LM12{L}438.PDF

July 1995

LM12434/LM12 À L Ó 438 12-Bit a Sign Data Acquisition

System with Serial I/O and Self-Calibration

General Description

The LM12434 and LM12 À L Ó 438 are highly integrated Data

Acquisition Systems. Operating on 3V to 5V, they combine a

fully-differential self-calibrating (correcting linearity and zero

errors) 13-bit (12-bit a sign) analog-to-digital converter

(ADC) and sample-and-hold (S/H) with extensive analog

and digital functionality. Up to 32 consecutive conversions,

using two's complement format, can be stored in an internal

32-word (16-bit wide) FIFO data buffer. An internal 8-word

instruction RAM can store the conversion sequence for up

to eight acquisitions through the LM12 À L Ó 438's eight-input

multiplexer. The LM12434 has a four-channel multiplexer, a

differential multiplexer output, and a differential S/H input.

The LM12434 and LM12 À L Ó 438 can also operate with 8-bit

a sign resolution and in a supervisory ``watchdog'' mode

that compares an input signal against two programmable

limits.

Acquisition times and conversion rates are programmable

through the use of internal clock-driven timers. The differen-

tial reference voltage inputs can be externally driven for ab-

solute or ratiometric operation.

All registers, RAM, and FIFO are directly accessible through

the high speed and flexible serial I/O interface bus. The

serial interface bus is user selectable to interface with the

following protocols with zero glue logic: MICROWIRE/

PLUS TM , Motorola's SPI/QSPI, Hitachi's SCI, 8051 Family's

Serial Port (Mode 0), I 2 C and the TMS320 Family's Serial

Port.

An evaluation kit for demonstrating the LM12434 and

LM12 À L Ó 438 is available.

TRI-STATE É is a registered trademark of National Semiconductor Corporation.

MICROWIRE/PLUS TM is a trademark of National Semiconductor Corporation.

Windows É is a registered trademark of Microsoft Corporation.

Key Specifications

f CLK e 8 MHz À L, f CLK e 6 MHz Ó

Y Resolution

12-bit a sign or 8-bit a sign

Y 13-bit conversion time

5.5 m s À 7.3 m s Ó (max)

Y 9-bit conversion time

2.6 m s À 3.5 m s Ó (max)

Y 13-bit Through-put rate

140k samples/s À 105k sample/s Ó (min)

Y Comparison time (``watchdog'' mode)

1.4 m s À 1.8 m s Ó (max)

Y Serial Clock

10 MHz À 6 MHz Ó (max)

Y Integral Linearity Error

g 1 LSB (max)

Y Power dissipation

45 mW À 20 mW Ó (max)

GND to V A a

Y Stand-by mode

power dissipation

25 m W À 16.5 m W Ó (typ)

Y Supply voltage LM12L438

3.3V g 10%

LM12434/8

5V g 10%

Features

Y Three operating modes: 12-bit a sign, 8-bit a sign,

and ``watchdog'' comparison mode

Y Single-ended or differential inputs

Y Built-in Sample-and-Hold

Y Instruction RAM and event sequencer

Y 8-channel (LM12 À L Ó 438) or 4-channel (LM12434)

multiplexer

Y 32-word conversion FIFO

Y Programmable acquisition times and conversion rates

Y Self-calibration and diagnostic mode

Y Power down output for system power management

Y Read while convert capability for maximum through-put

rate

Applications

Y Data Logging

Y Portable Instrumentation

Y Process Control

Y Energy Management

Y Robotics

Connection Diagrams

28-Pin PLCC Package

28-Pin Wide Body SO Package

TL/H/11879±1

TL/H/11879±2

Order Number LM12434CIWM, LM12438CIWM, or

LM12L438CIWM

See NS Package Number M28B

*Pin names in ( ) apply to the LM12434

Order Number LM12434CIV, LM12438CIV, or

LM12L438CIV

See NS Package Number V28A

C 1995 National Semiconductor Corporation

TL/H/11879

RRD-B30M85/Printed in U. S. A.

