The AD7991/AD7995/AD7999 are 12-/10-/8-bit, low power, successive approximation ADCs with an I²C compatible interface. Each part operates from a single 2.7 V to 5.5 V power supply and features a 1 μs conversion time. The track-and-hold amplifier allows each part to handle input frequencies of up to 14 MHz, and a multiplexer allows taking samples from four channels.

Each AD7991/AD7995/AD7999 provides a 2-wire serial interface compatible with I²C interfaces. The AD7991 and AD7995 come in two versions and each version has an individual I²C address. This allows two of the same devices to be connected to the same I²C bus. Both versions support standard, fast, and high speed I²C interface modes. The AD7999 comes in one version.

The AD7991/AD7995/AD7999 normally remain in a shutdown state, powering up only for conversions. The conversion process is controlled by a command mode, during which each I²C read operation initiates a conversion and returns the result over the I²C bus.

When four channels are used as analog inputs, the reference for the part is taken from V_DD; this allows the widest dynamic input range to the ADC. Therefore, the analog input range to the ADC is 0 V to V_DD. An external reference, applied through the V_IN3/V_REF input, can also be used with this part.

Product Highlights

1. Four single-ended analog input channels, or three single-ended analog input channels and one reference input channel.
2. I²C compatible serial Interface. Standard, Fast and Hs-Modes
3. Automatic shutdown.
4. Reference derived from the power supply or external reference.
5. 8-lead SOT-23 Package.

Applications

System Monitoring

Battery Powered Systems

Data Acquisition

Medical Instruments

Data Sheet, Rev. 0, 12/07

The model number is a specific version of a generic that can be purchased or sampled.

Status indicates the current lifecycle of the product. This can be one of 4 stages:

• Pre-Release: The model has not been released to general production, but samples may be available.
• Production: The model is currently being produced, and generally available for purchase and sampling.
• Last Time Buy: The model has been scheduled for obsolescence, but may still be purchased for a limited time.
• Obsolete: The specific part is obsolete and no longer available. Other models listed in the table may still be available (if they have a status that is not obsolete).

The package for this IC (i.e. DIP, SOIC, BGA). An Evaluation Board is a board engineered to show the performance of the model, the part is included on the board.

For detailed drawings and chemical composition please consult our  Package Site

Pin Count is the number of pins, balls, or pads on the device. Pin-out diagrams & pin function descriptions may be found in the datasheet.

This is the acceptable operating range of the device. The various ranges specified are as follows:

• Commercial: 0 to +70 degrees Celsius
• Military : -55 to +125 degrees Celsius
• Industrial: Temperature ranges may vary by model. Please consult the datasheet for more information.
• Automotive: -40 to +125 degrees Celsius

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.

This is the date Analog Devices, Inc. anticipates that the product will ship from the warehouse. Most orders ship within 48 hours of this date.Once an order has been placed, Analog Devices, Inc. will send an Order Acknowledgement email to confirm your delivery date. It is important to note the scheduled dock date on the order entry screen. We do take orders for items that are not in stock, so delivery may be scheduled at a future date. Also, please note the warehouse location for the product ordered. We have warehouses in the United States, Europe and Southeast Asia. Transit times from these sites may vary.

Due to environmental concerns, ADI offers many of our products in lead-free versions. For more information about lead-free parts, please consult our Pb (Lead) free information page.