Pseudo Differential, 555 kSPS,
12-Bit ADC in an 8-Lead SOT-23
AD7453
FEATURES
FUNCTIONAL BLOCK DIAGRAM
Specified for VDD of 2.7 V to 5.25 V
Low Power at Max Throughput Rate:
3.3 mW Max at 555 kSPS with VDD = 3 V
7.25 mW Max at 555 kSPS with VDD = 5 V
Pseudo Differential Analog Input
Wide Input Bandwidth:
70 dB SINAD at 100 kHz Input Frequency
Flexible Power/Serial Clock Speed Management
No Pipeline Delays
V
DD
V
12-BIT
SUCCESSIVE
APPROXIMATION
ADC
IN+
T/H
V
IN–
V
REF
High Speed Serial Interface—SPI®/QSPI™/
MICROWIRE™/DSP Compatible
Power-Down Mode: 1 A Max
8-Lead SOT-23 Package
SCLK
SDATA
CS
AD7453
CONTROL LOGIC
APPLICATIONS
Transducer Interface
Battery-Powered Systems
Data Acquisition Systems
Portable Instrumentation
Motor Control
GND
Communications
GENERAL DESCRIPTION
PRODUCT HIGHLIGHTS
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.
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.
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
is applied externally to the VREF pin and can range from
100 mV to 3.5 V, depending on the power supply and what
suits the application.
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.
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.
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.
The SAR architecture of this part ensures that there are no
pipeline delays.
8. ENOB > 10-bits Typically with 500 mV Reference.
The AD7453 uses advanced design techniques to achieve very
low power dissipation.
REV. 0
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