Programmable-gain amplifier for precision sensor front-ends
It combines a 560 kHz gain-bandwidth product with a 110 kHz -3 dB bandwidth, a 0.12 V/µs slew rate, and rail-to-rail output swing — characteristics that suit it for conditioning signals from strain gauges, thermocouples, and bridge sensors where the gain needs to be set by external resistors rather than a fixed topology. The 25 µV input offset voltage and 2.5 nA input bias current keep DC errors low enough that many applications can skip a software calibration step. Supply range from 2.7 V to 36 V means the same part can serve a 3.3 V battery-powered data logger or a 24 V industrial transmitter without a rail converter.
Supply current and output drive — sizing for always-on and loop-powered designs
At 130 µA supply current, the LT1991IDD#PBF fits into power budgets where every microamp counts — think 4-20 mA loop-powered transmitters or battery-backed sensor nodes that stay awake continuously. If the load is purely resistive and the signal bandwidth stays under 110 kHz, the 0.12 V/µs slew rate is sufficient to maintain linearity; for faster edges, a wider-bandwidth PGA would be needed.
Package and thermal — what the 10-DFN exposed pad means for the board
The exposed pad is also the ground return for the die substrate — the layout should connect it to the analog ground plane with a low-impedance path, not leave it floating.