High-speed voltage feedback amp, 500 MHz bandwidth
The OPA843ID is a voltage feedback amplifier from Texas Instruments, offering a -3dB bandwidth of 500 MHz and a gain bandwidth product of 800 MHz. This combination makes it suitable for high-speed signal conditioning, video distribution, and ADC driver stages where wide flat gain is needed before the loop rolls off. Slew rate is 1000 V/µs, which means the output can swing 5 V in 5 ns — fast enough to reproduce a 100 MHz square wave without visible rounding on a scope. The 20.2 mA supply current is the price you pay for that speed; it runs warm in the 8-SOIC package, so the board copper under the device helps pull heat away. Supply span is 8 V to 12 V single or split — a ±5 V rail pair fits right in the middle. Input bias current is 20 µA (bipolar input stage), and input offset voltage is 300 µV typical. For a DC-coupled photodiode front-end, that offset may need a trim or a downstream servo loop.
Package, temperature grade, and lifecycle
ROHS3 compliant per the lifecycle record.