Texas Instruments has added to its range of digitally calibrated sensor signal conditioning ICs with a single-supply, auto-zero bridge sensor amplifier that has been designed as a building block for resistive bridge sensor conditioning and general data acquisition applications.
At the heart of the PGA308 is a low-drift and low-noise front-end programmable gain amplifier (PGA). According to TI, digital-programmable coarse offset, fine offset and selected gain (coarse and fine) may be controlled in real time or permanently programmed into the PGA308. Seven banks of one-time programmable (OTP) memory of gain and offset calibration parameters can be stored on the device, whilst a separate power-on reset (POR) OTP bank can be programmed up to four times.
Calibration is done via the 1W pin, a UART-compatible digital serial interface.
The PGA308 has an operating voltage of +2.7 to +5.5V. TI claims 'excellent precision and noise' over an extended industrial temperature range of -40°C to +125°C, thanks to the use of auto-zero techniques.
The PGA308 is already shipping in a MSOP-10 package and a 3 x 4mm DFN-10 package. A hardware and software PGA308EVM evaluation tool is available for
calibration and configuration.