Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsData collecting ICsData acquisition IC - AD converter (ADC) External VSSOP 8

SAR

Serial

Interface

Comparator

ADS8326

S/HAmp

DCLOCK

OUT

CS/SHDN

+IN

REF

-IN

CDAC

ADS8326

www.ti.com

.................................................................................................................................................. SBAS343C –MAY 2007–REVISED SEPTEMBER 2009

16-Bit, High-Speed, 2.7V to 5.5V microPower Sampling

ANALOG-TO-DIGITAL CONVERTER

Check for Samples: ADS8326

FEATURES

APPLICATIONS

• Battery-Operated Systems

• 16 Bits No Missing Codes (Full-Supply Range,

High or Low Grade)

• Remote Data Acquisition

• Isolated Data Acquisition

• Very Low Noise: 3LSB

• Simultaneous Sampling, Multichannel

• Excellent Linearity:

Systems

±1LSB typ, ±1.5LSB max INL

• Industrial Controls

±0.6LSB typ, ±1LSB max DNL

±1mV max Offset

• Robotics

±12LSB typ Gain Error

• Vibration Analysis

• microPower:

DESCRIPTION

10mW at 5V, 250kHz

4mW at 2.7V, 200kHz

The ADS8326 is a 16-bit, sampling, analog-to-digital

2mW at 2.7V, 100kHz

(A/D) converter specified for a supply voltage range

0.2mW at 2.7V, 10kHz

from 2.7V to 5.5V. It requires very little power, even

when operating at the full data rate. At lower data

• MSOP-8 and SON-8 Packages

rates, the high speed of the device enables it to

(SON-8 package same as 3x3 QFN)

spend most of its time in the power-down mode. For

• 16-Bit Upgrade to the 12-Bit ADS7816 and

example, the average power dissipation is less than

ADS7822

0.2mW at a 10kHz data rate.

• Pin-Compatible with the ADS7816, ADS7822,

The ADS8326 offers excellent linearity and very low

ADS7826, ADS7827, ADS7829, ADS8320, and

noise and distortion. It also features a synchronous

ADS8325

serial (SPI/SSI-compatible) interface and a differential

• Serial ( SPI™/SSI) Interface

input. The reference voltage can be set to any level

within the range of 0.1V to V

Low power and small size make the ADS8326 ideal

for portable and battery-operated systems. It is also a

perfect fit for remote data-acquisition modules,

simultaneous multichannel systems, and isolated

data acquisition. The ADS8326 is available in either

an MSOP-8 and an SON-8 package.

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.

2SPI is a trademark of Motorola, Inc.

3All other 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 (38 pages)

