Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsData collecting ICsData acquisition IC - AD converter (ADC) External , Internal TQFP 32

SAR

OutputLatches

and

3-State

Drivers

Comparator

ADS8322

S/HAmp

BYTE

Parallel

Data

Output

+IN

-IN

CDAC

REF

Conversion

andControl

Logic

Internal

+2.5VRef

CONVST

CLOCK

BUSY

REF

OUT

ADS8322

www.ti.com

SBAS215A –JULY 2001–REVISED JANUARY 2010

16-Bit, 500kHz, MicroPower Sampling

ANALOG-TO-DIGITAL CONVERTER

Check for Samples: ADS8322

FEATURES

DESCRIPTION

• HIGH-SPEED PARALLEL INTERFACE

• 500kHz SAMPLING RATE

The ADS8322 is a 16-bit, 500kHz analog-to-digital

(A/D) converter with an internal 2.5V reference. The

• LOW POWER: 85mW at 500kHz

device includes a 16-bit capacitor-based successive

• INTERNAL 2.5V REFERENCE

approximation register (SAR) A/D converter with

• UNIPOLAR INPUT RANGE

inherent sample-and-hold. The ADS8322 offers a full

16-bit interface, or an 8-bit option where data are

• TQFP-32 PACKAGE

read using two read cycles and eight pins. The

ADS8322 is available in a TQFP-32 package and is

APPLICATIONS

ensured over the industrial –40°C to +85°C

• CT SCANNERS

temperature range.

• HIGH-SPEED DATA ACQUISITION

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• TEST AND INSTRUMENTATION

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• MEDICAL EQUIPMENT

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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

2All trademarks are the property of their respective owners.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.

Summary of content (19 pages)

