Medical Applications Guide (Rev. B - Mouser Electronics

36➔Diagnostic, Patient Monitoring and TherapyVentilation/Pressure DiscussionComplete Voltage-Output, Programmable BridgeSensor Signal ConditionerPGA309Get samples, datasheets, evaluation modules and app reports at:www.ti.com/sc/device/PGA309The PGA309 is a programmable analog signal conditioner designed forbridge sensors. The analog signal path amplifies the sensor signal andprovides digital calibration for zero, span, zero drift, span drift, andsensor linearization errors with applied stress (pressure, strain, etc.).The calibration is done via a one-wire digital serial interface or througha two-wire industry-standard connection. The calibration parametersare stored in external nonvolatile memory (typically SOT23-5)to eliminate manual trimming and achieve long-term stability.Key Features• Ratiometric or absolute voltage output• Digitally calibrated via single-wire or two-wire interface• Eliminates potentiometer and trimming• Low, time-stable total adjusted error• +2.7V to +5.5V operation• Packaging: Small TSSOP-16Applications• Bridge sensors• Remote 4-20mA transmitters• Strain, load, weight scales• Automotive sensorspsi0 50Non-LinearBridgeTransducerV EXCAnalog Sensor LinearizationV SLinearizationCircuitRefLinearizationDACPWM Low-Side Driver for Valves, Solenoidsand CoilsDRV103Get samples, datasheets, evaluation modules and app reports at:www.ti.com/sc/device/DRV103The DRV103 is a low-side DMOS power switch employing a pulsewidthmodulated (PWM) output. Its rugged design is optimized fordriving electromechanical devices such as valves, solenoid, relays,actuators, motors and positioners. PWM operation conserves powerand reduces heat rise, resulting in higher reliability and its adjustablePWM allows fine control of the power delivered to the load. DC-to-PWM output delay time and oscillator frequency are also externallyadjustable.Key Features• High output drive: 1.5A and 3A versions• Wide supply range: +8V to +32V• Complete function:• Digitally controlled input• PWM output• Adjustable internal oscillator: 500Hz to 100kHz• Adjustable delay and duty cycle• Fully protected:• Thermal and current limit shutdown with status OKindicator flag• Packaging: SO-8, SO-8 PowerPADApplications• Electromechanical driver:• Solenoids, valves, positioners, actuators, relays, powercontactor coils• Hydraulic and pneumatic systems• Medical and scientific analyzers• Chemical processing• Environment monitoring and HVACExtTempFaultMonitorDigital TemperatureCompensationExt TempAuto-ZeroPGAIntTempTempADCOver/UnderScale LimiterAnalog Signal ConditioningControl RegisterInterface CircuitryLinear V OUTDIGITAL CALEEPROM(SOT23-5)DRV103Thermal ShutdownOver CurrentStatus OKFlagDMOS+V SESDOUTFlybackDiodeLoadPGA309 functional block diagram.Input1.3V V REF OscillatorPWMDMOSOffOnDelayI REFDelayAdjC DOsc FreqAdjR FREQ2.75 • IREFDuty CycleAdjR PWMGNDDRV103 functional block diagram.Medical Applications Guide Texas Instruments 2Q 2007