5V
2.45
55
55
60
V
S
= 2.7V, V
AGND
= 1.1V to Upper AGND Limit
q
q
V
S
=
±5V,
V
AGND
= –2.5V to 2.5V
V
S
= 2.7V to
±5V
Gain = 0 (Digital Inputs 000), f = 20kHz
V
S
= 5V, V
OUT
= 2.8V
P-P
V
S
=
±5V,
V
OUT
= 2.8V
P-P
V
S
= 2.7V
V
S
= 5V
V
S
=
±5V
V
S
= 2.7V
V
S
= 5V
V
S
=
±5V
V
–
≤
(Digital Input)
≤
V
+
q
q
q
q
q
q
q
q
2.5
80
75
80
– 122
12
16
2.55
2.45
50
50
60
2.5
80
75
80
– 122
12
16
2.55
V
dB
dB
dB
dB
V/µs
V/µs
V
V
V
2.43
4.5
4.5
0.27
0.5
0.5
2
2.43
4.5
4.5
0.27
0.5
0.5
2
Digital Input “Low” Voltage
V
V
V
µA
Digital Input Leakage Current Magnitude
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4
LTC6910-1
LTC6910-2/LTC6910-3
ELECTRICAL CHARACTERISTICS
PARAMETER
Specifications for LTC6910-1 Only
Voltage Gain (Note 7)
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.
LTC6910-1C/LTC6910-1I
LTC6910-1H
MIN TYP MAX
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
UNIT
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
mV
µV/°C
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
– 0.05 0
0.07
– 0.1 – 0.02 0.06
5.96
6.02
6.08
13.85 13.95 14.05
19.7 19.9 20.1
19.6 19.85 20.1
25.7
33.5
39
37.4
25.9
33.8
39.6
39
26.1
34.1
40.2
40.1
– 0.06 0
0.07
– 0.12 – 0.02 0.08
5.96
6.02
6.08
13.83 13.95 14.05
19.7 19.9 20.1
19.4 19.85 20.1
25.65 25.9
33.4
33.8
38.7 39.6
36.4 39
26.1
34.1
40.2
40.1
– 0.05 0
0.07
– 0.1 – 0.01 0.08
5.96
6.02
6.08
13.8 13.95 14.1
19.8 19.9 20.1
19.6 19.85 20.1
25.8
33.5
39.3
38
25.9
33.8
39.7
39.2
26.1
34.1
40.1
40.1
– 0.05 0
0.07
– 0.11 – 0.01 0.08
5.955 6.02
6.08
13.75 13.95 14.1
19.75 19.9 20.1
19.45 19.85 20.1
25.70 25.9
33.4
39.1
37
33.8
26.1
34.1
39.7 40.1
39.2 40.1
– 0.05 0
0.07
– 0.1 – 0.01 0.08
5.96
19.8
19.7
6.02
19.9
19.9
6.08
20.1
20.1
34
40.2
40.1
9
13.80 13.95 14.1
– 0.05 0
0.07
– 0.1 – 0.01 0.08
5.96
6.02
6.08
20.1
20.1
34
40.2
40.1
11
13.80 13.95 14.1
19.75 19.9
19.6 19.9
33.6 33.85
39.25 39.8
38 39.6
1.5
8
25.8 25.95 26.1
33.7 33.85
39.4
38.8
39.8
39.6
1.5
6
25.75 25.95 26.1
Offset Voltage Magnitude (Internal Op Amp)
(V
OS(OA)
) (Note 8)
Offset Voltage Drift (Internal Op Amp) (Note 8)
Offset Voltage Magnitude
(Referred to “IN” Pin) (V
OS(IN)
)
DC Input Resistance (Note 9)
Gain = 1
Gain = 10
DC V
IN
= 0V
Gain = 0
Gain = 1
Gain = 2
Gain = 5
Gain = 10, 20, 50, 100
q
q
3
1.7
>100
10
5
2
1
15
10
3
1.7
>100
10
5
2
1
18
12
mV
mV
MΩ
kΩ
kΩ
kΩ
kΩ
q
q
q
q
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