PAGE 1
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 16-Bit, High-Speed, 2.7V to 5.5V microPower Sampling ANALOG-TO-DIGITAL CONVERTER Check for Samples: ADS8326 FEATURES APPLICATIONS • • • • • 1 23 • • • • • • • 16 Bits No Missing Codes (Full-Supply Range, High or Low Grade) Very Low Noise: 3LSBPP Excellent Linearity: ±1LSB typ, ±1.
PAGE 2
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. 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.
PAGE 3
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 DISSIPATION RATINGS PACKAGE R θ JC R θ JA DERATING FACTOR ABOVE TA = +25°C DGK +39.1°C/W +206.3°C/W 4.847mW/°C 606mW 388mW 315mW DRB +5°C/W +45.8°C/W 3.
PAGE 4
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com ELECTRICAL CHARACTERISTICS: VDD = +5V (continued) At –40°C to +85°C, VREF = +5V, –IN = GND, fSAMPLE = 250kHz, and fDCLOCK = 24 × fSAMPLE, unless otherwise noted.
PAGE 5
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 ELECTRICAL CHARACTERISTICS: VDD = +2.7V At –40°C to +85°C, VREF = +2.5V, –IN = GND, fSAMPLE = 200kHz, and fDCLOCK = 24 × fSAMPLE, unless otherwise noted.
PAGE 6
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com ELECTRICAL CHARACTERISTICS: VDD = +2.7V (continued) At –40°C to +85°C, VREF = +2.5V, –IN = GND, fSAMPLE = 200kHz, and fDCLOCK = 24 × fSAMPLE, unless otherwise noted.
PAGE 7
ADS8326 www.ti.com..................................................................................................................................................
PAGE 8
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.
PAGE 9
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 TIMING INFORMATION (continued) Table 1. Timing Characteristics SYMBOL DESCRIPTION tSMPL Analog input sample time tCONV Conversion time tCYC Complete cycle time MIN TYP 4.5 MAX 5.
PAGE 10
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS: VDD = +5V At TA = +25°C, VDD = +5V, VREF = +5V. fSAMPLE = 250kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 11
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 TYPICAL CHARACTERISTICS: VDD = +5V (continued) At TA = +25°C, VDD = +5V, VREF = +5V. fSAMPLE = 250kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 12
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS: VDD = +5V (continued) At TA = +25°C, VDD = +5V, VREF = +5V. fSAMPLE = 250kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 13
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 TYPICAL CHARACTERISTICS: VDD = +5V (continued) At TA = +25°C, VDD = +5V, VREF = +5V. fSAMPLE = 250kHz, fCLK = 24 × fSAMPLE, unless otherwise noted. SIGNAL-TO-NOISE + DISTORTION vs INPUT LEVEL PEAK-TO-PEAK NOISE FOR A DC INPUT vs REFERENCE VOLTAGE 100 100 Peak-to-Peak Noise (LSB) 90 200 fIN = 1.
PAGE 14
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS: VDD = +5V (continued) At TA = +25°C, VDD = +5V, VREF = +5V. fSAMPLE = 250kHz, fCLK = 24 × fSAMPLE, unless otherwise noted. REFERENCE CURRENT vs SAMPLING RATE POWER-DOWN CURRENT vs TEMPERATURE 30 Power-Down Current (nA) Reference Current (mA) 1000 100 10 1 0.
PAGE 15
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 TYPICAL CHARACTERISTICS: VDD = +2.7V At TA = +25°C, VDD = +2.7V, VREF = +2.5V. fSAMPLE = 200kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 16
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS: VDD = +2.7V (continued) At TA = +25°C, VDD = +2.7V, VREF = +2.5V. fSAMPLE = 200kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 17
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 TYPICAL CHARACTERISTICS: VDD = +2.7V (continued) At TA = +25°C, VDD = +2.7V, VREF = +2.5V. fSAMPLE = 200kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
PAGE 18
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com TYPICAL CHARACTERISTICS: VDD = +2.7V (continued) At TA = +25°C, VDD = +2.7V, VREF = +2.5V. fSAMPLE = 200kHz, fCLK = 24 × fSAMPLE, unless otherwise noted. SIGNAL-TO-NOISE + DISTORTION vs INPUT LEVEL 100 SUPPLY CURRENT vs TEMPERATURE 1.38 fIN = 1.97754kHz, -0.2dB 90 1.
PAGE 19
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 THEORY OF OPERATION The ADS8326 is a classic Successive Approximation Register (SAR) Analog-to-Digital (A/D) converter. The architecture is based on capacitive redistribution that inherently includes a sample-and-hold function. The converter is fabricated on a 0.6μ CMOS process.
PAGE 20
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com ANALOG INPUT 0V to +VREF Peak-to-Peak The analog input of ADS8326 is differential. The +IN and –IN input pins allow for a differential input signal. The amplitude of the input is the difference between the +IN and –IN input, or (+IN) – (–IN).
PAGE 21
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 The input current required by the analog inputs depends on a number of factors: sample rate, input voltage, source impedance, and power-down mode. Essentially, the current into the ADS8326 charges the internal capacitor array during the sample period.
PAGE 22
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com REFERENCE INPUT ADS8326 The external reference sets the analog input range. The ADS8326 operates with a reference in the range of 0.1V to VDD. There are several important implications to this. As the reference voltage is reduced, the analog voltage weight of each digital output code is reduced.
PAGE 23
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 DIGITAL INTERFACE Signal Levels The ADS8326 has a wide range of power-supply voltage. The A/D converter, as well as the digital interface circuit, is designed to accept and operate from 2.7V up to 5.5V. This voltage range will accommodate different logic levels.
PAGE 24
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com 65535 1111 1111 1111 1111 65534 1111 1111 1111 1111 65533 1000 0000 0000 0001 32769 1000 0000 0000 0000 32768 0111 1111 1111 1111 32767 0000 0000 0000 0010 2 0000 0000 0000 0001 1 0000 0000 0000 0000 Step Digital Output Code Straight Binary 1111 1111 1111 1111 0 2.
PAGE 25
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 POWER DISSIPATION Short Cycling The architecture of the converter, the semiconductor fabrication process, and a careful design allow the ADS8326 to convert at up to a 250kHz rate while requiring very little power.
PAGE 26
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com LAYOUT For optimum performance, care should be taken with the physical layout of the ADS8326 circuitry. This is particularly true if the reference voltage is low and/or the conversion rate is high. At a 250kHz conversion rate, the ADS8326 makes a bit decision every 167ns.
PAGE 27
ADS8326 www.ti.com.................................................................................................................................................. SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009 APPLICATION CIRCUITS high-frequency noise from the supply itself. The exact values should be picked such that the filter provides adequate rejection of noise. Operational amplifiers and voltage reference are connected to analog power supply, AVDD.
PAGE 28
ADS8326 SBAS343C – MAY 2007 – REVISED SEPTEMBER 2009.................................................................................................................................................. www.ti.com REVISION HISTORY NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision B (May, 2008) to Revision C .....................................................................................................
PAGE 29
PACKAGE OPTION ADDENDUM www.ti.
PAGE 30
PACKAGE OPTION ADDENDUM www.ti.com 18-Oct-2013 Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
PAGE 31
PACKAGE MATERIALS INFORMATION www.ti.com 6-Nov-2013 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing ADS8326IBDGKR VSSOP DGK 8 SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 2500 330.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 ADS8326IBDGKT VSSOP DGK 8 250 180.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1 ADS8326IBDRBR SON DRB 8 3000 330.0 12.4 3.3 3.3 1.1 8.0 12.
PAGE 32
PACKAGE MATERIALS INFORMATION www.ti.com 6-Nov-2013 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) ADS8326IBDGKR VSSOP DGK 8 2500 367.0 367.0 35.0 ADS8326IBDGKT VSSOP DGK 8 250 210.0 185.0 35.0 ADS8326IBDRBR SON DRB 8 3000 338.1 338.1 20.6 ADS8326IBDRBT SON DRB 8 250 210.0 185.0 35.0 ADS8326IDGKR VSSOP DGK 8 2500 367.0 367.0 35.0 ADS8326IDGKT VSSOP DGK 8 250 210.0 185.0 35.
PAGE 33
PAGE 34
PAGE 35
PAGE 36
PAGE 37
PAGE 38
IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete.