Tektronix LA 501 User manual

Tektronix , Inc.
P.O. Box 500
Beaverton , Oregon
97077
070-2047-00
TEKTRONIX
LA 501
LOGIC
ANALYZER
WITH
OPTIONS
OPERATORS
INSTRUCTION
MANUAL
Serial Number
First
Printing SEP 1975

WU
WARRANTY
All TEKTRONIX instruments are warranted against
defective
materials and
workmanship
for
one
year
.
Any
questions
with
respect to the
warranty should
be taken up with your TEKTRONIX Field Engineer or
representative
.
All requests for repairs and replacement parts
should be directed to the TEKTRONIX Field Office
or representative in your area . This will assure you
the
fastest possible
service .
Please
include
the
instrument Type Number or Part Number and Serial
Number with all requests for parts or service .
Specifications and price change privileges reserved .
Copyright 1975 by Tektronix , Inc. , Beaverton ,
Oregon . Printed in the United States of America . All
rights reserved . Contents of this publication may not
be reproduced in any form without permission of
Tektronix
,
Inc.
U.S.A. and foreign TEKTRONIX products covered
by U.S. and foreign patents and / or patents pending .
TEKTRONIX is a registered trademark of Tektronix ,
Inc.
$

LIST
OF
ILLUSTRATIONS
LIST OF
TABLES
SECTION
1
OPERATING
INSTRUCTIONS
TM 500 -
SERIES
INSTRUMENTS
SAFETY
INFORMATION
Component Replacement
Soldering
TABLE OF CONTENTS
PAGE
¡ ¡
Semiconductor
Replacement
FRONT -
PANEL
CONTROLS
,
CONNECTORS , AND INDICATORS
INTERNAL CONNECTORS AND SWITCHES
1-1
Data Input Connector
1-1
Data Output Connector
1-1
1-4
1-5
1-5
1-5
1-6
1-6
1-6
1-7
1-8
1-9
1-10
1-10
1-10
External Clock Threshold Switch ( S848 )
Blanking Polarity Switch ( S720 )
Display Clock Switch ( S835 )
INSTALLATION
FUNCTIONAL CHECK
1-1
1-1
1-1
1-1
1-1
1-1
Test
Equipment
Required
Preliminary Set Up
Raster
Display
Display
Functions
Trigger
Functions
DETAILED
OPERATING
INFORMATION
Signal
Connection
Display
Monitor
SECTION 1 ( CONT . )
Sample
Interval
External
Clock
Input
Input
Threshold
Controls
Trigger
Controls
Format
Switches
Record
Controls
Monitor Output Signals and Controls
Data
Input
Signals
Data Output Connector
P300 Signal Selector
Internal
Switches
LA 501 GLOSSARY
APPLICATIONS
MICROPROCESSORS
STORAGE BUFFERS
SECTION 2 SPECIFICATION
STANDARD ACCESSORIES
RECOMMENDED ACCESSORIES
SECTION 3 INSTRUMENT OPTIONS
SECTION 4 BLOCK DIAGRAM
ACCESSORIES
LA
501
Operators
CHANGE
INFORMATION
PAGE
1-10
1-10
1-12
1-13
1-13
1-13
1-13
1-14
1-14
1-16
1-18
1-18
1-20
1-20
1-21
2-7
2-8

LA
501
Operators
FIGURE
NO .
Frontis
piece
1-1
=
:
1-2
1-3
1-4
1-5
1-6
1-7
1-8
LIST OF ILLUSTRATIONS
LA
501
Logic
Analyzer .
Front - panel controls , connectors , and
indicators .
Location of internal connectors and
switches .
LA 501
installation
and
removal
.
Equipment set up
for Functional
Check .
LA 501 and
monitor
X , Y ,
and Z signal
connections for Functional Check .
10X probe compensation set up and
procedure .
Location
of
EXT
CLOCK
polarity
selector
.
Pin assignments for the DATA INPUT
connector
,
J100 .
PAGE
iv
1-2
1-4
1-5
1-7
1-8
1-11
1-12
1-15
FIGURE
NO
.
1-9
1-10
1-11
1-12
1-13
1-14
2-1
Pin
assignments
for
the
DATA OUTPUT
connector ,
J120 .
Location of Signal Selector P300 , and
P300
pin
assignments .
P300 jumper placement procedure .
Internal Switch locations , and switch
selection
positions .
Typical set up for troubleshooting a
microprocessor
system with
the LA 501
Logic
Analyzer
.
Typical set up
and
display for trouble
shooting
a
storage
buffer
with
the
LA 501
Logic
Analyzer
.
LA 501
dimensional
drawing .
PAGE
1-16
1-17
1-18
1-19
1-20
1-21
2-6
Ⓡ
●

O
TABLE
NO .
1-1
2-1
6
Format
Output Levels at P300
Electrical
LIST OF TABLES
PAGE
1-17
2-1
TABLE
NO .
2-2
2-3
Environmental
Physical
LA
501
Operators
PAGE
2-6
2-6
iii

LA
501
Operators
iv
SAMPLE
INTERVAL
-IMS
20pF .
(
10X PROBE
ONLY
EXT
CLOCK
MONITOR
CH
TEKTRONIX
OZ
05 t
100K
230p
EXT
TRIG
2018
THRESHOLD
THRESHOLD
+
1.4V
EXT
INPUT
VAR
M
20pF
10X
PROBE
ONLY
CH 1
CH 2
ECL
MONITOR
FORMAT
CH
0-3
*
1024
CH
0.7
*
512
20ns
MAX
CH
0-15
*
256
50ms
MAX
TRIGGER
DATA
OUTPUT
TRIG D
CH
3
POST
CENTER
PRE
SLOPE
+
SOURCE
CH
O
EXT
INPUTS
PROBE
BNC
RECORD
DISPLAY
TIME C -
MANUAL
'
BLANK
OUT
LA
501
LOGIC
ANALYZER
CHANNEL /
POSITION
SELECT
POSITION
OFF
16
15
MAG
- C -
POS
MAG
- C
POS
X1
(
NORM
)
VERT
OUT
X1
(
NORM
)
HORIZ
OUT
DATA
INPUT
LA
501 Features
The
LA
501
Logic
Analyzer is
designed
for
rapid
troubleshooting of
digital
equipment
. The
simultaneous
multi -
channel .
raster can
be
displayed on
almost
any low
- frequency
X -
Y monitor
or
oscilloscope .
The
4096 - bit
memory can
be
formatted
into 4
channels
of
1024
data bits , 8
channels
of 512
data bits
, or 16
channels
of
256 data
bits , for
a wide
range of bit serial
, byte
serial , or word
serial
data .
The
flexible
external
( synchronous
) or
internal (
asynchronous )
sample rate
clock
capability will
accomodate
nearly
all
of the logic family speeds in use .
Three
trigger
delay modes ( PRE
, CENTER
, and
POST )
allows selection
of the best
mode for the
application .
Negative
trigger
delay ( PRE
)
allows analysis
of the
sequence
of events
that
precede a
fault trigger
.
Digital data
outputs
provide a
serial or
parallel
format to " loop
back "
stored
data
to a
computer for
quick
error
checks .
This
feature
allows analysis or
logging of data while
viewing it , or it can
be used
without a
display
device .
Horizontal and
vertical
magnification ,
with
positioning , provide
high
resolution . A
unique vertical
positioning
system .
allows the
selection and
positioning
of any one
trace for
timing
comparisons with
other traces
in the raster
.
The
LA 501
can be
powered by any
TM - 500 -
series
power module
which has three
- unit , or
greater ,
capability .
1967-1

