Features and Benefits
- AC and DC Characterized and Specified: K, B and T Grades
- 200k Conversions per Second
- 1 MHz Full Power Bandwidth; 500 kHz Full Linear Bandwidth
- 72 dB S/N+D (K, B, T Grades)
- Two's Complement Data Format (Bipolar Mode)
- Straight Binary Data Format (Unipolar Mode)
- 10 M Ω Input Impedance
- 8-Bit or 16-Bit Bus Interface
- On-Board Reference and Clock
- 10 V Unipolar or Bipolar Input Range
- Commercial, Industrial and Military Temperature Range Grades
- MIL-STD-883 Compliant Versions Available
The AD678 is a complete, multipurpose 12-bit monolithic analog-to-digital converter, consisting of a sample-hold amplifier (SHA), a microprocessor compatible bus interface, a voltage reference and clock generation circuitry.
The AD678 is specified for ac (or "dynamic") parameters such as S/N+D ratio, THD and IMD which are important in signal processing applications. In addition, the AD678K, B and T grades are fully specified for dc parameters which are important in measurement applications.
The AD678 offers a choice of digital interface formats; the 12 data bits can be accessed by a 16-bit bus in a single read operation or by an 8-bit bus in two read operations (8+4), with right or left justification. Data format is straight binary for unipolar mode and twos complement binary for bipolar mode. The input has a full-scale range of 10 V with a full power bandwidth of 1 MHz and a full linear bandwidth of 500 kHz. High input im-pedance (10 M(ohm)) allows direct connection to unbuffered sources without signal degradation.
This product is fabricated on Analog Devices' BiMOS process, combining low power CMOS logic with high precision, low noise bipolar circuits; laser-trimmed thin-film resistors provide high accuracy. The converter utilizes a recursive subranging algorithm which includes error correction and flash converter circuitry to achieve high speed and resolution.
The AD678 operates from +5 V and ±12 V supplies and dissipates 560 mW (typ). The AD678 is available in 28-pin plastic DIP, ceramic DIP, and 44 J-leaded ceramic surface mount packages.
Screening to MIL-STD-883C Class B is also available.
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.