Y V IN range

Table of Contents

1.0 FUNCTIONAL DIAGRAMS ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ3

7.0 DIGITAL INTERFACE ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ43

7.1 Standard Interface Mode ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ43

7.1.1 Examples of Interfacing to the HPC 46XXX's

MICROWIRE/PLUS TM and 68HC11's SPI ÀÀÀ50

7.2 8051 Interface ModeÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ59

7.2.1 Example of Interfacing to the 8051ÀÀÀÀÀÀÀÀÀÀ62

7.3 TMS320 Interface ModeÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ66

7.3.1 Example of Interfacing to the TMS320C3x ÀÀÀ69

7.4 I 2 C Bus Interface ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ74

7.4.1 Example of Interfacing to an I 2 C ControllerÀÀÀ76

2.0 ELECTRICAL SPECIFICATIONS ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.1 Ratings ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.1.1 Absolute Maximum Ratings ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.1.2 Operating Ratings ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.2 Performance Characteristics ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.2.1 Converter Static Characteristics ÀÀÀÀÀÀÀÀÀÀÀÀÀ5

2.2.2 Converter Dynamic Characteristics ÀÀÀÀÀÀÀÀÀÀ6

2.2.3 DC CharacteristicsÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ8

2.2.4 Digital DC CharacteristicsÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ9

2.3 Digital Switching CharacteristicsÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ10

2.3.1 Standard Interface Mode ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ10

2.3.2 8051 Interface ModeÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ11

2.3.3 TMS320 Interface ModeÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ12

2.3.4 I 2 C Bus Interface ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ13

2.4 Notes on Specifications ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ14

8.0 ANALOG CONSIDERATIONS ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.1 Reference Voltage ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.2 Input Range ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.3 Input Current ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.4 Input Source Resistance ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.5 Input Bypass Capacitance ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.6 Input Noise ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.7 Power Supply Consideration ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ77

8.8 PC Board Layout and Grounding ConsiderationÀÀÀÀ78

3.0 ELECTRICAL CHARACTERISTICS ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ15

4.0 TYPICAL PERFORMANCE CHARACTERISTICS ÀÀÀ19

5.0 PIN DESCRIPTIONS ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ23

6.0 OPERATIONAL INFORMATION ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ27

6.1 Functional Description ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ27

6.2 Internal User-Accessible Registers ÀÀÀÀÀÀÀÀÀÀÀÀÀÀ31

6.2.1 Instruction RAMÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ31

6.2.2 Configuration Register ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ38

6.2.3 InterruptsÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ38

6.2.4 Interrupt Enable Register ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ39

6.2.5 Interrupt Status Register ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ39

6.2.6 Limit Status Register ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ40

6.2.7 Timer ÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ40

6.2.8 FIFOÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ40

6.3 Instruction SequencerÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀÀ41

1.0 Functional Diagrams

LM12434

TL/H/11879±3

INTERFACE MODESEL1 MODESEL2 P1 P2 P3 P4 P5

Standard

R/F CS DI DO SCLK

8051

1* CS RXD TXD

I 2 C

SAD0 SAD1 SAD2 SDA SCL

TMS320

FSR FSX DX DR SCLK

*Internal pull-up

Ordering Information (LM12434)

Part Number

Package Type

NSC Package Number

Temperature Range

LM12434CIV

28-Pin PLCC

V28A

b 40 § Cto a 85 § C

LM12434CIWM

28-Pin Wide Body SO

M28B

b 40 § Cto a 85 § C

1.0 Functional Diagrams (Continued)

LM12 À L Ó 438

TL/H/11879±4

INTERFACE MODESEL1 MODESEL2 P1 P2 P3 P4 P5

Standard

R/F CS DI DO SCLK

8051

1* CS RXD TXD

I 2 C

SAD0 SAD1 SAD2 SDA SCL

TMS320

FSR FSX DX DR SCLK

*Internal pull-up

Ordering Information (LM12 À L Ó 438)

Part Number

Package Type

NSC Package Number

Temperature Range

LM12438CIV

28-Pin PLCC

V28A

b 40 § Cto a 85 § C

LM12L438CIV

LM12438CIWM

28-Pin Wide Body SO

M28B

b 40 § Cto a 85 § C

LM12L438CIWM

LM12438 Eval

Evaluation Board and Windows É based software

2.0 Electrical Specifications

2.1 RATINGS

2.1.1 Absolute Maximum Ratings (Notes1&2)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales

Office/Distributors for availability and specifications.

