Instruction/ maintenance manual of the product 6681A Agilent Technologies
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SERVICE MANUAL GPIB DC Po wer Sup plie s Agilent Series 668xA For instruments with Seria l Numbers: Agilent M odel 6680 A : US36480 101 and A bove * Agilent M odel 6681 A : US36400 101 and A bove * Ag.
2 CERTIFICATION Agilent Technologies certifies that this product met its published specifications at time of shipment from the factory. Agilent Technologies further cer tifies that its calibration mea.
3 SAFETY CONSIDERATIONS GENERAL. This is a Safety Class 1 instrument (provided with terminal for connection to pr otective earth ground). OPER A T ION. B EFORE APPLYING POWER verify that the pro duct is set to match the available line voltage, the correct line fuse is installed, and all sa fety precautions (see follo wing warnings) are taken.
4 Safety Sy mbol Definitions Symbol Description Symbol Description Direct current Terminal for L ine conductor on perm a nently installed equip m ent Alternating current Caution, risk of electric shoc.
5 Table of Contents Introduction ............................................................................................................................................................................ 7 Scope......................................
6 Post-Repair Ca libration ........................................................................................................ ............................................. 62 When R equired .......................................................
Introduction 7 1 Introduction Scope Organization This manu al contains information for troublesh ooting and repairing t o the componen t level Agil ent Series 668x A, 5-kilowatt power supplies.
Introduction 8 Related Docume nts Change Sh eet There may or may not be a Manual Cha nge sheet in cluded with this manual (see Manual Revision s). If one is in cluded, be sure to examine it for changes to this manual.
Introduction 9 Safety Considerations This po w er supp ly is a Safety Class I instrument, which means it has a p rotective earth terminal. This terminal must be connected to earth ground th rough a power s ource equipped w i th a 4- w ir e, groun d receptacle.
Verificatio n 11 2 V erification Introduction This chapte r provides te st procedures for check ing the operati on of Agi lent Series 668xA power s upplies . The required tes t equipment is s pecified and sam ple performance test record sh eets are included.
12 Verif ication Table 2- 1. Test Equip ment Requir ed Ty pe Required Character istics Recommended Model Digital Volt m eter 1 Resolution : 10 nV @ 1V Agilent 3458A Readout : 8 1/2 dig its Accuracy : 20 pp m Current Monitor Resistor 1 Agilen t 6682A, 6683A , Agilent 6684A : Guil dline 9230/30 0 0.
Verificatio n 13 Programming The Tests General Considerations Procedures are gi ven for programm ing these tests either from th e front panel key pad or from a GPIB controller. The procedures as sume y ou know how to use th e front pane l keypad or how to program over the G PIB (see the Pow er Supply Operating Manual for more information).
14 Verif ication Operation Verification Tests Table 2-3 lists the requirements for op eration verif ication, which is a subset of the perfor m a nce tests.
Verificatio n 15 Figure 2-1. Constant Voltage (C V) Test Setu p.
16 Verif ication Table 2- 4. Constant Voltage (CV) Tests Acti on Normal Result Voltage Program min g and Readb ack Accuracy This tes t verif ies that th e voltage prog ramming, G PIB readback (GPI B system power suppl ies only ), and fron t panel display functions are within s pecifications.
Verificatio n 17 Table 2- 4. Constant Voltage (CV) Tests (con tinued) Acti on Normal Result CV Source Effect (cont) 2 Set the transformer to the nominal ac line voltage.
18 Verif ication Table 2- 4. Constant Voltage (CV) Tests (con tinued) Acti on Normal Result Transient Recovery Tim e This test measures the time required for the output voltag e to return to w ithin 100mV of its final value follo w ing a 50% change in ou tput load current.
Verificatio n 19 Constant Current (CC) Tests Test Set up Connect the appropriate cu rrent monitoring resist or (see Table 2-l) as sh own in Fig. 2-3. The accuracy o f the resistor mus t be as specified in the table. Test Pro cedures The test procedures are g iven in Table 2-5.
20 Verif ication Table 2-5. Constant Current (CC) Tests (continue d) Action Normal Result CC Noise (PARD) (cont) 2 Measure the residu al noise on the DVM with the pow er supply tu rned off. Noise generated by other equipment may affect this measurement and should be rem o v ed or factored ou t.
Verificatio n 21 Table 2-5. Constant Current (CC) Tests (continue d) Action Normal Result CC Source Effect This test measures the change in outpu t cu rrent resulting from a change in ac line voltage from its minimum to its maximum value within the line v oltage specifications.
22 Verif ication Figure 2-3. CC Load Eff ect Test Set up.
Verificatio n 23 Figure 2-4. CC rms Noise T est Setup.
24 Verif ication Av eraging the CC Measurement s The CC Load Eff ect and CC Source Effect tests m easure the dc regulation of the power supply's ou tput current. When doing these tests, you mu st be sure that the readings taken are truly dc regulatio n v alues and not insta ntaneous ac peaks of the output cu rrent ripple.
Verificatio n 25 Table 2- 6. Performan ce Test Record Form Test Facility : __________________________________________ Report No.__ _________ ____________ _________ __________ _________________________.
26 Verif ication Table 2- 7. Performan ce Test Record for A gilent M odel 6680 A MODEL Agilen t ___________ __ Report No._ ____________ _ Date_____ ___________ _____ Test Descrip tion Mi nim um Spec.
Verificatio n 27 Table 2- 7. Performan ce Test Record for A gilent M odel 6681 A MODEL Agilen t___________ __ Report No._ ____________ _ Date_____ ___________ _____ Test Descrip tion Mi nim um Spec.
28 Verif ication Table 2- 7. Performan ce Test Record for A gilent M odel 6682 A MODEL Agilen t___________ __ Report No._ ____________ _ Date_____ ___________ _____ Test Descrip tion Mi nim um Spec.
Verificatio n 29 Table 2- 7. Performan ce Test Record for A gilent M odel 6683 A MODEL Agilen t___________ __ Report No._ ____________ _ Date_____ ___________ _____ Test Descrip tion Mi nim um Spec.
30 Verif ication Table 2- 7. Performan ce Test Record for A gilent M odel 6684 A MODEL Agilen t___________ __ Report No._ ____________ _ Date_____ ___________ _____ Test Descrip tion Mi nim um Spec.
Troubleshooting 31 3 T rouble shooting Shock Hazard : Mos t of th e procedures in this chapte r must be perf ormed wi th power appli ed and protective covers removed. These procedu res sh ould be done on ly by trained s ervice personn el aware of the hazard f rom electrical shock.
32 Troubleshooting Test Equipment Required Table 3- 1. Test Equip ment Requir ed Equipment Purpose Recommended Model Logic Probe To check s tates of data l ines. Agil ent 545A Test Clips To gain access to IC pin s. AP Products No. LTC Ammete r/Curren t Shunt To me asure out put current.
Troubleshooting 33 Table 3- 2. Selftest Error Code s/Messages Code and/or Messag e Descriptio n Probabl e Cause Selftest Error Codes/M essages El FP RAM Front panel RAM test failed (po w er-o n). Microprocesso r A lU3 E2 FP ROM Front panel ROM test failed (po w er-on and * TST?).
34 Troubleshooting Troubleshooting Charts Figure 3-1 gives overall troubleshooting pr ocedures to isolate the fault to a circuit board or particular circuit (see Figure 3-20 for th e location of th e circuit boards).
Troubleshooting 35 Figure 3-1. Overall Troubleshooting (Sheet 1 of 4).
36 Troubleshooting Figure 3-1. Overall Troubleshooting (Sheet 2 of 4).
Troubleshooting 37 Figure 3-1. Overall Troubleshooting (Sheet 3 of 4).
38 Troubleshooting Figure 3-1. Overall Troubleshooting (Sheet 4 of 4).
Troubleshooting 39 Figure 3-2. No Display Troubleshooting.
40 Troubleshooting Figure 3-3. OV Will Not Fire Troubleshooting.
Troubleshooting 41 Figure 3-4. OV At Turn-On Troubleshooting.
42 Troubleshooting Figure 3-5. Output Held Low Troubleshooting (Shee t 1 of 2).
Troubleshooting 43 Figure 3-5. Output Held Low Troubleshooting (Shee t 2 of 2).
44 Troubleshooting Figure 3-6. Output Held High Troubleshooting.
Troubleshooting 45 Figure 3-7. DAC Circuits Troubleshooting.
46 Troubleshooting Figure 3-8. DAC Test Wav eforms.
Troubleshooting 47 Figure 3-9. CV/CC DAC and Amplifier Circuit Troubleshooting.
48 Troubleshooting Figure 3-10. Serial Down Troubleshooting (Sheet 1 of 2).
Troubleshooting 49 Figure 3-10. Serial Down Troubleshooting (Sheet 2 of 2).
50 Troubleshooting Figure 3-11. Secondary Interface Down (Sheet 1 of 2).
Troubleshooting 51 Figure 3-11. Secondary Interface Down (Sheet 2 of 2).
52 Troubleshooting Figure 3-12. Slow Downprogramming Troubleshooting.
Troubleshooting 53 CV/CC Status Annunciators Troubleshooting When troubleshooting t he C V/CC status annunciators or status readback circu its, firs t measure the voltage drop across th e gating diodes, wh ich are Al0D651 f or the C C circuit and A l0D652 for the CV circu it (see A10, Sheet 2).
54 Troubleshooting Table 3-4. FET Troubleshooting Chart (continue d) Procedure Res ult Dyna m ic Trouble shooting 1. Turn off the power supply and rem ove the A3 FET Board with its heat sink assembl y.
Troubleshooting 55 Figure 3-13. A3 FET Board Test Waveforms.
56 Troubleshooting Signature A nal y sis Introduction The easiest and most eff icient method of troubl eshooti ng microprocess or-based i nstrument s is with signature an alysis (SA ). This technique is si milar to signal tracing with an oscilloscope in linear circuits.
Troubleshooting 57 Test Header s The power su pply has two tes t headers as shown in Figure 3-15, each w ith a jumper that can be moved to diff erent positions for SA testing and for other functions. To gain access to the headers, re m ove t he pow er supply top cover.
58 Troubleshooting Table 3- 5. Primar y Interface S A Test Description : These signatures ch eck some primary interface circu its on the Systems Supply A2 GPIB Board. Valid A2U106 R OM Firm ware Revision: A .01.06 Test Setup: See Figure 3-17. 1. Turn of f the pow er supply and rem ove the top cov er.
Troubleshooting 59 Figure 3-1 6. Signature Analysis Connections, (Sheet 1 of 2).
60 Troubleshooting Figure 3-1 6. Signature Analysis Connections, (Sheet 2 of 2) Table 3-6. Front Panel SA Test Description : These signatures ch eck front panel microprocessor A lU3. Valid A1U4 ROM Fir m w are Revision: A.01.07 Test Setup: See Figure 3-17.
Troubleshooting 61 Table 3-7. Secondary Interface SA Test Description : These signatu res check the secon dary microprocessor A 5U504. Valid A5U504 R OM Firm ware Revision: A .01.04 Test Setup: See Figure 3-17. 1. Turn of f the pow er supply and rem ove the top cov er.
62 Troubleshooting Post-Repair Ca libration When Required Calibration is requ ired annually and also when ever certain components are replaced. If com ponents in any of the circuits listed below are replaced, th e supply must be recalibrated. Note For calibration procedures, s ee Appendix A of the Operating Manu al.
Troubleshooting 63 EEPROM Initia lization EEPROM A lU6 on the A1 F ront Pan el Board stores the su ppl y' s GPIB address, m odel number, an d constants requ ired to program and calibrate the power su pply.
64 Troubleshooting 10 ! Program to initiali ze EPROM or mov e factory pres et data in 668xA 20 ! power su pplies . 30 ! RE-S TORE " INIT_66 8X" 40 ! Rev A .
Troubleshooting 65 510 DATA 115,30,20,1,127,. 002701,.2,.000 42,10.25 520 ! 530 Eprom _data_6684: ! ! EEPRO M data for 6684A 540 DATA 93,74,41,0,83, 0,29,70, 131,0 550 DATA 98,21,4.6,10,5 0,0,83, 255,20, 10 560 DATA 6684,87,97,2 8,93,128,5, 255,0,0 570 DATA 1296,6684,0,20,1 80,20,180,1 75,33,98 580 DATA 115,30,20,1,127,.
66 Troubleshooting 1020 GOSUB Ps_error ! Error if passcode i s not "0"! 1030 IF Err THEN 1040 OUTPUT @Ps ;"*IDN ?" ! Get data f rom model # l ocation 1050 ENTER @Ps ;Idn$ 1060 Mode.
Troubleshooting 67 1530 CLEAR SCREEN 1540 PRINT "This program should ONLY be com pleted if your pow er supply ” 1550 PRINT "EEPROM has been replaced or a com ponent that will effect" .
68 Troubleshooting 2010 IF Err THEN 2020 PRINT "A n error occurred du ring the EEPRO M read/wri te, Check for" 2030 PRINT "program ming errors. In itialization data may be in correct." 2040 STOP 2050 END IF 2060 ! 2070 PRINT "Operat ion com plete.
Troubleshooting 69 Top Cover 1. Remove the fou r screws that secure the carry ing straps (tw o TORX 20 screws on each side). These s ame screw s secure the cover to the chas sis. 2. Spread the bottom rear of the cover, and then pull the cov er backwards towards the rear of th e power supply to disengage it from the front panel.
70 Troubleshooting A 4 AC Input Assembly To remove the A4 AC Input Board first remov e the GPIB board then disconn ect these cables from the following connectors at the GPIB board: 1. Disconn ect the cables going to connector J417 and J420. 2. Disconn ect the cable g oing to conn ector J419.
Troubleshooting 71 A 10 Control A ssembly Disconnect the cables from the following connectors at the A10 DC RAIL board: 1. Disconn ect the ribbon cable goin g from t o the A6 Bias board. This cabl e connects t o J509 on th e A10 board bu t it is easier to disconn ect it at the A6 Bias Board.
72 Troubleshooting A 1DSP 1 LCD Display 1. Remove t he A1 Front Pan el Board as des cribed i n that procedure. 2. Remove t he nuts s ecuring the LC D display to th e fron t panel ass embly and rem ove the LCD and at tached ribbon cabl e (see CAUTION below ).
Troubleshooting 73 Figure 3-18. Component Locations (Top Cover and RFI Shield Removed).
74 Troubleshooting Figure 3-1 9. 5-Inch Front Panel Frame A ssemb ly.
Troubleshooting 75 Figure 3-20. 3-Inch Front Panel Frame Assembly.
76 Troubleshooting Figure 3-21. Assembly A10, Exploded View.
Troubleshooting 77 Figure 3-2 2. Assembly A10, Exploded View (668 0A, 6681 A ).
78 Troubleshooting Figure 3-2 3. Assembly A10, Exploded View (668 2A, 6683 A , 6684 A ).
Troubleshooting 79 Figure 3-2 4. Three-Ph ase Line Ch oke Subch assis Wirin g.
80 Troubleshooting Figure 3-25. 24 Volt Fan Transformer.
Principles O f Operation 81 4 Principles Of Operatio n Introduction Figure 4- 3 (at th e end of t his chapter) is a block diag ra m sh owing the m aj or circu its wi thin the pow er supply . The pow er supply consists of the following circuits: • A1 Front Panel Board ckts.
82 Prin ciples Of Op eration A digital cont rol interface on the A2 GPIB Board prov ides the following power supply fun ctions: • Relay lin k. • Digital 1/0. • Remote inhibit (INH). • Discrete fault indicator (FL T). An optical isolator IC (U113) isolates the FL T output si gnal common f rom the external fault circuit comm o n.
Principles O f Operation 83 The Secondary Microproces sor translates serial data receiv ed from the A2 board into parallel 12 bit data. The data bus is connected directly to the four DAC/OpAmp circuits. Under con trol of the lip the s elected DAC converts the bus data into an analog s ignal.
84 Prin ciples Of Op eration any value of load impedance. Sw itching between CV and CC is don e automatically by the CV/CC control circuits at a value of load im pedance equal to th e ratio of the programm ed voltage value to the prog ramm ed current value.
Principles O f Operation 85 A 4 A C Input Board The A4 Inpu t Board contains t he Inrush- Current Limi t relay (K 401), Main Pow er Relay (K402), current-li miting resi stors (R407, R408 ) and open- fu se-det ect resistor circui t (R400- R405).
86 Prin ciples Of Op eration Figure 4-2. 1ST Stage of the FET H-Bridge Configuration Output Circuits The output circuits include the following circuits: • Chassi s m oun ted compo nents. • Two pow er transf or me rs, T900/T901 . • Two in d uctors , L900/ L901.
Principles Of Operatio n 87 Figure 4-3. Agilent Series 668xA Power Supply, Block Diagram.
Replaceable Parts 89 5 Replace able Part s INTRODUCTION Chapter Organization This section lists the replaceable electrical an d mechanical parts for th e Agilent 668xA series power s upplies.
90 Replac eable Parts How to Order Parts You can order parts from you r local Agilent Technol ogies, In c. Sales and Support Office (see t he list of offices in th e back of this manual).
Replaceable Parts 91 Table 5- 3. Main Chassi s, Replaceable Parts Ref. Desig. Agilent Part No. Description C907 6680A 0180-4 516 CAP 3300 0uF 7.5V 6681A 0180-4 532 CAP 2200 0uF 16V 6682A 0180-4 615 CAP 1800 0uF 28V 6683A 0180-4 596 CAP 1300 0uF 45V 6684A 0180-4 597 CAP 7.
92 Replac eable Parts Table 5- 3. Main Chassi s, Replaceable Parts (con tinued) Ref. Desig. A gilent P art No. Description 2110-091 0 FUSE (s ee 5060-3513 ) 2110-091 1 FUSE (s ee 5060-3512 ) 3160-0 41.
Replaceable Parts 93 Table 5- 3. Main Chassi s, Replaceable Parts (con tinued) Ref. Desig. A gilent P art No. Description 1400-06 11 CABL E CLAM P (GPIB/F AN ) 5080-2 299 LABEL REAR PAN EL 5080-241 3 .
94 Replac eable Parts Table 5- 4. A1 Front P anel Board, Rep laceable Part s (continued ) Ref. Desig. A gilent P art No. Description S1 3101-308 8 Line sw itch VR16 1902-095 0 Diode Zen er 4.
Replaceable Parts 95 Table 5- 6. A2 GPIB Board , Replace able Parts (se e Note) Ref. Desig. Agilent Part No. Description ELEC TRICAL PAR TS C122 0180-4 606 C apacitor 10,000 µ F C128 0160-4 281 Capac.
96 Replac eable Parts Table 5- 7. A3 FET A s sembly, Repla ceable Parts ( continued ) Ref. Desig. A gilent P art No. Description C244, 245 0160-680 6 CAP .lu F 400V C248 0160-4 832 CAP .0lu F 10% C258 0180-4 132 CAP 6.8u F 35V C301 0160-750 5 7uF+ - 5% 200V C302 0180-4 132 CAP 6.
Replaceable Parts 97 Table 5- 7. A3 FET A s sembly, Repla ceable Parts ( continued ) Ref. Desig. A gilent P art No. Description Q301, 302, 303, 304 1855-085 9 MOSFET 500V 20A Q311, 322, 333, 344 1855-085 9 MOSFET 500V 20A Q351, 352, 353, 354 1853-0 363 D45H5/D45H8/ 363 R201 0811-390 3 RES 150 O hm 5W N I R202 0699-020 8 RES 1 5% .
98 Replac eable Parts Table 5- 7. A3 FET A s sembly, Repla ceable Parts ( continued ) Ref. Desig. A gilent P art No. Description R271 0757-020 0 RES 5.62K 1% R272 0757-044 2 RES l0K 1% .125W R273, 274, 2 75 0757-043 7 RES 4.75K 1% R277 0698-363 3 RES 3905% 2W MO R301 0811-390 3 RES 150O hm 5W N I R302 0699-020 8 RES 1 5% .
Replaceable Parts 99 Table 5- 7. A3 FET A s sembly, Repla ceable Parts ( continued ) Ref. Desig. A gilent P art No. Description R383 0757-044 2 RES 10K 1% .
100 Repla ceable Part s Table 5- 9. A5 DC Rail A s sembly, Rep laceable Parts Ref. Desig. Agilent Part No. Description ELEC TRICAL PAR TS C418 0160-40 48 CAP 0.02 2uF 20% C420, 421, 4 22 0160-7 606 CAP lu F 275V C427 0160-774 3 C-F .047u F 380V D420, 421, 422, 424, 4 25 5060-351 6 ASSY.
Replaceable Parts 10 1 Table 5- 10. A6 Bias A ssembl y, Replaceabl e Parts (con tinued) Ref. Desig. Agilent Part No. Desc ription C823 0180-4 131 CAP 4.
102 Repla ceable Part s Table 5- 10. A6 Bias A ssembl y, Replaceabl e Parts (con tinued) Ref. Desig. Agilent Part No. Desc ription R842 0698-6 360 RES 10K .1% R843 0757-0 472 RES 200K 1% R844 0698-6 977 RES 30K .1% .125 R845, 847 0698-6360 RES 10K .1% R848 0698-6 977 RES 30K .
Replaceable Parts 10 3 Table 5-11. A 7 Snubber A ssembl y , Replaceabl e Parts Ref. Desig. Agilent Part No. Desc ription ELEC TRICAL PAR TS C910, 911, 9 12, 913 6680A, 668 1A 0160- 016 2 CAP .
104 Repla ceable Part s Table 5- 13. A9 Down Programmer/Slo w Sense, Rep laceable Part s Ref. Desig. Agilent Part No. Desc ription ELEC TRICAL PAR TS C950, 951 0160-425 9 CA P .22uF 10% C952, 953 0160-404 8 CA P .022uF 20% C956, 957 0160-4065 CAP .lu F 20% C958, 980 0160-4835 CAP .
Replaceable Parts 10 5 Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts Ref. Desig. Agilent Part No. Desc ription ELEC TRICAL PAR TS C500, 501, 5 02 0180-4129 CAP l uF 35V C503 0160-4 835 CAP .l uF 10% 50V C504 0180-4 129 CAP luF 35V C505 0180-4 131 CAP 4.
106 Repla ceable Part s Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription C588 0160-4 799 CAP 2.
Replaceable Parts 10 7 Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription C639 0160-4 795 CAP 4.7pF C640 0160-4 835 CAP .l uF 10% 50V C641 0160-5 410 CAP 3300pF 5% C645 0160-4 805 CAP 47pF 5% l00V C648 0160-4 831 CAP 4700pF 10% C650 0160-4 833 CAP .
108 Repla ceable Part s Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription R506 0757-0 289 RES 13.3K 1% R507 0698-3 155 RES 4.64K 1% R508 0698-6 323 RES 100.1% R509 0757-0 442 RES 10K 1% .125W R510 0757-0 289 RES 13.
Replaceable Parts 10 9 Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription R570, 580 0757-0424 RES l.lK 1% R581 0757-0 407 RES 200 1% .125W R582, 583 0698-4486 RES 24.9K 1% R584 0757-0 472 RES 200K 1% R585 0757-0 434 RES 3.
110 Repla ceable Part s Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription R624 0757-0 453 RES 30.1K 1% R625 6680A, 668 1A 0698- 3455 RES 261K 1% 6682A 0757-0 461 RES 68.1K 1% 6683A, 668 4A 0699- 1972 RES 1.
Replaceable Parts 11 1 Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription R666 6680A 0698-891 3 RE S 1.5M 1% 6681A, 668 2A 0683- 2255 RES 2.2M 1% 6683A 0683-475 5 RE S 4.7M 1% 6684A 0683-565 5 RE S 5.
112 Repla ceable Part s Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription R684 6680A 0757-0 280 RES lK 1% 6681A 0757-0 289 RES lK 1% 6682A 0757-0 430 RES 2.21K 1% 6683A 0698-3 496 RES 3.57K 1% 6684A 0757-0 436 RES 4.
Replaceable Parts 11 3 Table 5- 14. A10 Cont rol Assembly, Rep laceable Pa rts (contin ued) Ref. Desig. Agilent Part No. Desc ription R709 6680A 0757-0 468 RES 130K 6681A, 668 2A 0757- 0464 RES 90.9K 6683A, 668 4A 0757- 0464 RES 90.9K R710 6680A 0698-5 091 RES 45K 6681A, 668 2A 0698- 3160 RES 31.
114 Repla ceable Part s Table 5- 14. A10 Cont rol Assembly, Rep laceable Parts (contin ued) Ref. Desig. Agilent Part No. Desc ription U506 5080-2 305 PRGMD- IC, SEC U507 1820-307 9 IC MC 74HC138N U510.
Diagrams 115 6 Diagrams Introduction This chapt er contai ns draw ings and diag rams for t roublesh ooting an d maintain ing Agilent Series 668xA Po w er Supplies. Unless otherwise specified, a drawing or diagram applies to all m odels of the series. W iring conn ections to external equipment are sh own in the Power Supply Operating Manual.
116 Diag rams Table 6- 2. Signal Name M nemonics Mnemonic Description Mnemonic Description A(0)--A(15) Addres s lines MSRQ Microprocessor se rvice request AD (O)--AD(7) Addres s bus NDAC Not data acce.
Diagrams 117 Table 6- 3. Test Point s TEST POINT No. & Loc. Signal Tested Measurement and Conditions A2 GPIB BOARD J106- 4 Prim ary/chassis g round C onnect m eter or scope comm o n h ere. Then make measure ments at test points throug h . U101- 1 + 5V primary bias + 5V + 0.
118 Diag rams Table 6-3. Test Points (continued) TEST POINT No. & Loc. Signal Tested Measurement and Conditions Bias Board (c ontinued) U308-1 PREF +2.5V U308-5 RESET* Held low for approxim ately 50 ms at power- on, then goes high. U311-7 FAN DETECT +3V D317 -25V +3V U311-2 FAN_PWN +0.
Diagrams 119 Table 6-3. Test Points (continued) TEST POINT No. & Loc. Signal Tested Measurement and Conditions A10 Cont rol Board (continued) U600-10 DIVIDER CLOCK (Sheet 3) See Figure 6-1 U601-6 .
120 Diag rams Figure 6-1. Test Poin t Waveforms f or Table 6-3.
Diagrams 121 Figure 6-2. Circuit Board Cabling Diagram.
122 Diag rams Figure 6-3. A1 Front Panel Board, Component and Test Point Location.
Figure 6-4. A1 Front Panel Board, Schematic Diagram.
Figure 6-5. LED Board, Component and Test Point Location Figure 6-6. LED Board, Schematic Diag ram.
Figure 6-7. A2 GPIB Board, Component Location.
2 3 4 1 6 5 7 8 Figure 6-8. A2 GPIB Board , Schematic Diagram.
Figure 6-9. A3 FET Board, Component and Test Point Location.
Figure 6-1 0. A3 FET Board , Schematic Diagram (sheet 1 of 2).
Figure 6-1 0. A3 FET Board , Schematic Diagram (sheet 2 of 2).
Figure 6-11. A4 AC Input Board, Component and Test Point Location 9 10 11 12.
Figure 6-12. A4 AC Input Board, Schematic Diagram.
Figure 6-13. A5 DC Rail Board, Component and T est Point Loc ation 13 14.
Figure 6-1 4. A5 DC Rail Bo ard, Schematic Diagram 13 14.
Figure 6-15. A6 Bias Board, Component and Test Point Location 15 16 17 18 19.
Figure 6-1 6. A6 Bias Board , Schematic Di agram (She et 1of 2) 19.
Figure 6-1 6. A6 Bias Board , Schematic Di agram (She et 2 of 2) 15 16 17 18.
Figure 6-1 7. Power M esh, Schemati c Diagram, M odels 6680 A , 6681 A Only.
