AD7992

a

REV. PrH

09/03

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Analog Devices, Inc., 200

3

Interfacein10-LeadMSOP

Preliminary Technical Data

PRELIMINARYTECHNICAL DATA

FUNCTIONAL BLOCK DIAGRAM

FEATURES

12-Bit ADC with Fast Conversion Time: 2

µµµµµs

Two Single-Ended Analog Input Channels

Low Power Consumption

Fast Throughput Rate:- 188 KSPS

Sequencer Operation

Automatic Cycle Mode

Standard, Fast, and High-Speed Modes

Out of Range Indicator/ALERT Function

Pin-Selectable Addressing via AS

Two Versions Allow Five I

10-Lead MSOP Package

GENERAL DESCRIPTION

The AD7992 is a 12-bit, high speed, low power, succes-

sive-approximation ADC. The part operates from a single

2.7 V to 5.5 V power supply and features a conversion

time of 2

µs. The part contains a two channel multiplexer

and track/hold amplifier which can handle input frequen-

cies in excess of TBD kHz.

The AD7992 provides a two-wire serial interface which is

compatible with I

versions, AD7992-0, and AD7992-1. Each version allows

for a minimum of two different I

AD7992-0 supports Standard and Fast I

Modes, while the AD7992-1 supports Standard, Fast, and

two High-Speed I

The AD7992 normally remains in a power-down state

while not converting, powering up only to perform con-

versions. The conversion process can be controlled using

the

CONVST pin, an Automatic Conversion Cycle se-

lected through software control, or a mode where conver-

sions occur across read Address operations. The AD7992

uses advanced design techniques to achieve low power

dissipation with a fast conversion time. There are no pipe-

line delays associated with the part.

The reference for the part is applied externally and can be

namic input range to the ADC.

On-chip registers can be programmed with high and low

limits for the conversion result, and an open drain Out of

Range Indicator output (ALERT), becomes active when

the programmed high or low limits are violated. This

output can be used as an interrupt.

PRODUCT HIGHLIGHTS

1. 2

µs Conversion time with low power consumption.

2. I

addresses. Two AD7992 versions allow five

AD7992 devices to be connected to the same serial bus.

3. The part features automatic shutdown while not convert-

ing to maximize power efficiency. Current consumption

is 1

µA max when in shutdown.

4. Reference can be driven up to the power supply.

5. Out of Range Indicator which can be software disabled/

enabled.

6. Oneshot and automatic conversion rates.

7. No Pipeline Delay

The part features a standard successive-approximation

ADC.

SMBus is a trademark and I

T/H

VIN1

12-BIT SUCCESSIVE

APPROXIMATION

ADC

CONTROL

LOGIC

I/P

MUX

VIN2/REFIN

AD7992

VDD

SCL

I2C INTERFACE

DATAHIGH LIMIT

REGISTER CH1

DATALOW LIMIT

REGISTER CH1

CONVERSION

RESULT REGISTER

CONFIGURATION

REGISTER

DATALOW LIMIT

REGISTER CH0

DATAHIGH LIMIT

REGISTER CH0

CYCLE TIMER

REGISTER

ALERT STATUS

REGISTER

SDA

GND

ALERT

CONVST

GND

AS

OSCILLATOR

HYSTERESIS

REGISTER CH0

HYSTERESIS

REGISTER CH1

Part Number

No. of Bits

No. of Channels

Package

AD7998

1 2

8

20

TSSOP

AD7994

1 2

4

16

TSSOP

AD7997

1 0

8

20

TSSOP

AD7993

1 0

4

16

TSSOP

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