PGA302EPWR

The PGA302 is a low-drift, low-noise, programmable signal conditioner device specifically designed for various resistive bridge sensing applications, such as pressure, temperature, and liquid level sensing applications. The PGA302 also supports flow metering applications using strain gauge load cells, weighing scales and force sensing applications, as well as other general resistive bridge signal conditioning applications. The PGA302 provides a 2.5V bridge excitation voltage and a current output source with a programmable current output of up to 1mA. At the input, this device features two identical analog front-end (AFE) channels, followed by a 16-bit Σ-Δ ADC. Each AFE channel has a dedicated programmable gain amplifier with a gain of up to 200V/V. Additionally, one channel integrates a sensor offset compensation function, and the other channel integrates an internal temperature sensor. At the output of the device, a 14-bit DAC with a 1.25V reference is followed by a ratiometric voltage supply output buffer with a gain of 4V/V, supporting a 0 - 5V ratiometric voltage system output. The PGA302 device uses a third-order temperature coefficient (TC) and nonlinearity (NL) digital compensation algorithm to calibrate the analog output signal. All parameters required for the linearization algorithm and other user data are stored in the integrated EEPROM memory. In terms of system connection, the PGA302 device integrates an I²C interface and a one-wire interface (OWI), supporting communication and configuration through the power line during the final system calibration process. This device implements diagnostic functions at the excitation output source, AFE input, and power supply locations. It also supports system diagnostics, such as sensor open/short circuits. The PGA302 is compatible with various types of sensing elements, such as piezoresistive, ceramic diaphragm, strain gauge, and steel diaphragm. This device can also be used in accelerometer and humidity sensor signal conditioning applications, as well as some applications based on current-sensing shunts.

Applications

• Powertrain pressure sensors
• Powertrain exhaust sensors
• HVAC sensors
• Seat occupancy sensors
• Brake systems
• Battery management systems (BMS)

Key features

• Analog Features:
• Dual-channel analog front-end
• On-chip temperature sensor
• Programmable gain up to 200V/V
• 16-bit Σ-Δ ADC
• Digital Features:
• 3rd-order linear compensation algorithm
• EEPROM for device configuration, calibration data, and user data storage
• I²C interface
• Single-wire interface for communication and configuration via power line
• General Features:
• AFE sensor input, power supply, and output buffer diagnostics
• Memory Built-In Self-Test (MBIST)
• Watchdog
• Power management control