Philips PM2519 - Page 19

2.1.
2-1
CIRCUIT DESCRIPTION
GENERAL
The circuit of the basic Automatic Multimeter PM 2519 can be subdivided into three main functional sections
as shown in Fig. 2.1.
— Analog section
— Digital section
— Display section
From the basic versions of the Automatic Multimeter the following type-numbers are derived:
— PM 2519/21 In the battery version (PM 2519/21) a rechargeable battery is used to supply the
instrument with power.
— PM 2519/51 The PM 2519/51 version has a galvanic separation and an IEC-625/IEEEE-488 bus
interface for digital output data and remote control.
Each of the sections is described separately in conjunction with the overall circuit diagrams (Fig. 7.1., 7.2.).
However, basic diagrams of the various stages are included, within the text, where considered necessary to
assist in a better understanding of the complex parts of the overall circuit.
INPUT ATTENUATORS FUNCTION SELECTION LCD DISPLAY
(:11.11AND 11.11 1000) MODE SWITCHES 000070 LCD DRIVER |? © COMPATIBLE
1¥ BECOMES 900 mv} MICROPROCESSOR
0Q0068 AC VOLTAGE-TO - MABB440 12 C COMPATIBLE
DC CURRENT CONVERTER 0Q0071 ADC INTERFACE 12 C COMPATIBLE
0QG063 PROGRAMMABLE CURRENT BUZZER
SOURCE 128 8-BIT STATIC RAM |2 C COMPATIBLE
0Q0067 BIFET INPUT ADC FREQUENCY DIVIDER
SHUNTS
INPUT TERMINALS
DIGITAL
SECTION
DISPLAY
SECTION
ANALOG
SECTION
POWER
SUPPLY
GALVANIC IEC-BUS
SEPARATION INTERFACE
BATTERY
PACK
OPTO COUPLERS MICROPROCESSOR MAB8440 2G COMPATIBLE
AMPLIFIERS ADDRESS SWITCHES
OCTAL BUS TRANSCEIVER WITH
3 STATE OUTPUTS
IEC BUS TRANSCEIVERS
Fig. 2.1. Basic built-up of PM 2519 stiaes
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