Agilent Technologies 33120A Welding System User Manual


 
Theory of Operation
This chapter is organized to provide descriptions of the circuitry
contained on the schematics shown in chapter 8. A block diagram
overview is provided followed by more detailed descriptions of the
circuitry contained in the schematics chapter.
Block Diagram Overview . . . . . . . . . . . . . . . . 85
Output Attenuator . . . . . . . . . . . . . . . . . . . 86
Output Amplifier . . . . . . . . . . . . . . . . . . . . 87
AM Modulation . . . . . . . . . . . . . . . . . . . . . 89
Pre-attenuator . . . . . . . . . . . . . . . . . . . . . . 90
Square Wave and Sync . . . . . . . . . . . . . . . . . 90
Filters . . . . . . . . . . . . . . . . . . . . . . . . . . 92
Waveform DAC/Amplitude Leveling/Waveform RAM . . 93
Direct Digital Synthesis (DDS ASIC) . . . . . . . . . 95
System DACs . . . . . . . . . . . . . . . . . . . . . . 96
Floating Logic . . . . . . . . . . . . . . . . . . . . . . 97
Earth-Referenced Logic . . . . . . . . . . . . . . . . . 98
Power Supplies . . . . . . . . . . . . . . . . . . . . . 98
Display and Keyboard . . . . . . . . . . . . . . . . . . 100
The self-test procedures are described in chapter 6.
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