AD7470 Analog Devices, AD7470 Datasheet

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AD7470

Manufacturer Part Number
AD7470
Description
10-Bit, 2.7 V to 5.25 V, 1.75 MSPS Low Power ADC
Manufacturer
Analog Devices
Datasheet

Specifications of AD7470

Resolution (bits)
10bit
# Chan
1
Sample Rate
1.75MSPS
Interface
Par
Analog Input Type
SE-Uni
Ain Range
Uni (Vref)
Adc Architecture
SAR
Pkg Type
SOP

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
AD7470ARUZ
Manufacturer:
ADI/亚德诺
Quantity:
20 000
a
GENERAL DESCRIPTION
The AD7470/AD7472 are 10-bit/12-bit high speed, low power,
successive approximation ADCs. The parts operate from a single
2.7 V to 5.25 V power supply and feature throughput rates up to
1.5 MSPS for the 12-bit AD7472 and up to 1.75 MSPS for the
10-bit AD7470. The parts contain a low noise, wide bandwidth
track-and-hold amplifier that can handle input frequencies in
excess of 1 MHz.
The conversion process and data acquisition are controlled
using standard control inputs, allowing easy interfacing to
microprocessors or DSPs. The input signal is sampled on the
falling edge of CONVST, and conversion is also initiated at
this point. BUSY goes high at the start of conversion and
goes low 531.66 ns after falling edge of CONVST (AD7472
with a clock frequency of 26 MHz) to indicate that the con-
version is complete. There are no pipeline delays associated
with the parts. The conversion result is accessed via standard
CS and RD signals over a high speed parallel interface.
The AD7470/AD7472 use advanced design techniques to
achieve very low power dissipation at high throughput rates. With
3 V supplies and 1.5 MSPS throughput rates, the AD7470
typically consumes, on average, just 1.1 mA. With 5 V supplies
and 1.75 MSPS, the average current consumption is typically
1.6 mA. The part also offers flexible power/throughput rate
management. Operating the AD7470 with 3 V supplies and
500 kSPS throughput reduces the current consumption to 713 µA.
At 5 V supplies and 500 kSPS, the part consumes 944 µA.
REV. B
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
FEATURES
Specified for V
1.75 MSPS for AD7470 (10-Bit)
1.5 MSPS for AD7472 (12-Bit)
Low Power
Wide Input Bandwidth
70 dB Typ SNR at 500 kHz Input Frequency
Flexible Power/Throughput Rate Management
No Pipeline Delays
High Speed Parallel Interface
Sleep Mode: 50 nA Typ
24-Lead SOIC and TSSOP Packages
AD7470: 3.34 mW Typ at 1.5 MSPS with 3 V Supplies
AD7472: 3.54 mW Typ at 1.2 MSPS with 3 V Supplies
7.97 mW Typ at 1.75 MSPS with 5 V Supplies
8.7 mW Typ at 1.5 MSPS with 5 V Supplies
DD
of 2.7 V to 5.25 V
It is also possible to operate the parts in an auto sleep mode,
where the part wakes up to do a conversion and automatically
enters sleep mode at the end of conversion. This method allows
very low power dissipation numbers at lower throughput rates.
In this mode, the AD7472 can be operated with 3 V supplies at
100 kSPS, and consume an average current of just 124 µA. At
5 V supplies and 100 kSPS, the average current consumption is
171 µA.
The analog input range for the part is 0 V to REF IN. The 2.5 V
reference is applied externally to the REF IN pin. The conver-
sion rate is determined by the externally-applied clock.
PRODUCT HIGHLIGHTS
1. High Throughput with Low Power Consumption. The
2. Flexible Power/Throughput Rate Management. The conver-
3. No Pipeline Delay. The part features a standard successive
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
Fax: 781/326-8703
CONVST
AD7470 offers 1.75 MSPS throughput and the AD7472
offers 1.5 MSPS throughput rates with 4 mW power
consumption.
sion rate is determined by an externally-applied clock allow-
ing the power to be reduced as the conversion rate is reduced.
The part also features an auto sleep mode to maximize power
efficiency at lower throughput rates.
approximation ADC with accurate control of the sampling
instant via a CONVST input and once off conversion control.
V
IN
10-Bit/12-Bit Parallel ADCs
AD7470 IS A 10-BIT PART WITH DB0 TO DB9 AS OUTPUTS.
AD7472 IS A 12-BIT PART WITH DB0 TO DB11 AS OUTPUTS.
AD7470/AD7472
AV
FUNCTIONAL BLOCK DIAGRAM
DD
T/H
DV
© 2003 Analog Devices, Inc. All rights reserved.
DD
APPROXIMATION
SUCCESSIVE
CONTROL
10-/12-BIT
LOGIC
REF IN
ADC
AD7470/AD7472
AGND
1.75 MSPS, 4 mW
DGND
DRIVERS
OUTPUT
V
DRIVE
www.analog.com
DB9 (DB11)
DB0
CLK IN
CS
BUSY
RD

Related parts for AD7470

AD7470 Summary of contents

Page 1

... CONVST LOGIC AD7470/AD7472 AGND AD7470 IS A 10-BIT PART WITH DB0 TO DB9 AS OUTPUTS. AD7472 IS A 12-BIT PART WITH DB0 TO DB11 AS OUTPUTS also possible to operate the parts in an auto sleep mode, where the part wakes conversion and automatically enters sleep mode at the end of conversion. This method allows very low power dissipation numbers at lower throughput rates ...

Page 2

... The AD7470 functionally works at 2.35 V. Typical specifications @ 25°C for SNR (100 kHz dB; THD (100 kHz) = –84 dB; INL ± 0.8 LSB The AD7470 will typically maintain A-grade performance up to 125°C, with a reduced CLK of 20 MHz @ 5 V and 16 MHz @ 3 V. Typical sleep mode current @ 125°C is 700 nA. 4 Sample tested @ 25°C to ensure compliance. ...

Page 3

... Straight (Natural) Binary 135 135 135 1.2 1.5 1.2 +2.7/+5.25 2.4 900 1.5 800 –3– AD7470/AD7472 = 26 MHz @ 5 V and CLKIN unless otherwise noted.) MAX Unit Test Conditions/Comments f = 1.5 MSPS @ 1.2 MSPS @ typ f = 500 kHz Sine Wave IN dB min f = 100 kHz Sine Wave IN ...

Page 4

... AD7470/AD7472 AD7472–SPECIFICATIONS Parameter DYNAMIC PERFORMANCE Signal to Noise + Distortion (SINAD) Signal-to-Noise Ratio (SNR) Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) Intermodulation Distortion (IMD) Second-Order Terms Third-Order Terms Aperture Delay Aperture Jitter Full Power Bandwidth DC ACCURACY Resolution Integral Nonlinearity ...

Page 5

... OUTPUT PIN C L 50pF 200 –5– AD7470/AD7472 unless otherwise noted.) MIN MAX Description t = 1/f CLK CLK IN Wake-Up Time CONVST Pulse Width CONVST to BUSY Delay and B Versions Version ...

Page 6

... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD7470/AD7472 features proprietary ESD protection circuitry, permanent dam- age may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . 150° ...

Page 7

... REF IN Reference Input. An external reference must be applied to this input. The voltage range for the external reference is 2.5 V ± 1% for specified performance. AV Analog Supply Voltage, 2 5.25 V. This is the only supply voltage for all analog circuitry on the AD7470/ DD AD7472. The AV DD apart even on a transient basis. This supply should be decoupled to AGND. ...

Page 8

... V logic. DB0–DB9/11 Data Bit 0 to Data Bit 9 (AD7470) and DB11 (AD7472). Parallel digital outputs that provide the conversion result for the part. These are three-state outputs that are controlled by CS and RD. The output high voltage level for these ...

Page 9

... The last transition should occur at the analog value 1.5 LSB below the nominal full scale. The first transition is a 0.5 LSB above the low end of the scale (zero in the case of AD7470/ AD7472). The gain error is the deviation of the actual difference between the first and last code transitions from the ideal differ- ence between the first and last code transitions with offset errors removed ...