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ADS8322 www.ti.com SBAS215A – JULY 2001 – REVISED JANUARY 2010 16-Bit, 500kHz, MicroPower Sampling ANALOG-TO-DIGITAL CONVERTER Check for Samples: ADS8322 FEATURES 1 • • • • • • 2 DESCRIPTION HIGH-SPEED PARALLEL INTERFACE 500kHz SAMPLING RATE LOW POWER: 85mW at 500kHz INTERNAL 2.5V REFERENCE UNIPOLAR INPUT RANGE TQFP-32 PACKAGE The ADS8322 is a 16-bit, 500kHz analog-to-digital (A/D) converter with an internal 2.5V reference.
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ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure.
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ADS8322 www.ti.com SBAS215A – JULY 2001 – REVISED JANUARY 2010 ELECTRICAL CHARACTERISTICS: +VA = +5V At –40°C to +85°C, +VA = +5V, VREF = +2.5V, fSAMPLE = 500kHz, and fCLK = 20 • fSAMPLE, unless otherwise specified. ADS8322YB (1) ADS8322Y PARAMETER TEST CONDITIONS MIN TYP MAX MIN TYP MAX UNIT RESOLUTION Resolution 16 16 Bits ANALOG INPUTS Full-scale input span (2) Absolute input range +IN – (–IN) 0 +2VREF 0 +2VREF V +IN –0.1 VA + 0.1 –0.1 VA + 0.1 V –IN –0.1 +0.5 –0.1 +0.
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ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com ELECTRICAL CHARACTERISTICS: +VA = +5V (continued) At –40°C to +85°C, +VA = +5V, VREF = +2.5V, fSAMPLE = 500kHz, and fCLK = 20 • fSAMPLE, unless otherwise specified. ADS8322YB (1) ADS8322Y PARAMETER TEST CONDITIONS MIN TYP MAX MIN TYP MAX UNIT DIGITAL INPUT/OUTPUT Logic family CMOS CMOS Logic levels: VIH IIH ≤ +5μA 3.0 +VA 3.0 +VA V VIL IIL ≤ +5μA –0.3 0.8 –0.3 0.8 V VOH IOH = 2 TTL Loads 4.
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ADS8322 www.ti.
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ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com TIMING INFORMATION t1 t3 t2 CLOCK 2 1 Acquisition 3 4 5 17 18 19 Conversion Acquisition tCONV tACQ 20 1 2 3 4 17 18 19 20 t5 t4 CONVST t6 t9 t10 BUSY t7 t11 BYTE t8 t12 CS t13 t18 t14 t15 RD t16 t17 t19 DB15-D8 Bits 15-8 Bits 15-8 FF DB7-D0 Bits 7-0 Bits 7-0 Bits 15-8 TIMING CHARACTERISTICS (1) (2) All specifications typical at –40°C to +85°C, +VD = +5V.
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ADS8322 www.ti.com SBAS215A – JULY 2001 – REVISED JANUARY 2010 TYPICAL CHARACTERISTICS At –40°C to +85°C, +VA = +5V, VREF = +2.5V, fSAMPLE = 500kHz, and fCLK = 20 • fSAMPLE, unless otherwise specified. FREQUENCY SPECTRUM (4096 Point FFT; fIN = 100.1kHz, –0.2dB) SIGNAL-TO-NOISE RATIO AND SIGNAL-TO-NOISE + DISTORTION vs INPUT FREQUENCY 0 90 SNR, SINAD (dB) Amplitude (dB) -30 -60 -90 85 SNR 80 SINAD -120 -150 75 0 20 40 60 80 100 120 140 160 Frequency (Hz) 1 180 200 10 Figure 1. 0.
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ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com TYPICAL CHARACTERISTICS (continued) At –40°C to +85°C, +VA = +5V, VREF = +2.5V, fSAMPLE = 500kHz, and fCLK = 20 • fSAMPLE, unless otherwise specified. DL– vs TEMPERATURE OFFSET ERROR vs TEMPERATURE 0.05 2.5 2.0 0 Deltas (LSB) Deltas (LSB) 1.5 -0.05 -0.10 -0.15 1.0 0.5 0 -0.5 -0.20 -1.0 -0.25 -1.5 -40 0 -20 20 40 60 80 100 -40 -20 0 20 40 60 80 100 60 80 100 Temperature (°C) Temperature (°C) Figure 7. Figure 8.
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ADS8322 www.ti.com SBAS215A – JULY 2001 – REVISED JANUARY 2010 THEORY OF OPERATION The ADS8322 is a high-speed successive approximation register (SAR) A/D converter with an internal 2.5V bandgap reference. The architecture is based on capacitive redistribution, which inherently includes a sample-and-hold function. The basic operating circuit for the ADS8322 is shown in Figure 13. times are at least 40ns and the clock period is at least 100ns.
PAGE 10
ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com REFERENCE Under normal operation, the REFOUT pin should be directly connected to the REFIN pin to provide an internal +2.5V reference to the ADS8322. The ADS8322 can operate, however, with an external reference in the range of 1.5V to 2.6V for a corresponding full-scale range of 3.0V to 5.2V. The internal reference of the ADS8322 is double-buffered.
PAGE 11
ADS8322 www.ti.com SBAS215A – JULY 2001 – REVISED JANUARY 2010 BYTE AVERAGING The output data appear as a full 16-bit word on DB15- DB0 (MSB-LSB), if BYTE is low. The result may also be read on an 8-bit bus by using only DB7-DB0. In this case two reads are necessary. The first read proceeds as before, leaving BYTE low and reading the eight least significant bits on DB7-DB0, then bringing BYTE high. When BYTE is high, the upper eight bits (D15-D8) appear on DB7-DB0.
PAGE 12
ADS8322 SBAS215A – JULY 2001 – REVISED JANUARY 2010 www.ti.com The AGND and DGND pins should be connected to a clean ground point. In all cases, this point should be the analog ground. Avoid connections which are too close to the grounding point of a microcontroller or digital signal processor. If required, run a ground trace directly from the converter to the power supply entry point. The ideal layout will include an analog ground plane dedicated to the converter and associated analog circuitry.
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PACKAGE OPTION ADDENDUM www.ti.
PAGE 14
PACKAGE OPTION ADDENDUM www.ti.com 21-May-2010 In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
PAGE 15
PACKAGE MATERIALS INFORMATION www.ti.com 14-Jul-2012 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant ADS8322Y/250 TQFP PBS 32 250 330.0 16.4 7.2 7.2 1.5 12.0 16.0 Q2 ADS8322Y/2K TQFP PBS 32 2000 330.0 16.4 7.2 7.2 1.5 12.0 16.0 Q2 ADS8322YB/250 TQFP PBS 32 250 330.0 16.4 7.2 7.2 1.5 12.0 16.
PAGE 16
PACKAGE MATERIALS INFORMATION www.ti.com 14-Jul-2012 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) ADS8322Y/250 TQFP PBS ADS8322Y/2K TQFP PBS 32 250 367.0 367.0 38.0 32 2000 367.0 367.0 38.0 ADS8322YB/250 TQFP PBS 32 250 367.0 367.0 38.
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