Datasheet

ManualsBrandsTEXAS INSTRUMENTS ManualsData collecting ICsData acquisition IC - AD converter (ADC) External , Internal SOIC 16

FEATURES APPLICATIONS

DESCRIPTION

Successive Approximation Register

Clock

Comparator

CDAC

Buffer

REF

BUF

8kΩ

Internal

+2.5 V Ref

4kΩ

Serial

Data

Out

and

Control

BUSYBUSY

DATACLK

40kΩ

EXT/INT

PWRD

SDATA

CONV

CAP

20kΩ

ADS8513

www.ti.com

...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009

16-Bit, 40kSPS, Low-Power Sampling ANALOG-TO-DIGITAL CONVERTER

with Internal Reference and Parallel/Serial Interface

• Industrial Process Control

• 40kSPS Minimum Sampling Rate

• Test Equipment

• Very Low Power: 24mW Typ

• Robotics

• ± 3.33V, ± 5V, ± 10V, 4V, and 10V Input Ranges

• DSP Servo Control

• 89dB SNR with 10kHz Input

• Medical Instrumentation

• ± 2LSB Max INL

• Portable Data Acquisition Systems

• – 1/+2LSB Max DNL, 16-Bit NMC

• ± 10mV BPZ, ± 2.5ppm/ ° C BPZ Drift

• 89dB Min SINAD, 102dB Min SFDR

The ADS8513 is a complete low-power, single 5V

• Uses Internal or External 2.5V Reference

supply, 16-bit sampling analog-to-digital (A/D)

converter. It contains a complete 16-bit

• No External Calibration Resistors Required

capacitor-based, successive approximation register

• Single 5V Analog Supply:

(SAR) A/D converter with sample and hold, clock,

– 32.5mW Max Power Dissipation

reference, and serial data interface. The converter

– 50 µ W Max Power-Down Mode

can be configured for a variety of input ranges

including ± 10V, ± 5V, 0V to 10V, and 0.5V to 4.5V. A

• SPI™-Compatible Serial Port up to 20MHz,

high-impedance, 0.3V to 2.8V input is also available

with Master/Slave Feature

with input impedance greater than 10M Ω . For most

• Global CONV and 3-Stated Bus for Multi-Chip

input ranges, the input voltage can swing to 25V or

Simultaneous S/H Operation

– 25V without damage to the converter.

• Pin-Compatible with 16-Bit ADS7813 and

An SPI-compatible serial interface allows data to be

12-Bit ADS7812 and ADS8512

synchronized to an internal or external clock. The

• SO-16 Package

ADS8513 is specified at 40kSPS sampling rate over

the – 40 ° C to +85 ° C industrial temperature range.

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.