Page 10

... The CS and RD lines are then activated in parallel to read the 10- or 12-data bits. The recom- mended REF IN voltage is 2.5 V providing an analog input range 2.5 V, making the AD7470/AD7472 a unipolar ADC recommended to perform a dummy conversion after power-up as the first conversion result could be incorrect. This COMPARATOR also ensures that the part is in the correct mode of operation ...

Page 11

... CLOCK SOURCES The max CLK specification for the AD7470 is 30 MHz, and for the AD7472 MHz. These frequencies are not standard off-the-shelf oscillator frequencies. Many manufacturers pro- duce oscillator modules close to these frequencies; a typical one being 25.175 MHz from IQD Limited. AEL Crystals Limited produces a 25 MHz oscillator module in various packages ...

Page 12

... AD7470/AD7472 PARALLEL INTERFACE The parallel interfaces of the AD7470 and AD7472 are 10 bits and 12 bits wide, respectively. The output data buffers are acti- vated when both CS and RD are logic low. At this point, the con- tents of the data register are placed onto the data bus. Figure 10 shows the timing diagram for the parallel port ...

Page 13

... V supply, the V DRIVE The ADC has better dynamic performance than operating the part while still being able to interface parts, pushes the AD7470/AD7472 to the top bracket of high performance 10-bit/12-bit ADCs. Of course, the ADC can have its V and DV DRIVE ered from supply ...

Page 14

... AD7470/AD7472 Mode 1 Figure 14 shows the AD7472 conversion sequence in Mode 1 using a throughput rate of 500 kSPS and a clock frequency of 26 MHz supply, the current consumption for the part when converting is typically 2 mA, and the quiescent current is typically 650 µA. The conversion time of 531.66 ns contributes 2.658 mW to the overall power dissipation in the following way: (531.66 ns/2 µ ...

Page 15

... TPC 2. Power vs. Throughput (Mode and 3 V) 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 512 1024 1536 2048 2560 CODE TPC 3. Typical INL for 2. ° C Typical Performance Characteristics–AD7470/AD7472 –0.2 –0.4 –0.6 –0.8 –1.0 1100 1300 1500 600 650 700 750 3072 3584 4096 1.0 0.8 0.6 0.4 ...

Page 16

... AD7470/AD7472 70.6 70.4 –40 C +25 C 70.2 70.0 69.8 69.6 69.4 69.2 2.50 2.75 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 SUPPLY (V) TPC 7. Typical SNR vs. Supply 0 –20 –40 –60 –80 –100 –120 0 100 200 300 FREQUENCY (kHz) TPC 8. Typical SNR @ 500 kHz Input Tone 0.2 –0.3 –0.8 –1.3 +85 C –1.8 –2.3 –2.8 –3.3 –3.8 10 400 500 600 –16– ...

Page 17

... AD7470/ AD7472 should use as large a trace as possible to provide a low impedance path and reduce the effects of glitches on the power supply line ...

Page 18

... PORTC and PORTD of the microcontroller are AD7470/ bidirectional and used to address the AD7470/AD7472 and also AD7472* to read in the 10-bit (AD7470) or 12-bit (AD7472) data. The OE pin on the PIC can be used to enable the output buffers on the AD7470/AD7472 and to perform a read operation. CS ...

Page 19

... CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN (RU-24) Dimensions shown in millimeters 7.90 7.80 7. 4.50 4.40 4.30 6.40 BSC 1 12 0.65 1.20 BSC MAX 0.30 0.20 SEATING 0.19 PLANE 0.09 0.10 COPLANARITY COMPLIANT TO JEDEC STANDARDS MO-153AD –19– AD7470/AD7472 0.75 (0.0295) 45 0.25 (0.0098 1.27 (0.0500) 0.40 (0.0157) 0. 0.60 0.45 ...

Page 20

... AD7470/AD7472 Revision History Location 10/03—Data Sheet changed from REV REV. B. Added Y version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Universal Changes to SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Changes to TIMING SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Changes to ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Changes to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Changes to PIN FUNCTION DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Changes to Offset Error description Changes to Gain Error description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Changes to OPERATING MODES section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Changes to POWER-UP section ...

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