JFET input stage for high-impedance sensor front-ends
The OPA810IDBVR is a single-channel JFET-input operational amplifier from Texas Instruments, built for signal chains that need both wide bandwidth and low input bias current. With an input bias current of 2 pA typical, this part suits photodiode amplifiers, piezoelectric sensors, and other high-source-impedance front-ends where bias current drift would otherwise swamp the signal. The 254 V/µs slew rate and 140 MHz -3 dB bandwidth mean the amplifier can track fast transients — think high-speed data acquisition or wideband transimpedance stages — without slewing into distortion. Gain-bandwidth product is 70 MHz, so at a closed-loop gain of 10 the usable bandwidth is about 7 MHz before the open-loop roll-off cuts in.
Rail-to-rail output and supply flexibility
The push-pull rail-to-rail output stage swings within millivolts of both supply rails, maximising dynamic range in single-supply or low-voltage systems. Supply span runs from 4.75 V minimum to 27 V maximum, covering common 5 V and ±15 V rails as well as 12 V and 24 V industrial buses. Output can source or sink up to 100 mA per channel, enough to drive an ADC input, a coaxial cable, or a small relay coil directly. Input offset voltage is 100 µV typical — adequate for most precision signal conditioning but worth budgeting if the application demands sub-millivolt DC accuracy across temperature.
SOT-23-5 package and rework reality
Housed in a SOT-23-5 (SC-74A) package, the OPA810IDBVR is a five-pin surface-mount device with a 0.95 mm pitch — easy to hand-solder or rework with a fine-tip iron and hot air. Pin 1 is clearly marked by a chamfer on the package body, so orientation is unambiguous under a loupe or automated vision system.
Industrial temperature range and active lifecycle
Rated for -40 °C to +125 °C ambient, this amplifier is specified for industrial and automotive-adjacent environments — motor drives, engine-bay sensor interfaces, outdoor telecom gear.