2 SPI, QSPI are trademarks of Motorola, Inc.

3 All 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 (33 pages)

PAGE 1
ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 16-Bit, 40kSPS, Low-Power Sampling ANALOG-TO-DIGITAL CONVERTER with Internal Reference and Parallel/Serial Interface FEATURES APPLICATIONS • • • • • • • • • • • • • • • • • 1 23 • • • • 40kSPS Minimum Sampling Rate Very Low Power: 24mW Typ ±3.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates.
PAGE 3
ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ELECTRICAL CHARACTERISTICS (continued) At TA = –40°C to +85°C, fS = 40kSPS, VS = 5V, and using internal reference and fixed resistors, unless otherwise specified.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com ELECTRICAL CHARACTERISTICS (continued) At TA = –40°C to +85°C, fS = 40kSPS, VS = 5V, and using internal reference and fixed resistors, unless otherwise specified. ADS8513I PARAMETER TEST CONDITIONS MIN TYP ADS8513IB MAX MIN TYP MAX UNIT V DIGITAL INPUTS VIL Low-level input voltage –0.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 PIN CONFIGURATION DW PACKAGE SO-16 (TOP VIEW) R1IN 1 GND 2 16 VS R2IN 3 14 BUSY R3IN 4 13 CS 15 PWRD BUF 5 12 CONV CAP 6 11 EXT/INT REF 7 10 DATA GND 8 9 DATACLK Pin Assignments PIN DIGITAL I/O NAME NO. R1IN 1 Analog input. See Table 1 and Table 3. R2IN 3 Analog input.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com TYPICAL CHARACTERISTICS POWER-SUPPLY CURRENT vs FREE-AIR TEMPERATURE INTERNAL REFERENCE VOLTAGE vs FREE-AIR TEMPERATURE 5 4.5 4 -40 -25 -10 5 20 35 50 65 80 95 110 125 TA - Free-Air Temperature - ºC 2.510 2.505 2.500 2.495 2.490 2.485 5.5 5 4.5 4 10 2.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 TYPICAL CHARACTERISTICS (continued) UNIPOLAR POSITIVE FULL-SCALE ERROR vs FREE-AIR TEMPERATURE 1 0 -1 2 10 V Unipolar Range, Drift = 2.8 ppm/°C 4 V Unipolar Range, Drift = 0.1 ppm/°C 1 0 -1 -2 -45 -30 -15 0 15 30 45 60 75 90 105 120 TA - Free-Air Temperature - °C 0.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 TYPICAL CHARACTERISTICS (continued) OUTPUT REJECTION vs POWER-SUPPLY RIPPLE FREQUENCY CONVERSION TIME vs FREE-AIR TEMPERATURE -20 -25 Silicon tested under 10 V Bipolar range 17.7 Output Rejection - dB tCONVERT - Conversion Time - μs 17.8 17.6 17.5 17.4 -30 -35 -40 -45 -50 -55 17.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com TYPICAL CHARACTERISTICS (continued) FFT 0 -10 8192 Point FFT; fi = 20 kHz, 0 dB -20 Amplitude - dB -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 0 5 10 f - Frequency - kHz 15 20 Figure 32.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 BASIC OPERATION INTERNAL DATACLK Figure 34 shows a basic circuit to operate the ADS8513 with a ±10V input range using an internal DATACLK. To begin a conversion and serial transmission of the results from the previous conversion, a falling edge must be provided to the CONV input.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com STARTING A CONVERSION If a conversion is not currently in progress, a falling edge on the CONV input places the sample-and-hold into the hold mode and begins a conversion, as shown in Figure 36 according to the timing shown in Table 2. During the conversion, the CONV input is ignored.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 Even though the CONV input is ignored while a conversion is in progress, this input should be held static during the conversion period.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com READING DATA The ADS8513 digital output is in Binary Two’s Complement (BTC) format. Table 3 shows the relationship between the digital output word and the analog input voltage under ideal conditions. Table 3.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 CONV t25 t6 – t25 BUSY NOTE: Update of the internal shift register occurs in the shaded region. If EXT/INT is HIGH, then DATACLK must be LOW or CS must be HIGH during this time. Figure 38.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com Before reading the next three paragraphs, consult the Sensitivity to External Digital Signals section of this data sheet. This section explains many of the concerns regarding how and when to apply the external DATACLK signal.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 External DATACLK Active After the Conversion and During the Next Conversion Figure 42 shows a method that combines the two previous approaches. This method works very well for microcontrollers that do serial transfers eight bits at a time and for slower microcontrollers.
PAGE 18
ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com ANALOG INPUT The ADS8513 offers a number of input ranges. This set of options is accomplished by connecting the three input resistors to either the analog input (VIN), to ground (GND), or to the 2.5V reference buffer output (BUF).
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 The input impedance results from the various connections and the internal resistor values (refer to the block diagram on the front page of this data sheet). The internal resistor values are typical and can change by ±30% as a result of process variations.
PAGE 20
ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com DRIVING THE ADS8513 ANALOG INPUT In general, any reasonably fast, high-quality operational or instrumentation amplifier can be used to drive the ADS8513 input. When the converter enters the acquisition mode, there is some charge injection from the converter input to the amplifier output.
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ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 REFERENCE The ADS8513 can be operated with its internal 2.5V reference or an external reference. By applying an external reference voltage to the REF pin, the internal reference voltage is overdriven. The voltage at the REF input is internally buffered by a unity gain buffer.
PAGE 22
ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com POWER DOWN The ADS8513 has a power-down mode that is activated by taking CONV low and then PWRD high. This mode powers down all of the analog circuitry including the reference, reducing power dissipation to under 50µW. To exit the power-down mode, CONV is taken high and then PWRD is taken low.
PAGE 23
ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 LAYOUT POWER FOR TSSOP-20 PACKAGE For optimum performance, tie the analog and digital power pins to the same +5V power supply and tie the analog and digital grounds together. As noted in the Electrical Characteristics table, the ADS8513 uses 90% of its power for the analog circuitry.
PAGE 24
ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com If the result so far is getting very close to the actual input voltage, then the comparison involves two voltages that are very close together. The ADS8513 has been designed so that the internal noise sources are at a minimum just before the comparator result is latched.
PAGE 25
ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 APPLICATION INFORMATION TRANSITION NOISE Apply a dc input to the ADS8513 and initiate 1000 conversions. The digital output of the converter varies in output codes because the internal noise of the ADS8513. This condition is true for all 16-bit SAR converters.
PAGE 26
ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 2009 ...................................................................................................................................................... www.ti.com Convert Pulse QSPI ADS8513 CONV PCS0/SS MOSI SCK BUSY SDATA DATACLK CS EXT/INT CPOL = 0 (Inactive State is LOW) CPHA = 1 (Data Valid on Falling Edge) QSPI Port is in Slave Mode The ADC is the SPI master. Figure 50.
PAGE 27
ADS8513 www.ti.com ...................................................................................................................................................... SLAS486C – JUNE 2007 – REVISED JANUARY 2009 For the fastest conversion rate, the baud rate should be set to 2 (4.19MHz SCK), DT set to 10, the first serial transfer set to 8 bits, the second set to 16 bits, and DSCK disabled (in the command control byte). This allows for a 23kSPS maximum conversion rate.
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ADS8513 SLAS486C – JUNE 2007 – REVISED JANUARY 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 (August 2008) to Revision C ................................................................................................
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PACKAGE OPTION ADDENDUM www.ti.
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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 ADS8513IBDWR SOIC DW 16 2000 330.0 16.4 10.75 10.7 2.7 12.0 16.0 Q1 ADS8513IDWR SOIC DW 16 2000 330.0 16.4 10.75 10.7 2.7 12.0 16.
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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) ADS8513IBDWR SOIC DW 16 2000 367.0 367.0 38.0 ADS8513IDWR SOIC DW 16 2000 367.0 367.0 38.
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