Features and Benefits
- Complete 8-Bit Signal Conditioning A/D Converter Including Instrumentation Amp and Reference
- Microprocessor Bus Interface
- 10 µs Conversion Speed
- Flexible Input Stage: Instrumentation Amp Front End Provides Differential Inputs and High Common-Mode Rejection
- No User Trims Required
- No Missing Codes Over Temperature
- Single +5 V Supply Operation
- Convenient Input Ranges
- 20-Pin DIP or Surface-Mount Package
- Low Cost Monolithic Construction
- MIL-STD-883B Compliant Versions Available
The AD670 is a complete 8-bit signal conditioning analog-to-digital converter. It consists of an instrumentation amplifier front end along with a DAC, comparator, successive approximation register (SAR), precision voltage reference, and a three-state output buffer on a single monolithic chip. No external components or user trims are required to interface, with full accuracy, an analog system to an 8-bit data bus. The AD670 will operate on the +5 V system supply. The input stage provides differential inputs with excellent common-mode rejection and allows direct interface to a variety of transducers.
The device is configured with input scaling resistors to permit two input ranges: 0 mV to 255 mV (1 mV/LSB) and 0 to 2.55 V (10 mV/LSB). The AD670 can be configured for both unipolar and bipolar inputs over these ranges. The differential inputs and common-mode rejection of this front end are useful in applications such as conversion of transducer signals superimposed on common-mode voltages.
The AD670 incorporates advanced circuit design and proven processing technology. The successive approximation function is implemented with I2L (integrated injection logic). Thin-film SiCr resistors provide the stability required to prevent missing codes over the entire operating temperature range while laser wafer trimming of the resistor ladder permits calibration of the device to within ±1 LSB. Thus, no user trims for gain or offset are required. Conversion time of the device is 10 µs.
The AD670 is available in four package types and five grades. The J and K grades are specified over 0°C to +70°C and come in 20-pin plastic DIP packages or 20-terminal PLCC packages. The A and B grades (-40°C to +85°C) and the S grade (-55°C to +125°C) come in 20-pin ceramic DIP packages.
The S grade is also available with optional processing to MIL-STD-883 in 20-pin ceramic DIP or 20-terminal LCC packages. The Analog Devices Military Products Databook should be consulted for detailed specifications.
Product Lifecycle Not Recommended for New Designs
This designates products ADI does not recommend broadly for new designs.
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.