2.7 GHz GBWP, 1400 V/µs — what the speed ratings mean for the signal chain
The OPA818IDRGT is a single-channel JFET-input operational amplifier from Texas Instruments, offering a 2.7 GHz gain-bandwidth product and a 1400 V/µs slew rate. These two numbers together define the large-signal and small-signal bandwidth: the GBWP sets the closed-loop bandwidth at a given gain (e.g., 270 MHz at a gain of 10), while the slew rate determines how fast the output can swing under a large step input — 1400 V/µs means it slews 1.4 V in 1 ns, critical for driving ADC inputs or pulse-recovery stages where the signal edge must not be the limiting factor. The -3 dB bandwidth of 765 MHz confirms the small-signal flatness extends well into the UHF band. For a photodiode transimpedance amplifier or a high-speed data acquisition front-end, this bandwidth supports settling times in the sub-nanosecond range, provided the feedback network and layout do not add parasitic poles.
JFET input stage — bias current and noise floor for high-impedance sources
The JFET input stage gives a typical input bias current of 25 pA at 25 °C. This is the key spec for a sensor front-end: a 10 MΩ source impedance sees only 250 µV of offset from bias current, negligible compared to the 1.25 mV typical input offset voltage. The bias current doubles roughly every 10 °C, so at 85 °C it sits near 400 pA — still acceptable for most high-impedance paths, but worth derating for a 100 MΩ piezoelectric sensor. Supply current is 26.5 mA typical, drawn from a single supply span of 6 V to 13 V. The 110 mA output current per channel gives enough drive to swing into a 50 Ω load or a 100 Ω feedback network without significant gain compression.
Package and thermal — 8-SON with exposed pad
Housed in an 8-WFDFN exposed-pad package (3×3 mm body, 8-SON), the OPA818IDRGT requires a thermal-land pattern on the PCB. Tape & Reel (TR) and Cut Tape (CT) options are available for production and prototyping quantities respectively.
Lifecycle and supply-chain posture
For BOM planning, the active status means no imminent obsolescence risk.