Fluke 5720A service manual Theory of Operation

Theory of Operation 2

Introduction

2-98.	Internal CAL Zero Amplifier	2-59
2-99.	Switch Matrix 5725A Amplifier Interface	2-61
2-100.	DAC Assembly (A11)	2-61
2-101.	Basic DAC Theory of Operation	2-61
2-102.	DAC Assembly Digital Control	2-64
2-103.	DAC Assembly Reference Circuitry	2-64
2-104.	Duty-Cycle Control Circuit	2-65
2-105.	DAC Filter Circuit	2-66
2-106.	DAC Output Stage	2-66
2-107.	Sense Current Cancellation Circuit	2-67
2-108.	Linearity Control Circuit	2-67
2-109.	Negative Offset Circuit	2-68
2-110.	DAC Output Switching	2-68
2-111.	DAC Buffered Reference Sip	2-68
2-112.	Calibration Hardware	2-69
2-113.	ADC Amplifier	2-69
2-114.	ADC Input Selection	2-69
2-115.	ADC Circuit	2-70
2-116.	How the DAC is Used in Calibration	2-72
2-117.	DAC Assembly Calibration	2-72
2-118.	Oscillator Section Overview	2-73
2-119.	Oscillator Control Assembly (A12)	2-73
2-120.	Oscillator Control Digital Control	2-74
2-121.	Oscillator Input Switching	2-74
2-122.	Sense Current Cancellation	2-74
2-123.	Averaging Converter	2-75
2-124.	Error Integrator	2-75
2-125.	Three-Pole Filter	2-75
2-126.	Analog Amplitude Control Loop	2-75
2-127.	AC/DC Thermal Transfer Circuit	2-77
2-128.	Oscillator Calibration	2-79
2-129.	AC/DC Frequency Response Characterization	2-80
2-130.	Oscillator Output Assembly (A13)	2-80
2-131.	Oscillator Output Digital Control	2-82
2-132.	Quadrature RC Oscillator	2-82
2-133.	Oscillator Amplitude Control	2-83
2-134.	Phase−locked Loop	2-83
2-135.	2.2V and 22V Range Output Amplifier	2-84
2-136.	Oscillator Wideband Smd Assembly (A13A1)	2-84
2-137.	Output Stage	2-85
2-138.	Phase Shifter	2-85
2-139.	Power Amplifier Assembly (A16)	2-85
2-140.	Power Amplifier Digital Control Sip Assembly (A16A1)	2-86
2-141.	PA Common Circuitry	2-87
2-142.	+PA and -PA Supplies	2-87
2-143.	PA Input Stage	2-87
2-144.	PA Mid Stage	2-88
2-145.	PA Output Stage	2-88
2-146.	PA Sense Current Cancellation Circuitry	2-89
2-147.	PA in Standby	2-89
2-148.	PA Operation: 220V DC Range	2-89
2-149.	PA Operation: 220V AC Range	2-91
2-150.	High Voltage Assembly Support Mode	2-91
2-153.	220V DC Internal Calibration Network	2-92
2-154.	PA Calibration	2-92

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