Product Details
●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 µs 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.
●The AD585 can be used with any user-defined feedback net-work to provide any desired gain in the sample mode. On-chip precision thin-film resistors can be used to provide gains of +1, -1, or +2. Output impedance in the hold mode is sufficiently low to maintain an accurate output signal even when driving the dynamic load presented by a successive-approximation A/D converter. However, the output is protected against damage from accidental short circuits.
●The control signal for the HOLD command can be either active high or active low. The differential HOLD signal is compatible with all logic families, if a suitable reference level is provided. An on-chip TTL reference level is provided for TTL compatibility.
●The AD585 is available in three performance grades. The JP grade is specified for the 0°C to +70°C commercial temperature range and packaged in a 20-pin PLCC. The AQ grade is specified for the -25°C to +85°C industrial temperature range and is packaged in a 14-pin cerdip. The SQ and SE grades are specified for the -55°C to +125°C military temperature range and are packaged in a 14-pin cerdip and 20-pin LCC.
●### Features and Benefits
● 3.0 ms Acquisition Time to 60.01% max
● Low Droop Rate: 1.0 mV/ms max
● Sample/Hold Offset Step: 3 mV max
● Aperture Jitter: 0.5 ns
● Extended Temperature Range: –55°C to +125°C
● Internal Hold Capacitor
● Internal Application Resistors
● See datasheet for additional features