Four-Channel a Sample-and-Hold Amplifier AD684 FEATURES FUNCTIONAL BLOCK DIAGRAM Four Matched Sample-and-Hold Amplifiers Independent Inputs, Outputs and Control Pins 500 ns Hold Mode Settling 1 ms Maximum Acquisition Time to 0.01% Low Droop Rate: 0.01 mV/ms Internal Hold Capacitors 75 ps Maximum Aperture Jitter Low Power Dissipation: 430 mW 0.3 Skinny DIP Package MIL-STD-883 Compliant Versions Available PRODUCT DESCRIPTION PRODUCT HIGHLIGHTS The AD684 is a monolithic quad sample-and-hold amplifier 1. Fast acquisition time (1 s) and low aperture jitter (75 ps) (SHA). It features four complete sampling channels, each make the AD684 the best choice for multiple channel data controlled by an independent hold command. Each SHA is acquisition systems. complete with an internal hold capacitor. The high accuracy 2. Monolithic construction insures excellent interchannel SHA channels are self-contained and require no external matching in terms of timing and accuracy, as well as high components or adjustments. The AD684 is manufactured on a reliability. BiMOS process which provides a merger of high performance 3. Independent inputs, outputs and sample-and-hold controls bipolar circuitry and low power CMOS logic. allow user flexibility in system architecture. The AD684 is ideal for high performance, multichannel data 4. Low droop (0.01 V/s) and internally compensated hold acquisition systems. Each SHA channel can acquire a signal in mode error results in superior system accuracy. less than 1 s and retain the held value with a droop rate of less than 0.01 V/s. Excellent linearity and ac performance make 5. The AD684s fast settling time and low output impedance the AD684 an ideal front end for high speed 12- and 14-bit make it ideal for driving high speed analog to digital ADCs. converters such as the AD578, AD674, AD7572 and the AD7672. The AD684 has a self-correcting architecture that minimizes hold mode errors and insures accuracy over temperature. Each 6. The AD684 is available in versions compliant with MIL- channel of the AD684 is capable of sourcing 5 mA and STD-883. Refer to the Analog Devices Military Products incorporates output short circuit protection. Databook or current AD684/883B data sheet for detailed specifications. The AD684 is specified for three temperature ranges. The J grade device is specified for operation from 0 to +70C, the A grade from 40C to +85C and the S grade from 55C to +125C. REV. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 617/329-4700 Fax: 617/326-8703(T to T with V = +12 V 6 10%, V = 12 V 6 10%, unless otherwise noted) AD684SPECIFICATIONS MIN MAX CC EE AD684J AD684A AD684S Parameter Min Typ Max Min Typ Max Min Typ Max Units SAMPLING CHARACTERISTICS Acquisition Time 10 V Step to 0.01% 0.75 1.0 0.75 1.0 0.75 1.0 s 10 V Step to 0.1% 0.5 0.6 0.5 0.6 0.5 0.6 s Small Signal Bandwidth 4 4 4 MHz Full Power Bandwidth 1 1 1 MHz HOLD CHARACTERISTICS Effective Aperture Delay 35 25 15 35 25 15 35 25 15 ns Aperture Jitter 50 75 50 75 50 75 ps Hold Settling Time (to 1 mV) 250 500 250 500 250 500 ns l Droop Rate 0.01 1 0.01 1 0.01 1 V/s Feedthrough (V = 5 V, 100 kHz) 90 90 90 dB IN 1 ACCURACY CHARACTERISTICS Hold Mode Offset 4 1 +3 4 1 +3 4 1 +3 mV Hold Mode Offset Drift 10 10 10 V/C Sample Mode Offset 50 200 50 200 50 200 mV Nonlinearity 0.002 0.003 0.002 0.003 0.003 0.005 % FS Gain Error 0.03 60.05 0.03 60.05 0.03 60.05 % FS INTERCHANNEL CHARACTERISTICS Interchannel Isolation (V = 5 V, 100 kHz) 80 86 80 86 80 86 dB IN Interchannel Aperture Offset 150 300 150 300 150 300 ps Interchannel Offset 0.4 1.5 0.4 2.0 0.4 2.0 mV OUTPUT CHARACTERISTICS 2 Output Drive Current 5 +5 5 +5 5 +5 mA Output Resistance, dc 0.3 0.5 0.3 0.5 0.3 0.5 Total Output Noise (dc to 5 MHz) 150 150 150 V rms Sampled dc Uncertainty 85 85 85 V rms Hold Mode Noise (dc to 5 MHz) 125 125 125 V rms 3 Short Circuit Current Source 20 20 20 mA Sink 10 10 10 mA INPUT CHARACTERISTICS Input Voltage Range 5 +5 5 +5 5 +5 V 4 Bias Current 100 250 100 250 100 250 nA 400 500 500 nA Input Impedance 50 50 50 M Input Capacitance 2 2 2 pF DIGITAL CHARACTERISTICS Input Voltage Low 0.8 0.8 0.8 V Input Voltage High 2.0 2.0 2.0 V Input Current (V = 5 V) 2 10 2 10 2 10 A IN POWER SUPPLY CHARACTERISTICS Operating Voltage Range (V , V ) 10.8 12 13.2 10.8 12 13.2 10.8 12 13.2 V CC EE Supply Current 18 25 18 25 18 26 mA +PSRR 65 70 65 70 65 70 dB PSRR 60 65 60 65 60 65 dB Power Consumption 430 600 430 600 430 625 mW TEMPERATURE RANGE Specified Performance 0 +70 40 +85 55 +125 C PACKAGE OPTIONS 16-Pin Cerdip (Q) AD684JQ AD684AQ AD684SQ NOTES 1 Specified and tested over an input range of 5 V. 2 Maximum current the AD684 can source (or sink). Testing guarantees that the accuracy of the held signal remains within 2.5 mV of its initial value. 3 The output is protected for a short circuit to common, V and V . CC EE 4 V and V at nominal voltage levels. CC EE Specifications shown in boldface are tested on all production units at final electrical test. Results from those tests are used to calculate outgoing quality levels. All min and max specifications are guaranteed, although only those shown in boldface are tested on all production units. Specifications subject to change without notice. 2 REV. A