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.

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 (see Table 8 of data sheet for address and part number selection). 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 SOT23 and 8 lead MSOP Packages.

Applications

Data Sheet, Rev. 0, 12/07