OPERATING INSTRUCTIONS
TM 500 - SERIES INSTRUMENTS
The LA 501 Logic Analyzer is a member of Tektronix '
growing TM 500 line of Test and Measurement Instruments .
This product line consists of both general- and special - purpose
instruments such as digital
multimeters
,
counter
-
timers ,
variable dc
power
supplies ,
pulse
generators ,
function
gener
ators ,
calibration
sources
,
oscilloscopes ,
signal
processors ,
and others . Each instrument is a plug - in module . Power
module
mainframes with 1 , 3 ,
4 , 5 , and 6
compartments
are
available . The power module provides power and an overall
housing for the plug - in modules , and permits internal signal
interconnections
between
plug - in
instruments
to
reduce
clutter or to allow two or more instruments to perform a
function
which
neither could
perform alone .
Each user can
thus select from
a broad choice
of
instrumentation to
assemble a multi - function test set to fit his needs . This test
set is
compact and
portable
; yet
it can be quickly
recon
figured by exchanging plug - in instruments when test needs
change . TM 500 systems can be configured for benchtop ,
rackmount , roll - about , and portable applications . For more
information on the
TM 500
line ,
please
contact your Tek
tronix
Field Office or
representative
.
SAFETY INFORMATION
The following warnings must be observed during maintenance
and adjustment of the LA 501 .
Component Replacement
To avoid
electrical shock ,
disconnect
the LA 501
from the
power
source before
replacing
components
.
Soldering
To avoid electrical shock , disconnect the LA 501 from the
power source before soldering .
Semiconductor
Replacement
Semiconductors that have
heat
radiators
use
silicone
grease
to increase heat
transfer . When
one of these
semiconductors
is replaced , the silicone grease must also be replaced . Handle
silicone
grease
with care .
Avoid getting
silicone grease in
eyes . Wash hands thoroughly after use .
FRONT -
PANEL
CONTROLS
,
CONNECTORS , AND INDICATORS
The major
controls
and
connectors for
operation of the
LA 501 are located on the front panel . Figure 1-1 shows
and
briefly
describes the front -
panel
controls
,
connectors ,
Section 1 - LA 501
and indicators . More information is given under Detailed
Operating Information in this section .
Several connectors and switches are located inside the
LA 501. These are described under Internal Connectors
and Switches in this section .
INTERNAL CONNECTORS AND SWITCHES
Figure 1-2 shows the location of the internal connectors and
switches . A brief description of these internal functions is
given here . More information is given under Detailed Oper
ating Information in this section .
A Data Input Connector
Multi - pin connector for use with the Data Acquisition Probe
to
provide
the
following
functions :
DATA INPUTS . Provides input for each of the 16 channels
( selected when the front - panel INPUTS switch is in the
PROBE
position
) .
CLOCK OUT . Provides signal output from the internal
clock .
INVALID MODE . Provides an input to indicate an external
source sample
interval
that
is too fast for
the
selected
memory
format ( selected by jumper - connector P300 ) .
B Data Output Connector
Multi - pin connector with the following functions :
PARALLEL
DATA
OUTPUT
.
Provides
outputs for each of
the 16 memory channels .
SERIAL DATA OUTPUT . Provides an output for serial
data
from
the
memory .
FLAG
OUTPUT .
Provides an
output that
indicates the start
of each channel of data .
FORMAT
OUTPUT
.
Provides
an
output
that
indicates
memory format ( selected by jumper - connector P300 ) .
1-1

Operating Instructions - LA 501
1-2
1
2
16
15
14
13
12
INPUT
SAMPLE
INTERVAL
MS 20pF
10X
PROBE ONLY
EXT
CLOCK
2000
2001
MONITOR
CH
1
TEKTRONIX®
≈100K
230pf
10
EXT TRIG
THRESHOLD + 1.4V
2
THRESHOLD
M3 200F 10X PROBE ONLY
CH 1
CH 2
VAR
TTL
ECL
INPUT TRIGGER
MONITOR
FORMAT
CH 0-3
*
1024
CH0-7
*
512
20m
MAX
CH
0-15
*
258
500
MAX
CH 3
3
DATA
OUTPUT
TRIG'D
POST
CENTER
PRE
SLOPE
L
+
SOURCE
INPUTS
CH
EXT
L PROBE
L.
BNC
4
LA
501
LOGIC
ANALYZER
RECORD
DISPLAY TIME - C -
MANUAL
10s
BLANK OUT
CHANNEL /
POSITION
SELECT
C
POSITION
MAG -
POS
X1
( NORM )
X5
Y
VERT OUT
MAG - C - POS
XI
(
NORM )
Fig . 1-1 . Front -
panel controls ,
connectors
, and
indicators
.
DATA
INPUT
X10
X
HORIZ OUT
5
6
7
8
9
SAMPLE INTERVAL Switch - Selects data input sample interval . The EXT position selects input from the EXT CLOCK
connector . The knob skirt lamp blinks when the sample interval is too fast when in 8 or 16 channel record format .
10
11
THRESHOLD Control : Provides a variable threshold voltage level for data input channels ( selected by VAR switch ) .
MONITOR Pin Jack : Provides an output to monitor the dc threshold voltage level of the data input channels .
VAR Switch : Selects the variable THRESHOLD control .
TTL Switch : Selects a preset data input threshold voltage level for TTL logic .
ECL Switch : Selects a preset data input threshold voltage level for negative voltage ECL logic .
(
8
)

