LTC6915 Zero Drift, Precision Instrumentation Amplifier with Digitally Programmable Gain FeaTuresDescripTion n 14 Levels of Programmable Gain The LTC®6915 is a precision programmable gain instru- n 125dB CMRR Independent of Gain mentation amplifier. The gain can be programmed to 0, n Gain Accuracy 0.1% (Typ) 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, or 4096 n Maximum Offset Voltage of 10µV through a parallel or serial interface. The CMRR is typi- n Maximum Offset Voltage Drift: 50nV/°C cally 125dB with a single 5V supply with any programmed n Rail-to-Rail Input and Output gain. The offset is below 10µV with a temperature drift of n Parallel or Serial (SPI) Interface for Gain Setting less than 50nV/°C. n Supply Operation: 2.7V to ±5.5V The LTC6915 uses charge balanced sampled data tech- n Typical Noise: 2.5µVP-P (0.01Hz to 10Hz) niques to convert a differential input voltage into a single n 16-Lead SSOP and 12-Lead DFN Packages ended signal that is in turn amplified by a zero-drift op- erational amplifier. applicaTions The differential inputs operate from rail-to-rail and the n Thermocouple Amplifiers single-ended output swings from rail-to-rail. The LTC6915 n Electronic Scales can be used in single power supply applications as low as n Medical Instrumentation 2.7V, or with dual ±5V supplies. The LTC6915 is available n Strain Gauge Amplifier in a 16-lead SSOP package and a 12-lead DFN surface n High Resolution Data Acquisition mount package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners Typical applicaTionDifferential Bridge Amplifier with Gain Programmed through the Serial Interface LTC6915 SSOP PACKAGE 3 IN+ + 3V OUT 15 CS CH _ – SENSE 14 2 IN CF R < 10k RESISTOR ARRAY REF 13 11 PARALLEL_SERIAL HOLD_THRU 5 MUX 4-BIT LATCH V+ 16 3V 0.1µF 6 CS(D0) Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 7 D µP IN(D1) 1 8-BIT SHDN 8 CLK(D2) SHIFT-REGISTER DGND 10 TO OTHER 9 DOUT(D3) 4 V– DEVICES 6915 TA01 6915fb 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagrams Timing Diagram Operation Typical Application Package Description Revision History Typical Application Related Parts
