Overview
The AD684JQ, produced by Analog Devices Inc., is a monolithic quad sample-and-hold amplifier (SHA) designed for high-performance, multichannel data acquisition systems. This device features four complete sampling channels, each controlled by an independent hold command, making it ideal for applications requiring simultaneous sampling of multiple signals.
The AD684JQ is manufactured using a BiMOS process, combining the benefits of high-performance bipolar circuitry and low-power CMOS logic. This architecture ensures excellent interchannel matching, high reliability, and superior system accuracy.
Key Specifications
| Parameter | Min | Typ | Max | Units |
|---|---|---|---|---|
| Acquisition Time (10 V Step to 0.01%) | 0.75 | 1.0 | 1.0 | µs |
| Acquisition Time (10 V Step to 0.1%) | 0.5 | 0.6 | 0.6 | µs |
| Small Signal Bandwidth | 4 | 4 | 4 | MHz |
| Full Power Bandwidth | 1 | 1 | 1 | MHz |
| Effective Aperture Delay | -35 | -25 | -15 | ns |
| Aperture Jitter | 50 | 75 | 50 | ps |
| Hold Settling Time (to 1 mV) | 250 | 500 | 500 | ns |
| Droop Rate | 0.01 | 1 | 1 | µV/µs |
| Feedthrough (VIN = ± 5 V, 100 kHz) | -90 | -90 | -90 | dB |
| Hold Mode Offset | -4 | -1 | +3 | mV |
| Hold Mode Offset Drift | 10 | 10 | 10 | µV/°C |
| Sample Mode Offset | 50 | 200 | 50 | mV |
| Input Impedance | 50 | 50 | 50 | MΩ |
| Input Capacitance | 2 | 2 | 2 | pF |
| Operating Voltage Range (VCC, VEE) | ±10.8 | ±12 | ±13.2 | V |
| Supply Current | 18 | 25 | 26 | mA |
| Power Consumption | 430 | 600 | 625 | mW |
| Temperature Range | 0 to +70°C (J grade) | -40 to +85°C (A grade) | -55 to +125°C (S grade) | °C |
Key Features
- Fast Acquisition Time: The AD684JQ has a fast acquisition time of less than 1 µs, making it suitable for high-speed data acquisition systems.
- Low Aperture Jitter: With an aperture jitter of 75 ps, this device ensures high accuracy and precision in sampling.
- Independent Channels: Each of the four sampling channels is controlled by an independent hold command, allowing for flexible system architecture.
- Low Droop Rate: The device features a low droop rate of 0.01 µV/µs, ensuring that the held value is retained accurately.
- High Accuracy and Linearity: The AD684JQ is designed for high accuracy and linearity, making it an ideal front end for high-speed 12- and 14-bit ADCs.
- Output Short Circuit Protection: Each channel can source up to 5 mA and includes output short circuit protection.
- Temperature Stability: The device is specified for three temperature ranges, ensuring reliable performance across various environmental conditions.
Applications
- High-Speed Data Acquisition Systems: The AD684JQ is ideal for systems that require simultaneous sampling of multiple signals at high speeds.
- Analog-to-Digital Converters (ADCs): It is particularly suited as a front end for high-speed 12- and 14-bit ADCs due to its fast settling time and low output impedance.
- Industrial and Military Applications: Available in versions compliant with MIL-STD-883, the AD684JQ is suitable for both industrial and military applications requiring high reliability and performance.
- Medical and Scientific Instruments: Its high accuracy and precision make it a good fit for medical and scientific instruments that require reliable data acquisition.
Q & A
- What is the AD684JQ?
The AD684JQ is a monolithic quad sample-and-hold amplifier (SHA) produced by Analog Devices Inc.
- How many sampling channels does the AD684JQ have?
The AD684JQ features four complete sampling channels, each controlled by an independent hold command.
- What is the acquisition time of the AD684JQ?
The acquisition time is less than 1 µs for a 10 V step to 0.01% accuracy.
- What is the aperture jitter of the AD684JQ?
The aperture jitter is 75 ps.
- What is the droop rate of the AD684JQ?
The droop rate is 0.01 µV/µs.
- Can the AD684JQ be used in high-speed ADC applications?
Yes, it is ideal for driving high-speed analog to digital converters due to its fast settling time and low output impedance.
- What are the temperature ranges for the AD684JQ?
The device is specified for three temperature ranges: 0 to +70°C (J grade), -40 to +85°C (A grade), and -55 to +125°C (S grade).
- Does the AD684JQ have output short circuit protection?
Yes, each channel can source up to 5 mA and includes output short circuit protection.
- Is the AD684JQ suitable for military applications?
Yes, it is available in versions compliant with MIL-STD-883.
- What is the typical supply current of the AD684JQ?
The typical supply current is 25 mA.
