ADC0858BIV National Semiconductor, ADC0858BIV Datasheet

IC DATA ACQUISITION/MON 20-PLCC

ADC0858BIV

Manufacturer Part Number
ADC0858BIV
Description
IC DATA ACQUISITION/MON 20-PLCC
Manufacturer
National Semiconductor
Type
Data Acquisition System (DAS)r
Datasheet

Specifications of ADC0858BIV

Resolution (bits)
8 b
Data Interface
NSC MICROWIRE™, Serial
Voltage Supply Source
Single Supply
Voltage - Supply
5V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
*
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Sampling Rate (per Second)
-
Other names
*ADC0858BIV
C 1995 National Semiconductor Corporation
ADC0851 and ADC0858 8-Bit Analog Data
Acquisition and Monitoring Systems
General Description
The ADC0851 and ADC0858 are 2 and 8 input analog data
acquisition systems They can function as conventional mul-
tiple input A D converters automatic scanning A D convert-
ers or programmable analog ‘‘watchdog’’ systems In
‘‘watchdog’’ mode they monitor analog inputs and deter-
mine whether these inputs are inside or outside user pro-
grammed window limits This monitoring process takes
place independent of the host processor When any input
falls outside of its programmed window limits an interrupt is
automatically generated which flags the processor the chip
can then be interrogated as to exactly which channels
crossed which limits
The advantage of this approach is that its frees the proces-
sor from having to frequently monitor analog variables It
can consequently save having to insert many A D subrou-
tine calls throughout real time application code In control
systems where many variables are continually being moni-
tored this can significantly free up the processor especially
if the variables are DC or slow varying signals
The Auto A D conversion feature allows the device to scan
through selected input channels performing an A D conver-
sion on each channel without the need to select a new
channel after each conversion
Applications
Y
Y
Y
Simplified Block Diagram
TRI-STATE is a registered trademark of National Semiconductor Corporation
MICROWIRE
Instrumentation monitoring and process control
Digitizing automotive sensor signals
Embedded diagnostics
TM
is a trademark of National Semiconductor Corporation
TL H 11021
FIGURE 1
Key Specifications
Y
Y
Y
Y
Y
Features
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Y
Resolution
Total error
Low power
Conversion time
Limit comparison time
Watchdog operation signals processor when any
channel is outside user programmed window limits
Frees microprocessor from continually monitoring
analog signals and simplifies applications software
2 (ADC0851) or 8 (ADC0858) analog input channels
Single ended or differential input pairs
COM input for DC offsetting of input voltage
4 (ADC0851) and 16 (ADC0858) 8-bit programmable
limits
NSC MICROWIRE
Power fail detection
Auto A D conversion feature
Single 5V supply
Window limits are user programmable via serial inter-
face
TM
interface
g
RRD-B30M75 Printed in U S A
LSB or
18 s Channel
TL H 11021– 22
January 1995
2 s Limit
g
50 mW
1 LSB
8 Bits

Related parts for ADC0858BIV

ADC0858BIV Summary of contents

Page 1

... Applications Instrumentation monitoring and process control Y Digitizing automotive sensor signals Y Embedded diagnostics Y Simplified Block Diagram TRI-STATE is a registered trademark of National Semiconductor Corporation MICROWIRE trademark of National Semiconductor Corporation C 1995 National Semiconductor Corporation TL H 11021 Key Specifications Resolution Y Total error ...

Page 2

... ADC0851BIN N16E 16-Pin ADC0851CIN Plastic DIP ADC0858BIN N20A 20-Pin ADC0858CIN Plastic DIP ADC0851BIV V20A 20-Lead ADC0851CIV PLCC ADC0858BIV V20A 20-Lead ADC0858CIV PLCC 8-Channel MUX Dual-In-Line Package TL H 11021–1 ADC0858 PLCC Package TL H 11021–3 Military ( 125 ADC0851CMJ 883 ADC0858CMJ 883 ...

Page 3

... J Parameter CONVERTER AND MULTIPLEXER CHARACTERISTICS Total Unadjusted Error (Note 7) ADC0851 8 BIN ADC0851 8 BIV ADC0851 8 CIN ADC0851 8 CMJ ADC0851 8 CIV Comparator Offset ADC0851 8 BIN ADC0858BIV ADC0851 8 CIN ADC0851 8 CMJ ADC0858CIV V Input Resistance REF Common Mode Input Voltage (Note 8) DC Common Mode Error ...

Page 4

DC Electrical Characteristics The following specifications apply for 170 pF) unless otherwise specified Boldface limits apply for T e ext Parameter DIGITAL CHARACTERISTICS Logic ...

Page 5

AC Electrical Characteristics The following specifications apply for unless otherwise specified Boldface limits apply for T Symbol Parameter t t Rising Edge Data Output Hi-Z f Oscillator Clock Freq ...

Page 6

Typical Performance Characteristics Offset Error vs Reference Voltage OSC Frequency vs Temperature Linearity Error vs Total Unadjusted Error Reference Voltage vs Temperature OSC Frequency vs R and C ext ext 11021 – 5 ...

Page 7

Test Circuits and Waveforms Timing Diagrams Data Input Timing 11021 – 11021 – 7 Data Output Timing TL H 11021 – ...

Page 8

Timing Diagrams (Continued) Timing Diagrams for ADC0851 and ADC0858 Read Power Flag after Power Up ADC0851 ADC0858 Watchdog Timing A D Conversion Timing 11021 – 11021 – 11021 – 14 ...

