Datasheet

SDA

SCL

C Serial Interface

Conversion Result

Pointer = 00000000

Pointer

(selects

read from

or write to)

Pointer Address

Highest Conversion

Pointer = 00000111

Lowest Conversion

Pointer = 00000110

Configuration

Pointer = 00000010

Alert Status

Pointer = 00000001

Hysteresis

Pointer = 00000101

High Limit

Pointer = 00000100

Low Limit

Pointer = 00000011

Data

ADC081C021, ADC081C027

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SNAS447C –FEBRUARY 2008–REVISED MARCH 2013

POWER-ON RESET

An internal power-on reset (POR) occurs when the supply voltage transitions above the power-on reset

threshold. Each of the registers contains a defined value upon POR and this data remains there until any of the

following occurs:

• The first conversion is completed, causing the Conversion Result and Status registers to be updated.

• A different data word is written to a writeable register.

• The ADC is powered down.

The internal registers will lose their contents if the supply voltage goes below 2.4V. Should this happen, it is

important that the V

supply be lowered to a maximum of 200mV before the supply is raised again to properly

reset the device and ensure that the ADC performs as specified.

INTERNAL REGISTERS

The ADC081C021 has 8 internal data registers and one address pointer. The registers provide additional ADC

functions such as storing minimum and maximum conversion results, setting alert threshold levels, and storing

data to configure the operation of the device. Figure 24 shows all of the registers and their corresponding

address pointer values. All of the registers are read/write capable except the conversion result register which is

read-only.

Figure 24. Register Structure

Product Folder Links: ADC081C021 ADC081C027