Supply Voltage (V A a and V D a )

6.0V

2.1.2 Operating Ratings (Notes1&2)

Temperature Range (T min s T A s T max )

LM12434CIV/LM12 À L Ó 438CIV b 40 § C s T A s 85 § C

LM12434CIWM, LM12 À L Ó 438CIWM b 40 § C s T A s 85 § C

Supply Voltage

V A a ,V D a

3.0V to 5.5V

l V A a b V D a l

s 100 mV

Voltage at Input and Output Pins

except IN0±IN3 (LM12434) b 0.3V to V a a 0.3V

and IN0±IN7 (LM12 À L Ó 438)

Voltage at Analog Inputs IN0±IN3 (LM12434)

and IN0±IN7 (LM12 À L Ó 438) GND b 5V to V a a 5V

l V A a b V D a l

l AGDND b DGND l

s 100 mV

Analog Inputs Range

GND s V IN a s V A a

V REF a Input Voltage

1V s V REF a s V A a

V REF b Input Voltage

0V s V REF b s V REF a b 1V

300 mV

V REF a b V REF b

1V s V REF s V A a

l AGND b DGND l

300 mV

V REF Common Mode

Range (Note 16)

Input Current at Any Pin (Note 3)

g 5mA

0.1 V A a s V REFCM s 0.6 V A a

Package Input Current (Note 3)

g 20 mA

Power Dissipation (T A e 25 § C) (Note 4)

V Package

WM Package

Storage Temperature b 65 § Cto a 150 § C

Soldering Information, Lead Temperature (Note 19)

V Package, Vapor Phase (60 seconds)

Infrared (15 seconds)

WM Package, Vapor Phase (60 seconds)

Infrared (15 seconds)

ESD Susceptibility (Note 5)

1.5 kV

2.2 PERFORMANCE CHARACTERISTICS All specifications apply to the LM12434, LM12438, and LM12L438 unless otherwise

noted. Specifications in braces ÀÓ apply only to the LM12L438.

2.2.1 Converter Static Characteristics The following specifications apply to the LM12434 and LM12 À L Ó 438 for V A a e

V D a e 5V À 3.3V Ó , AGND e DGND e 0V, V REF a e 4.096V À 2.5V Ó ,V REF b e 0V, 12-bit a sign conversion mode, f CLK e

8.0 MHz À 6 MHz Ó ,R S e 25 X , source impedance for V REF a and V REF b s 25 X , fully-differential input with fixed 2.048V

À 1.25V Ó common-mode voltage, and minimum acquisition time unless otherwise specified. Boldface limits apply for T A e

T J e T MIN to T MAX ; all other limits T A e T J e 25 § C. (Notes 6, 7, 8 and 9)

Symbol

Parameter

Conditions

Typical

Limits

Units

(Note 10)

(Note 11)

(Limit)

ILE

Positive and Negative Integral

After Auto-Cal (Notes 12, 17)

g 0.35

g 1 LSB (max)

Linearity Error

TUE

Total Unadjusted Error

After Auto-Cal (Note 12)

g 1

LSB

Resolution with No Missing Codes

After Auto-Cal (Note 12)

Bits

DNL

Differential Non-Linearity

After Auto-Cal

g 0.2

g 1 LSB (max)

Zero Error

After Auto-Cal (Notes 13, 17)

g 0.2

g 1 LSB (max)

Positive Full-Scale Error

After Auto-Cal (Notes 12, 17) g 0.2

g 2 LSB (max)

Negative Full-Scale Error

After Auto-Cal (Notes 12, 17) g 0.2

g 2 LSB (max)

DC Common Mode Error

(Note 14)

g 2

g 3.5 LSB (max)

À g 4.0 Ó

ILE

8-Bit a Sign and ``Watchdog''

(Note 12)

Mode Positive and Negative

g 0.15 g 1/2 LSB (max)

Integral Linearity Error

TUE

8-Bit a Sign and ``Watchdog'' Mode After Auto-Zero

g 1/2 g 1/2 LSB (max)

Total Unadjusted Error

8-Bit a Sign and ``Watchdog'' Mode

Bits (max)

Resolution with No Missing Codes

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika: