LTC6915 Datasheet, PDF (1/16 Pages) Linear Technology – Zero Drift, Precision Instrumentation Amplifier with Digitally Programmable Gain

FEATURES
s _{14 Levels of Programmable Gain}
s _{125dB CMRR Independent of Gain}
s _{Gain Accuracy 0.1% (Typ)}
s _{Maximum Offset Voltage of 10µV}
s _{Maximum Offset Voltage Drift: 50nV/°C}
s _{Rail-to-Rail Input and Output}
s _{Parallel or Serial (SPI) Interface for Gain Setting}
s _{Supply Operation: 2.7V to ±5.5V}
s _{Typical Noise: 2.5µVP-P (0.01Hz to 10Hz)}
s _{16-Lead SSOP and 12-Lead DFN Packages}
U
APPLICATIO S
s _{Thermocouple Amplifiers}
s _{Electronic Scales}
s _{Medical Instrumentation}
s _{Strain Gauge Amplifier}
s _{High Resolution Data Acquisition}
LTC6915
Zero Drift, Precision
Instrumentation Amplifier with
Digitally Programmable Gain
DESCRIPTIO
The LTC^®6915 is a precision programmable gain instru-
mentation amplifier. The gain can be programmed to 0, 1,
2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, or 4096
through a parallel or serial interface. The CMRR is typically
125dB with a dual 5V supply with any programmed gain.
The offset is below 10µV with a temperature drift of less
than 50nV/°C.
The LTC6915 uses charge balanced sampled data tech-
niques to convert a differential input voltage into a single
ended signal that is in turn amplified by a zero-drift
operational amplifier.
The differential inputs operate from rail-to-rail and the
single-ended output swings from rail-to-rail. The LTC6915
can be used in single power supply applications as low as
2.7V, or with dual ±5V supplies. The LTC6915 is available
in a 16-lead SSOP package and a 12-lead DFN surface
mount package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
Differential Bridge Amplifier with Gain Programmed through the Serial Interface
3V
R < 10k
LTC6915 SSOP PACKAGE
3 IN⁺
_
2 IN
C_S
C_H
+
–
C_F
11 PARALLEL_SERIAL
OUT 15
SENSE 14
RESISTOR
ARRAY
REF 13
6 CS(D0)
µP
7 DIN(D1)
8 CLK(D2)
TO OTHER ^{9 DOUT(D3)}
DEVICES
MUX
4-BIT
LATCH
Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7
8-BIT
SHIFT-REGISTER
HOLD_THRU 5
V^{+ 16} 3V
0.1µF
SHDN ¹
DGND ¹⁰
V^{– 4}
6915 TA01
6915f
1