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AD7453

Pseudo Differential, 555 kSPS,

12-Bit ADC in an 8-Lead SOT-23

FEATURES

Low Power at Max Throughput Rate:

Pseudo Differential Analog Input

Wide Input Bandwidth:

70 dB SINAD at 100 kHz Input Frequency

Flexible Power/Serial Clock Speed Management

No Pipeline Delays

MICROWIRE™/DSP Compatible

Power-Down Mode: 1

A Max

8-Lead SOT-23 Package

APPLICATIONS

Transducer Interface

Battery-Powered Systems

Data Acquisition Systems

Portable Instrumentation

Motor Control

Communications

FUNCTIONAL BLOCK DIAGRAM

T/H

CONTROL LOGIC

12-BIT

SUCCESSIVE

APPROXIMATION

ADC

GND

SCLK

SDATA

CS

AD7453

GENERAL DESCRIPTION

The AD7453 is a 12-bit, high speed, low power, successive

approximation (SAR) analog-to-digital converter that features a

pseudo differential analog input. This part operates from a

single 2.7 V to 5.25 V power supply and features throughput

rates up to 555 kSPS.

The part contains a low noise, wide bandwidth, differential

track-and-hold amplifier (T/H) that can handle input frequen-

cies in excess of 1 MHz. The reference voltage for the AD7453

100 mV to 3.5 V, depending on the power supply and what

suits the application.

The conversion process and data acquisition are controlled

using

CS and the serial clock, allowing the device to interface

with microprocessors or DSPs. The input signals are sampled

on the falling edge of

CS; the conversion is also initiated at

this point.

The SAR architecture of this part ensures that there are no

pipeline delays.

The AD7453 uses advanced design techniques to achieve very

low power dissipation.

PRODUCT HIGHLIGHTS

1. Operation with 2.7 V to 5.25 V Power Supplies.

2. High Throughput with Low Power Consumption.

With a 3 V supply, the AD7453 offers 3.3 mW max power

consumption for a 555 kSPS throughput rate.

3. Pseudo Differential Analog Input.

4. Flexible Power/Serial Clock Speed Management.

The conversion rate is determined by the serial clock, allow-

ing the power to be reduced as the conversion time is reduced

through the serial clock speed increase. This part also features

a shutdown mode to maximize power efficiency at lower

throughput rates.

5. Variable Voltage Reference Input.

6. No Pipeline Delay.

7. Accurate control of the sampling instant via a

CS input and

once-off conversion control.

8. ENOB > 10-bits Typically with 500 mV Reference.