LTC6912
Dual Programmable
Gain Amplifiers with
Serial Digital Interface
FEATURES
DESCRIPTIO
2 Channels with Independent Gain Control The LTC 6912 is a family of dual channel, low noise,
LTC6912-1: (0, 1, 2, 5, 10, 20, 50, and 100V/V)
digitally programmable gain amplifiers (PGA) that are
LTC6912-2: (0, 1, 2, 4, 8, 16, 32, and 64V/V)
easy to use and occupy very little PC board space. The
Offset Voltage = 2mV Max (40C to 85C)
gains for both channels are independently programmable
Channel-to-Channel Gain Matching of 0.1dB Max
using a 3-wire SPI interface to select voltage gains of 0, 1,
TM
3-Wire SPI Interface
2, 5, 10, 20, 50, and 100V/V (LTC6912-1 ); and 0, 1, 2, 4,
Extended Gain-Bandwidth at High Gains
8, 16, 32, and 64V/V (LTC6912-2). All gains are inverting.
Wired-OR Outputs Possible (2:1 Analog MUX
The LTC6912 family consists of 2 matched amplifiers with
Function)
rail-to-rail outputs. When operated with unity gain, they
Low Power Hardware Shutdown (GN-16 Only,
will also process rail-to-rail input signals. A half-supply
2A Max at 2.7V)
reference generated internally at the AGND pin supports
Rail-to-Rail Input Range
single power supply applications. Operating from single
Rail-to-Rail Output Swing
or split supplies from 2.7V to 10.5V total, the LTC6912-X
Single or Dual Supply: 2.7V to 10.5V Total
family is offered in tiny SSOP and DFN-12 Packages.
Input Noise: 12.6nV/Hz
Total System Dynamic Range to 115dB
16-Pin GN (SSOP) or 12-Pin DFN Package Options
, LTC and LT are registered trademarks of Linear Technology Corporation.
U
All other trademarks are the property of their respective owners.
APPLICATIO S
Data Acquisition Systems
Dynamic Gain Changing
Automatic Ranging Circuits
Automatic Gain Control
TYPICAL APPLICATIO
A Dual, Matched Low Noise PGA (16-Lead SSOP Package)
3V
0.1F
LTC6912-2
12 14
Frequency Response
+
V V
40
V = 2.5V
GAIN OF 64 S
V = 10mV
IN RMS
2 INA OUT A 15
V V = GAIN V
INA OUTA A INA GAIN OF 32
30
1F GAIN OF 16
3
LTC6912-X
AGND
20 GAIN OF 8
GAIN OF 4
4 INB OUT B 13
10
V V = GAIN V
INB OUTB B INB
GAIN OF 2
GAIN OF 1
0
10
CHB CHA
5
0.1 1 10 100 1000 10000
SHDN SHDN 10
DGND
6
FREQUENCY (kHz)
CS/LD CS/LD
3-WIRE
7 6912 TA01b
SPI DATA D
IN 9
D
8
OUT
INTERFACE
CLK
6912 TA01a
6912fa
1
GAIN (dB)
U
ULTC6912
ABSOLUTE AXI U RATI GS
(Note 1)
Specified Temperature Range (Note 3)
+
Total Supply Voltage (V to V ) ............................... 11V
LTC6912C-1, LTC6912C-2 ..................40C to 85C
Input Current ...................................................... 10mA
LTC6912I-1, LTC6912I-2.....................40C to 85C
Operating Temperature Range (Note 2)
LTC6912H-1, LTC6912H-2
LTC6912C-1, LTC6912C-2 ..................40C to 85C
(GN-16 Only) .....................................40C to 125C
LTC6912I-1, LTC6912I-2.....................40C to 85C
Storage Temperature Range ..................65C to 150C
LTC6912H-1, LTC6912H-2
UE Package ....................................... 65C to 125C
(GN-16 Only) .....................................40C to 125C
Lead Temperature (Soldering, 10sec)................... 300C
UUW
PACKAGE/ORDER I FOR ATIO
TOP VIEW TOP VIEW
NC 1
16 NC
INA 1 12 OUTA
INA 2 15
OUT A
AGND 2 11 V
AGND 3 14
V
INB 3 10 OUTB
13
INB 4 13
OUT B
+
CS/LD 4 9 V
+
SHDN 5 12
V
DIN 5 8 DGND
CS/LD 6 11
NC
CLK 6 7 DOUT
D 7 10
DGND
IN
UE12 PACKAGE
CLK 8 9
D
OUT
12-LEAD (4mm 3mm) PLASTIC DFN
EXPOSED PAD IS CONNECTED TO V (PIN 13),
GN PACKAGE
MUST BE SOLDERED TO PCB
16-LEAD NARROW PLASTIC SSOP
T = 125C, = 160C/W T = 150C, = 120C/W
JMAX JA JMAX JA
ORDER PART DFN PART* ORDER PART GN PART
NUMBER MARKING NUMBER MARKING
LTC6912CGN-1 69121
LTC6912CDE-1 69121 LTC6912IGN-1 6912I1
LTC6912IDE-1 69121 LTC6912HGN-1 6912H1
LTC6912CDE-2 69122 LTC6912CGN-2 69122
LTC6912IDE-2 69122 LTC6912IGN-2 6912I2
LTC6912HGN-2 6912H2
Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF
Lead Free Part Marking: