Agilent Technologies 6051A Manuel de service

SERVICE MANUALMultiple Input Electronic LoadMainframesAgilent 6050A and 6051APart No. 06050-90003Service ManualFor instruments with Serial Numbers:Agi

10GPIB BoardThis assembly contains static sensitive components. Observe all standard electrostatic procedures whenremoving or replacing the GPIB board

96 Replaces page 35Table 3-10 Secondary Microprocessor Signature AnalysisDescription: These signatures check secondary microprocessor U301 and latche

Replaces page 36 97Table 3-11. Main DAC, Transient DAC, Data Bus Sign

98 Replaces page 37Table 3-12. Transient Generator Signature Analysis (Secondary)Description: These signatures check transient generator IC's

Replaces page 38 99Table 3-13. Readback, Slew Rate, Analog Switch Sign

100 Replaces page 39Table 3-14. Chip Select, Status Readback, EEPROM Decoder Signature Analysis (Secondary)Description: These signatures check the c

101 Replaces page 41First, check that the SA waveforms shown on Figure 3-3 are correct. If these waveforms are not correct, check the SD0-7data bus l

102 Replaces page 42SLEW RATE SWITCH SETTINGSRefer to Module Operating Manual for Slew Rate Steps Slew Rate SLW1 SLW2 SLW3 SLW4#1HI HI LO HI#2HI L

Replaces page 43-45 103Figure 3-4. Slew Circuits Troubleshooting

104 Replaces page 46Figure 3-5. CC/CV Control Circuits Troubleshooting

Replaces page 47 105Input Power Stages Troubleshooting (Figure 3-6)There

11• When reinstalling the cable, be sure to line up the cable stripe over the hole marked with a square. Also, make sure thepins are all properly ali

106 Replaces page 48Transient Generator Troubleshooting (Figure 3-7)The transient generator (U310-U316) allows the input power stages to switch betwee

Replaces page 49 107Figure 3-7. Transient Generator Troubleshooting

108 Replaces page 54Overcurrent Circuit Troubleshooting (Figure 3-9)This circuit limits the maximum current the load can sink for different input volt

Replaces page 55 109Figure 3-9. Overcurrent Circuit TroubleshootingOverpo

110 Replaces page 56Figure 3-10. Overpower Circuit Troubleshooting

111IndexBBias supplies...

112Manual backdating...

12Note: On the Agilent 60504B/07B modules you must first disassemble the heatsink before you can access thedefective subassembly. First remove the thr

133TroubleshootingMost of the procedures described here are performed with power applied and protective covers removed.These procedures should be done

14Table 3-1 Test Equipment Required for TroubleshootingType Purpose Recommend ModelGPIB Controller Communicate with the load via the GPIB HP9825, Ser

15• Keep the work area free of non-conductive objects such as Styrofoam-type cups, polystyrene foam polyethylene bags,and plastic wrappers. Non-condu

16Figure 3-1. Overall Troubleshooting Flowchart (Sheet 1 of 3)

17Figure 3-1. Overall Troubleshooting Flowchart (Sheet 2 of 3)

18Figure 3-1. Overall Troubleshooting Flowchart (Sheet 3 of 3)

19Primary CircuitsThe turn-on selftest sequence of the primary microprocessor consists of two parts:1. The selftest is performed by the primary micro

CERTIFICATIONAgilent Technologies certifies that this product met its published specifications at time of shipment from the factory. AgilentTechnologi

20Table 3-2. Selftest Error CodeCode Error Description ProcedurePRIMARY PART 2 ERRORS-4 The primary microprocessor U203 read/write test tothe GPIB tal

21Test PointsTable 3-3 lists test points that are referred to in many of the troubleshooting procedures. Each test point is identified by acircled num

22Table 3-3. Test Points (continued)Test PointNumberSignal Measurement and Conditions U308-1CV PROG In VOLT MODE, + 10V with full rated voltage progr

23Table 3-3. Test Points (continued)Test PointNumberSignal Measurement and Conditions cath-D17+ OV + 14V when OV condition is false (normal). -13V wh

24Signature AnalysisNote: You cannot use signature analysis to troubleshoot units with the following serial numbers:Agilent 6050A: 3714A05433 and up;

25Test Header Jumper PositionsThe Electronic Load mainframe contains a primary test header (TP201) located on the GPIB Board, and each modulecontains

26The following paragraphs describe the setups for troubleshooting the mainframe GPIB Board, and the Control Board andPower Board in the load modules.

27AC mains voltage is present on exposed pins on the top edge of the mainframe GPIB Board and eachmodule whenever the unit is turned on.a. Carefully

28Figure 3-2. Signature Analysis Setup

29Table 3-4. Primary Microprocessor Signature AnalysisDescription: These signatures check primary microprocessor U203, ROM U205, and RAM U206. The si

SAFETY SUMMARYThe following general safety precautions must be observed during all phases of operation, service and repair of thisinstrument. Failure

30Table 3-5. GPIB Interface Signature Analysis (Primary)Description: These signatures check the GP-IB talker/listener IC U202. The signatures are val

31Table 3-6. Front Panel Interface Signature Analysis (Primary)Description: These signatures check the front panel interface IC's U246 U209, U21

32Table 3-7. Trigger Circuit Signature Analysis (Primary)Description: These signatures check the operation of the primary trigger circuits. The signa

33Table 3-7. Trigger Circuit Signature Analysis (Primary) continuedU228 - connect CLOCK = TP201-16 (CS7)U228-1 = UFP6 +5V U228-11 = OOOO Pulsing LOU2

34Table 3-9. Fan Speed Control Signature Analysis (Primary)Description: These signatures check the fan speed control circuits. Connect the signature

35Table 3-10. Secondary Microprocessor Signature AnalysisDescription: These signatures check secondary microprocessor U301 and latches U302 and U330

36Table 3-11. Main DAC, Transient DAC, Data Bus Signature Analysis (Secondary)Description: These signatures check main DAC U320, transient DAC U32

37Table 3-12. Transient Generator Signature Analysis (Secondary)Description: These signatures check transient generator IC's U350 through U35

38Table 3-13. Readback, Slew Rate, Analog Switch Signature Analysis (Secondary)Description: These signatures check the readback DAC U322, slew rate

39Table 3-14. Chip Select, Status Readback, EEPROM Decoder Signature Analysis (Secondary)Description: These signatures check the chip select IC U304

DO NOT CIRCUMVENT SAFETY DEVICES.AC mains power exists on exposed terminals in various locations in the mainframe and on the load modules. To protect

40Figure 3-3. DAC Circuits Troubleshooting

41If the unit has failed selftest by reporting an error 105-108 at turn-on and no problem can be found using SA, the IMONadjustment may be at fault.

42SLEW RATE SWITCH SETTINGS Refer to Module Operating Manual for Slew Rate Steps Slew Rate SLW1 SLW2 SLW3 SLW4#1 HI HI LO HI#2 HI LO LO HI#3 LO HI L

43Figure 3-4A. Slew Circuits Troubleshooting for 60501B

44Figure 3-4B. Slew Circuits Troubleshooting for 60502B/04B/07B

45Figure 3-4C. Slew Circuits Troubleshooting for 60503B

46Figure 3-5. CC/CV Control Circuits Troubleshooting

47Input Power Stages Troubleshooting (Figure 3-6)There are four, eight or sixteen identical input power stages (depending on the module) connected in

48FSEL TABLEFront Panel FSEL INPUTSinterval between 1µµµµs pulsesFrequency 0 1 2 @U350-14 @U351-1410000Hz LO LO LO LO50µs1000Hz HI LO LO10µs 500µs100

49Figure 3-7. Transient Generator Troubleshooting

5Table Of ContentsIntroduction ...

50Toggle or Pulse ModesTo check the transient generator in toggle and pulse modes, run the following program:10 LOOP20 OUTPUT 705;"TRAN ON;:TRAN:

51Trigger Circuit Troubleshooting (Figure 3-8)The Multiple Electronic Load can be triggered over the HPIB using the GET function, the *TRIG common com

52Level Triggers (*TRG and TRIG command)The following program continuously toggles all labeled signal lines in Figure 3-8 in the indicated direction.1

53Figure 3-8. Trigger Circuit Troubleshooting

54Overcurrent Circuit Troubleshooting (Figure 3-9)This circuit limits the maximum current the load can sink for different input voltages and/or power

55Figure3-9. Overcurrent Circuit TroubleshootingOverpower Circuit Troubleshooting (Figure 3-10)This circuit limits the power sinking capability of th

56Figure 3-10. Overpower Circuit TroubleshootingFan Speed Control Troubleshooting (Figure 3-11)Use extreme caution when troubleshooting the GPIB boar

57Checking the waveform across U242 pins 4-6 involves circuits that are connected to the ac mains. To lessenthe danger of personal injury, the mainfra

58Figure 3-11. Fan Speed Control Circuit Troubleshooting

59Post Repair CalibrationCalibration is required annually and whenever certain components are replaced. If certain control board components(U13-16, U3

6Post Repair Calibration...

614Principles Of OperationIntroductionFigure 4-1 is a block diagram illustrating the major circuits and signals within the Electronic Load. Each block

62the ac line-synchronization signal derived from the Bias Supply circuits. TRIG_IN is derived from the external triggersignal connected to the rear p

63Figure 4-1. Block Diagram (Sheet 1 of 3)

64Figure 4-1. Block Diagram (Sheet 2 of 3)

65Figure 4-1. Block Diagram (Sheet 3 of 3)

66Power Board CircuitsThe CV Control circuit compares CV_PROG, which represents what the input voltage should be, to VMON*, whichrepresents what the i

67Figure 4-2. Module/Mainframe Communication

695Replaceable PartsIntroductionTable 5-4 lists the electrical components and Table 5-5 lists the mechanical components for the Agilent 6050A/6051AEle

71IntroductionScopeThis manual contains information for troubleshooting and repairing the Electronic Load mainframe and modules to thecomponent level.

70Table 5-2. Part Description AbbreviationsAL Aluminum PE PolyesterCC Carbon Composition PD Power DissipationCER Ceramic PP PolypropyleneDIP Dual In-

71Table 5-4. Agilent 6050A/6051A Parts List - ElectricalRef.Desig.HPPart No. DescriptionMfr.CodeMfrPart No.A3 5063-3440GPIB BOARD ASSEMBLY28480C201 0

72Table 5-4. Agilent 6050A/6051A Parts List - Electrical (continued)Ref.Desig.HPPart No. DescriptionMfr.CodeMfrPart No.L200,201 06050-80002 CHOKE, RF

73Table 5-4. Agilent 6050A/6051A Parts List - Electrical (continued)Ref.Desig.HPPart No. DescriptionMfr.CodeMfrPart No.R276 0683-1815 RESISTOR 180 5%

74Table 5-4. Agilent 6050A/6051A Parts List - Electrical (continued)Ref.Desig.HPPart No. DescriptionMfr.CodeMfrPart No.TP201 1251-4927 CONNECTOR-POST

75Table 5-4. Agilent 6050A/6051A Parts List - Electrical (continued)Ref.Desig.HPPart No. DescriptionMfr.CodeMfrPart No.06050-600026050A FRONT PANEL A

76Table 5-5. Agilent 6050A/6051A Parts List - Mechanical (continued)Ref.Desig.HPPart No.QuantityDescriptionFRONT PANEL ASSEMBLYMP11 5040-5448 1 WINDO

77Table 5-5. Agilent 6050A/6051A Parts List - Mechanical (continued)Ref.Desig.HPPart No.QuantityDescriptionMP326050A 06050-00012 1 SHROUD-FAN6051A 06

78Figure 5-1. Mechanical Parts Locations

79Figure 5-1. Mechanical Parts Locations

8Safety ConsiderationsThe Electronic Load is a Safety Class 1 instrument that has a protective earth terminal. Refer to the Safety Summary page atthe

806DiagramsIntroductionThis chapter contains the test point and component location diagram, schematic diagrams, and related tables useful formaintenan

81Table 6-1. Signal-Name DescriptionsMnemonic Function Sheet 1 Sheet2Sheet 3GPIB BOARDCAL_LOCK Software-calibration lockout (D)8C4ACLR Initialize tran

82Table 6-1. Signal-Name Descriptions (continued)Mnemonic Function Sheet 1 Sheet 2 Sheet 3PTX1 \5B, 8APTX2 |5B, 8APTX3 |5B, 8APTX4 |---- Se

83Figure 6-1. Keypad WiringTable 6-2. Component LocationsCOORDINATES COORDINATES COORDINATES COORDINATES COORDINATES COORDINATES COORDINATES"A&

84Table 6-3. Schematic Diagram Notes1. All resistors are in ohms ±1%, 1/8 W, unless otherwise specified.2. All capacitors are in microfarads unless ot

85AManual BackdatingThis section describes changes that must be made to the manual so that it applies to instruments with serial numbers lowerthan tho

9 2Disassembly ProceduresIntroductionThe following procedures will make it easier for you to disassemble major components on the Electronic Load main

86Table 3-4. Primary Microprocessor Signature AnalysisDescription: These signatures check primary microprocessor U203, ROM U205, and RAM U206. The si

87Table 3-5. GPIB Interface Signature Analysis (Primary)Description: These signatures check the GP-IB talker/listener IC U202. The signatures are val

88Table 3 6. Front Panel Interface Signature Analysis (Primary)Description: These signatures check the front panel interface IC's U246 U209, U21

89Table 3-7. Trigger Circuit Signature Analysis (Primary)Description: These signatures check the operation of the primary trigger circuits. The signa

90Table 3-7. Trigger Circuit Signature Analysis (Primary) continuedU228 - connect CLOCK = TP201-16 (CS7)U228-1 = UFP6 +5V U228-11 = OOOO Pulsing LOU2

91Description: These signatures check the fan speed control circuits. Connect the signature analyzer's clock input to theIC under test as specif

93B"A" Load Modules TroubleshootingThis section describes the changes that must be made to the troubleshooting procedures in section 3 of th

94 Replaces page 22Table 3-3. Test Points (continued)Test PointNumberSignal Measurement and ConditionsU308-1CV PROG In VOLT MODE, + 10V with full rat

Replaces page 23 95Table 3-3. Test Points (continued)Test PointNumberS