Philips pm2521 - Table of Contents

03
CONTENTS
Page
1.
CIRCUIT DESCRIPTION
1
1.1.
General
1
1 .2.
Survey of main sections 1
1.2.1.
Analog section 1
1 .2.2. Control
section
6
1 .2.3.
Display section 6
1.3.
Functional description
6
1.3.1.
General 6
1.3.2. Analog section (standard measurements)
7
1. 3.2.1.
Direct voltage measurements 7
1.3. 2.
2.
Alternating voltage measurements
8
1 .3.2.3.
Direct current measurements
9
1.3. 2.4. Alternating
current measurements
9
1.3.
2. 5.
Resistance measurements
10
1.3. 2.
6.
Diode measurements 11
1.3.2.
7.
Temperature
measurements
11
1
.3.3.
Analog section (extended measurements) 12
1.
3.3.1.
Frequency measurements
12
1.3.3.
2.
Time measurements
13
1. 3.3.3.
Trigger measurements 13
1.3.4. Analog section (multifunction circuits) 14
1. 3.4.1. R.M.S.
convertor 14
1.3.4. 2.
Impedance convertor
14
1.3.4.
3.
Active filter
15
1. 3.4.4.
Analog-to-Digital convertor 15
1.3.5.
Control section 17
1.3. 5.1.
Microprocessor
8035 17
1.3.5.
2.
Interrupt controller 21
1.3.5.
3.
Counter 22
1. 3.5.4.
Analog
control
22
1.3.5.
5.
ROM's
and Address/Data decoding
23
1.3.6.
Display section 23
1.4.
Detailed circuit description 26
1.4.1.
Measuring sequence 26
1.4. 1.1.
Initialisation 27
1.4.
1.2.
Internal test and adjust routine 28
1.4.
1.3.
Set up routine 31
1.4. 1.4.
Measurement routine 31
1.4. 1.5.
Calculation routine 32
1.4.
1.6.
Display output routine 32
1 .4.2.
Analog section (standard measurements)
33
1.
4.2.1.
Direct voltage measurements 33
1 .4.2.2. Alternating voltage
measurements
34
1 .4.2.3.
Direct current measurements
35
1.4. 2.4. Alternating
current
measurements
36
1 .4.2.5.
Resistance measurements
37
1.4.
2.
6.
Diode measurements
38
1.4. 2.
7.
Temperature measurements
38