6
3
TRIGGER
4
5
6
7
8
TRIG'D Indicator : Lights when record circuit has received a trigger signal .
POST Switch : Selects data to be stored after the trigger .
CENTER Switch : Selects data to be stored before and after the trigger .
PRE
Switch :
Selects data to be
stored
before
the
trigger
.
SLOPE Switch : Selects the positive or negative - going edge of the record trigger signal .
SOURCE Switch : Selects Channel or EXT TRIG connector for record trigger source .
RECORD
DISPLAY TIME Control : A variable control sets the time which memory stored data will be held for display before a
new record cycle
begins .
MANUAL Switch : A push button switch which resets the trigger circuit to start a new record cycle .
CHANNEL / POSITION
16
SELECT Switch : Selects any
channel
for
positioning
within
the raster .
POSITION Control : Vertically positions channel selected by SELECT switch .
Operating
Instructions
-
LA 501
INPUTS Switch - Selects data
input signals
from CH
through
CH 3
front - panel BNC
high
impedance
connectors or the
internal low impedance DATA INPUT connector .
9
Z
BLANK OUT
Connector -
BNC
connector for
output
of crt
retrace
blanking
pulses
.
10 X HORIZ OUT Connector - BNC connector for output of horizontal ( X - axis ) display signal .
11
Y VERT OUT
Connector
-
BNC
connector for output
of Y - axis
display
signal .
MAG / POS
Controls
-
Provides
variable
vertical
magnification
(
X1 to X5 ) and
vertical
positioning
of the
displayed
raster .
MAG / POS
Controls
-
Provides variable
horizontal
magnification ( X1 to X10 )
and
horizontal
positioning of the
displayed
raster .
12 ) CH
Through CH 3
Connectors - BNC
connectors for data inputs
with 10X probes
( selected by
INPUTS switch in the
BNC
position
) .
13
MONITOR
Probe -
Tip
Connector
-
Provides output to
monitor the EXT
CLOCK
connector
when
compensating
high
impe
dance
10X
probes
.
( 14 ) EXT
CLOCK Connector - BNC
connector
for
input of
external
sampling clock signal (
selected
by
SAMPLE INTERVAL
switch
in
the EXT
position
) .
15 ) EXT TRIG
Connector
- BNC
connector
for external
input to record
trigger circuit (
selected by SOURCE
switch in the EXT
position
) .
FORMAT
CH 0-3 X 1024 Switch : Selects channel through channel 3 for data recording with 1024 bits of memory per channel .
CH 0-7 X 512
Switch : Selects
channel
through channel 7
for data
recording with 512 bits
of
memory
per
channel .
Maximum
sample
interval
is 50
nanoseconds
.
CH 0-15 X 256
Switch : Selects
channel through
channel 15 for data
recording with 256 bits
of memory per
channel .
Maximum
sample interval is 20
nanoseconds .
Fig . 1-1 . Front - panel controls , connectors , and indicators . ( Continued )
1967-6
1-3

Operating
Instructions - LA 501
BLANKING
POLARITY
SWITCH
S720
D
EXT CLOCK
THRESHOLD
SWITCH S848
C
DISPLAY - STORE MODE OUTPUT . Provides an output to
indicate whether the memory is in a Display or Store Mode
( selected by jumper - connector P300 ) .
1-4
FRAME
OUTPUT
.
Provides
an
output
to
show a
complete
memory scan
when
reading the
memory
serially
(
selected
by
jumper -
connector
P300 ) .
DISPLAY - CLOCK OUTPUT . Provides an ECL - level clock
output during the Display Mode ( selected by jumper - connec
tor P300 ) .
Z - AXIS INPUT . Provides an input to intensify a crt display
via the front - panel Z BLANK OUT connector .
E
DISPLAY CLOCK
SWITCH
S835
Fig . 1-2 . Location of internal connectors and switches .
200
Co
Co
B
DATA
OUTPUT CONNECTOR
A
DATA INPUT CONNECTOR
BOTTOM
OF
UNIT
1967-12
RECORD ENABLE . Provides an input to set the memory
into a Store Mode .
EXT
DISPLAY
CLOCK INPUT
.
Provides
an input
to read
the
memory
with an
external
clock
signal ( ECL
level ) .
C External Clock Threshold Switch ( S848 )
ernal
Selects the external clock threshold level source . In the up
position ,
threshold
levels
are
selected by
front
-
panel
INPUT
switches VAR , TTL , or ECL . In the down position , a fixed
ECL
threshold
level is
selected .
@