Figure 6-1 8. Power M esh, Schemati c Diagram M odels 6682 A , 6683 A, 6684 A O nly.
Figure 6-19. A7 Snubber Board, Component Location Figure 6-20. A7 Snubber Board, Schematic Diagram.
Figure 6-21. A8 Fast Sense Board, Component Location Figure 6-2 2. A8 Fast Sense Board, Schematic Di agram.
Figure 6-23. A9 Down Programming/Slow Sense, Component Location.
Figure 6-24. A9 Down Programming/Slow Sense, Schematic Diagram.
Figur e 6-25. A 10 Contr o l Boa r d, Compone nt a nd T es t Po int Loc at ion 47 55 44 41 42 46 48 43 63 53 51 50 49 45 38 36 60 62 61 59 54 52 57 58 56 64 37 21 36 22 20 39 40.
Figure 6-2 6. A10 Control Board, Schemat ic Diagram ( Sheet 1 of 4) 21 22 20 36 37 38 63.
Figure 6-2 6. A10 Control Board, Schemat ic Diagram ( Sheet 2 of 4) 64 40 39.
Figure 6-2 6. A10 Control Board, Schemat ic Diagram ( Sheet 3 of 4) 56 61 60 58 57 59 54 52 53 50 51 49 62 55 65 66.
Figure 6-2 6. A10 Control Board, Schemat ic Diagram ( Sheet 4 of 4) 48 43 47 42 41 39 46 45 44 40.
Backdating 149 A Backdating Manual backdat ing descri bes changes that must be m ade to this m anual for pow er suppli es whose seri al numbers are l ower than those listed in the title page to this manual. Look in th e following table and locate your Agilent model.
150 Backd ating In Table 5-9 A5 DC Rail Board DELET E C418, 0. 022uF 250VA C "Y" rated P/N 01 60-4048 Fus e Clips , REF F420 & 421 1/4" P/N 21 10-0726, qt y , 4. ADD Fus e Holder, RE F F420 & 421, 5 x 30mm P/N 2110-0689, qty 2. CHANGE F420 & 421, from 0.
Backdating 151 Table A-1. A 2 GPIB Parts List Ref Desig. Agilent Part No. Description ELEC TRICAL PAR TS C102-105 0160-482 2 Capacitor 1000pF 5% C106 0180-0 155 Capacitor 2.2 µ F 20V C107,108 0160- 4787 Capacit or 22pF 5% 100V C109-111 ,114,115,121 0160-542 2 Capacitor 0.
152 Backd ating Tab le A -1. A 2 GPIB Parts List (continued) Ref Desig. Agilent Part No. Description ELEC TRICAL PAR TS TB101 0360-2 312 Terminal block (digi tal cont rol) U101 1826-046 8 IC MC3423PI .
Backdating 153 Figure A-1. A2 GPIB Component Parts List.
Index 155 Index A A1 Front Panel Board, tes t header .............................................................................................. ................................ 57 A2 GPIB Board, test header ........................................
156 Index CV source eff ect, defined...................................................................................................... ...................................... 17 CV source eff ect, testing ...........................................
Index 157 UART PARITY .................................................................................................................... ............................... 35 error mes sage, selftest ....................................................
158 Index Mnemonics signa l names ......................................................................................................... ................................. 140 mutual coupling, test lead ..............................................
Index 159 load ........................................................................................................................... ........................................... 12 resistor, cu rrent monitor ......................................
160 Index Troubles hooting test points .................................................................................................................... ....................................... 142 troubles hooting chart output h eld high ..........
An important point after buying a device Agilent Technologies 6681A (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Agilent Technologies 6681A yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Agilent Technologies 6681A - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Agilent Technologies 6681A you will learn all the available features of the product, as well as information on its operation. The information that you get Agilent Technologies 6681A will certainly help you make a decision on the purchase.
If you already are a holder of Agilent Technologies 6681A, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Agilent Technologies 6681A.
However, one of the most important roles played by the user manual is to help in solving problems with Agilent Technologies 6681A. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Agilent Technologies 6681A along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
