DESCRIPTION
The LF198/LF298/LF398 are monolithic sample-and-hold circuits which utilize high-voltage ion-implant JFET technology to obtain ultra-high DC accuracy with fast acquisition of signal and low droop rate. Operating as a unity gain follower, DC gain accuracy is 0.002% typical and acquisition time is as low as 6µs to 0.01%. A bipolar input stage is used to achieve low offset voltage and wide bandwidth. Input offset adjust is accomplished with a single pin and does not degrade input offset drift. The wide bandwidth allows Input impedance of 1010Ω allows high source impedances to be used without degrading accuracy. P-channel junction FETs are combined with bipolar devices in the output amplifier to give droop rates as low as 5mV/min with a 1µF hold capacitor. Logic inputs are fully differential with low input current, allowing direct connection to TTL, PMOS, and CMOS; differential threshold is 1.4V. The LF198/LF298/LF398 will operate from ±5V to ±18V supplies. They are available in 8-pin plastic DIP, 8-pin Cerdip, and 14-pin plastic SO packages.
NXP Semiconductors
