XR18910ILEVB

XR18910 8:1 Sensor Interface Analog Front End Description FEATURES The XR18910 is a unique sensor interface integrated circuit with an Integrated features for interfacing multiple onboard 8:1 multiplexer, offset correction Digital-to-Analog Converter bridge sensors with an MCU or FPGA 2 8:1 differential MUX with I C interface (DAC), instrumentation amplifier and voltage reference. The XR18910 Instrumentation amplifier is designed to integrate multiple bridge sensors with a Microcontroller LDO (MCU) or Field-Programmable Gate Array (FPGA). 2 Offset correction DAC with I C interface The integrated offset correction DAC provides digital calibration of the (560mV offset correction range) variable and in many cases substantial offset voltage generated by the Eight selectable voltage gains from 2V/V 2 bridge sensors. The DAC is controlled by an I C compatible 2-wire serial to 760V/V with only 0.5% gain error interface. The serial interface also provides the user with easy controls 3mV maximum input offset voltage to the XR18910s many functions such as input and gain selection. 100pA maximum input bias current 559A maximum supply current A linear regulator (LDO) provides a regulated voltage to power the input 2.7V to 5V analog supply voltage range bridge sensors and is selectable, between 3V and 2.65V. The LDO 1.8V to 5V digital supply voltage range current can be sensed and a proportional voltage present at the output -40C to 85C temperature range of the IC for monitoring the LDO current. 3.5mm x 3.5mm TQFN-24 package The XR18910 offers 8 fixed gain settings (from 2V/V to 760V/V), each APPLICATIONS 2 with an error of only 0.5%, that are selectable via the I C interface. Bridge sensor interface It also offers less than 3mV maximum input offset voltage, 100pA Pressure and temperature sensors maximum input bias current, and 100pA maximum input offset current. Strain gauge amplifier Industrial process controls The XR18910 is designed to operate from 2.7V to 5V supplies, specified Weigh scales over the industrial temperature range of -40C to 85C and is offered in a space saving 3.5mm x 3.5mm TQFN package. It consumes less than 559A supply current and offers a sleep mode for added power savings. The XR18910 is well suited for industrial and consumer applications using bridge sensors. Typical Application V V DD CC 6.8F 6.8F + + 0.1F 2.5 0.1F 2 BRDG VCC VDD 0.1F 1.5 BRIDGE 8 LDO 1 IN8+ 0.5 IN8- 10k OUT INA / 0 ADC C PGA -0.5 10nF 8:1 MUX 560mV -1 OFFSET TRIM V V DD DD -1.5 BRIDGE 1 10-BIT DAC PGA 4.7k 4.7k -2 IN1+ SDA 2 I C -2.5 IN1- CONTROL SCL 0 2 4 6 8 10 Time (seconds) XR18910 AGND DGND Figure 1. Typical Application Figure 2. 0.1Hz to 10Hz RTI Voltage Noise Rev1C 1/20 RTI Noise (V)XR18910 Absolute Maximum Ratings Operating Conditions Analog supply voltage range .................................... 2.7V to 5.25V Stresses beyond the limits listed below may cause permanent damage to the device. Exposure to any Absolute Digital supply voltage range .......................................1.7V to 5.25V Maximum Rating condition for extended periods may affect Operating temperature range ...................................-40C to 85C device reliability and lifetime. Junction temperature ............................................................150C Analog supply voltage (V .......................................... 0V to 5.5V CC) Storage temperature range .....................................-65C to 150C Digital supply voltage (V ) ........................................... 0V to 5.5V DD Lead temperature (soldering, 10s) ........................................260C Digital input/output (V ) ............................................ 0V to 5.5V DDIO (1) Package thermal resistance ......................................50C/W JA V .....................................................................................0 to V IN CC NOTE: Differential input voltage (current limit of 10mA) ...................... V 1. JEDEC standard, multi-layer test boards, still air. CC ESD rating (HBM - human body model) ...................................4kV Rev1C 2/20