Page 9

Timing Diagrams for ADC0851 and ADC0858 (Continued) 9 ...

Page 10

Timing Diagrams for ADC0851 and ADC0858 (Continued) 10 ...

Page 11

Timing Diagrams for ADC0851 and ADC0858 (Continued) 11 ...

Page 12

ADC0851 Programming Chart Receive (DI) Function Mode Watchdog 1000 C11 C0 Write 1 Limit 1001 Conversion 1010 I3 I0 Read 1 Limit 1011 A3 A0 Test 1100 Write all Limits 1101 4 Bytes L0 ...

Page 13

Pin Descriptions V Positive power supply pin Bypass to analog CC ground with ceramic capacitor in parallel with tantalum capacitor OSC Input Output pin used to generate internal timing for A D conversion ...

Page 14

General Overview The ADC0851 versatile microprocessor-compatible data acquisition system with an on-board watchdog capabili- ty The device is capable of synchronous serial interface with most microprocessors and includes a multiplexer a RAM and a successive approximation register ...

Page 15

Modes of Operation (Continued READ ALL LIMITS FROM RAM This mode of operation allows the device to serially output 8-bit limit data from each memory location in succession starting with CH0-lower limit (see Section 2 4 ...

Page 16

Programming Information (Continued) limits while the odd addresses correspond to the upper lim- its The ADC0851 and ADC0858 both use four bits (A3–A0) to address the limit RAM but the ADC0851 only decodes the two LSBs while ignoring ...

Page 17

Functional Description (Continued) croprocessor can then initiate conversion on any channel(s) The ADC0851 includes two additional output pins COMPL and COMPH During watchdog operation if either of the inputs exceeds its respective window bounds then not only ...

Page 18

Memory Access Modes The ADC0851 8 has an internal RAM with sixteen memory locations (one location for the upper limit and one for the lower limit for each of the 8 input channels) Each memory location is 8 ...

Page 19

Memory Access Modes Note that the memory address is clocked in with the MSB (bit A3) first whereas the limit data is clocked in with the LSB (bit L0) first Figure 3 shows the timing diagram for writing ...

Page 20

Memory Access Modes The address bits access specific memory locations as per Table II(a) and (b) for the ADC0851 and ADC0858 respec- tively The address data is clocked in with the MSB (bit A3) first The timing diagram ...

Page 21

Watchdog Mode This is the primary real time operating mode During watch- dog operation the upper and lower limits stored in the RAM are applied sequentially to the DAC’s digital inputs The DAC’s analog output is applied to ...

Page 22

Watchdog Mode (Continued) 22 ...

Page 23

Watchdog Mode (Continued) The device will read the new input word and configure to a different mode high for less than eight oscillator clock periods for the ADC0851 and less than thirty-two os- cillator clock ...

Page 24

Watchdog Mode (Continued) their respective window limits A logical ‘‘1’’ will be placed in the appropriate location of the status register for each limit that is crossed as the device cycles through the remaining channels Note that the ...

Page 25

Watchdog Mode (Continued Conversion Modes The ADC0851 8 can be used in two A D conversion modes In ‘‘One A D conversion’’ mode the device oper- ates as a multiplexed A D converter and ...

Page 26

A D Conversion Modes TABLE V(b) Channel Information for One A D Conversion (ADC0858) Channel Information Channels Enabled CH0 CH0–CH1 CH1 0 ...

Page 27

A D Conversion Modes The 12-bit channel address following the mode address as- signs the MUX configuration as per Table III(a) and (b) for ADC0851 and ADC0858 respectively ADC0851 only decodes the three LSBs (C0 C1 and C2) ...

Page 28

A D Conversion Modes (Continued) 28 ...

Page 29

A D Conversion Modes The first eight bits of the output word represents the digital equivalent of the analog input voltage Status bits I3 through I0 provide the channel configuration information as per Ta- ble V(a) and (b) ...

Page 30

The Analog Inputs (Continued) resistance Another source of error is the sampling nature of the A D converter Short spikes of current enter the ‘‘ input and exit the ‘‘ ’’ input at the rising and falling tran- ...

Page 31

Typical Applications (Continued) FIGURE 13 Over Voltage Protection of the Analog Inputs Single Ended TL H 11021–57 FIGURE 14 Analog Input Multiplexer Options for ADC0851 Single Ended Pseudo-Differential TL H 11021– 60 FIGURE 15 Analog Input Multiplexer Options for ADC0858 ...

Page 32

Typical Applications (Continued) FIGURE 16 Adaptive Instrumentation Control (Ratiometric Operation) with Over Range Flag FIGURE 18 Absolute Input with 2 5V Input Voltage Span FIGURE 17 Remote Temperature Sensor with Over Range Flag TL H 11021– 11021– ...

Page 33

33 ...

Page 34

Physical Dimensions inches (millimeters) 16-Pin Ceramic DIP Order Number ADC0851CMJ 883 NS Package Number J16A 20-Pin Ceramic DIP Order Number ADC0858CMJ 883 NS Package Number J20A 34 ...

Page 35

Physical Dimensions inches (millimeters) (Continued) Order Number ADC0851BIN or ADC0851CIN Order Number ADC0858BIN or ADC0858CIN 16-Pin Plastic DIP NS Package Number N16E 20-Pin Plastic DIP NS Package Number N20A 35 ...

Page 36

... National does not assume any responsibility for use of any circuitry described no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications 20-Lead PLCC ADC0858BIV or ADC0858CIV NS Package Number V20A 2 A critical component is any component of a life ...

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