hi friend
Now it is a popular for us to do business online.
Not only IC seller or IC buyer ,you should know IC model tech infor
I like to find their datasheet and PDF from IC trade platform which I can free downoad its datasheet
eg:
High Speed, Precision Sample-and-Hold Amplifier

more detail from http://www.chinaicmart.com/series-596/5962-8754001CA.html

PRODUCT DESCRIPTION

The AD585 is a complete monolithic sample-and-hold circuit consisting of a high performance operational amplifier in series with an ultralow leakage analog switch and a FET input integrating amplifier. An internal holding capacitor and matched applications resistors have been provided for high precision and applications flexibility.

The performance of the AD585 makes it ideal for high speed 10- and 12-bit data acquisition systems, where fast acquisition time, low sample-to-hold offset, and low droop are critical. The AD585 can acquire a signal to ?0.01% in 3 ms maximum, and then hold that signal with a maximum sample-to-hold offset of 3 mV and less than 1 mV/ms droop, using the on-chip hold capacitor. If lower droop is required, it is possible to add a larger external hold capacitor.

The high speed analog switch used in the AD585 exhibits aperture jitter of 0.5 ns, enabling the device to sample full scale (20 V peak-to-peak) signals at frequencies up to 78 kHz with 12-bit precision.