NAD-C272-cd-sm维修电路原理图.pdf

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1、NAD SERVICE MANUAL C 272 STEREO AMPLIFIER C 272 STEREO AMPLIFIER RadioFans.CN 收音机爱 好者资料库 SPECIFICATIONS STEREO MODE CONTINUOUS AVERAGE POWER = 150 W (21.8 dBW) OUTPUT INTO 8 OHMS OR 4 OHMS (Min. power per channel, 20 Hz 20 kHz, both channels driven, with no more than rated distortion) Rated Distorti

2、on = 0.03% (THD 20 Hz 20 kHz) Clipping power = 170 W (maximum continuous power per channel). IHF dynamic headroom at 8 ohms = +2.3 dB IHF dynamic power (Maximum short term power per channel) 8 ohms: = 230 W (23.6 dBW) 4 ohms: = 410 W (26.1 dBW) 2 ohms: = 520 W (27.2 dBW) Damping factor 150 (ref. 8 o

3、hms 50Hz) Input Impedance R = 20 kohms C = 470 pF Input sensitivity (for rated output into 8 ohms) 1.2 V0.1V Voltage gain 29 dB Frequency response 20 Hz 20 kHz 0.3 dB - 3 dB at 3 Hz/70 kHz Signal / Noise ratio, A-weighted 100 dB ref. 1 W 120 dB ref. rated power BRIDGED （MONOPHONIC）MODE CONTINUOUS AV

4、ERAGE POWER 330 W 25.2 dBW） OUTPUT INTO 8 OHMS (Min. power per channel, with no more than rated distortion) IHF dynamic headroom at 8 ohms 3 dB IHF dynamic power 8 ohms: 800 W (29.0 dBW) IHF dynamic power 4 ohms: 1200 W (30.8 dBW) DIMENSIONS AND WEIGHTS Net Weight 12.5 kg ( 27.5 Ib) Shipping Weight

5、14.2 kg ( 31.3 Ib) Dimension (W H D) 435 133 350 mm RadioFans.CN 收音机爱 好者资料库 ALIGNMENT PROCEDURE (C272) I. INITIAL ADJUSTMENT (No load connected) A. OUTPUT OFFSET VOLTAGE 1. Connect a DC Millivoltmeter to L Channel TP2 (DC) and TP8 (GND). 2. Turn unit “ON” and adjust VR301 (100ohms) to get a reading

6、of 0V+/-30mV. 3. Connect a DC Millivoltmeter to R Channel TP5 (DC) and TP7, then adjust VR401(100ohms) to get a reading of 0V+/-30mV reading on meter. B. IDLING CURRENT 1. Connect a DC Millivoltmeter to L Channel TP1 (IDL) and TP3 (IDL), then adjust VR302 (500 ohms) for 67.5mV reading on meter. 2. C

7、onnect a DC Millivoltmeter to R Channel TP4 (IDL) and TP6 (IDL), then adjust VR402 (500 ohms) for 67.5mV reading on meter. II. ISC ADJUSTMENT (WITH LOAD CONNECTED) 1. Connect a DC Millivoltmeter to Power Board CB725, and connect 4 ohms load to both L&R speaker output terminals. Then feed 20kHz signa

8、l to Fixed In RCA. 2. Turn unit ”ON” and try to get 15W on speaker output terminal. Then adjust VR701 (82kohms) to get a reading of 0V+/-10mV. 3. Change the load to 8 ohms and try to get 160W on speaker output terminals. Then adjust VR701 (82kohms) to get a reading of 1.4V+/-30mV. III. FINAL ADJUSTM

9、ENT Repeat procedure A and B for offset voltage and idling current alignment respectively. RadioFans.CN 收音机爱 好者资料库 RadioFans.CN 收音机爱 好者资料库 DRAFT C702 22n/250VC703 22n/250VC715 C716 Q703 C1815 Q702 A1015 TC701 TIC116D TC702 TIC116D R707 1K R713 22K R709 100 R7111K R712 1K R708 1K R710 100 R714 22K R7

10、16 0.025/3W 10% R717 100 MF 1% Q706 A1015 Q707 A1015 R718 9K1 MF 1% R719 220K ! ! ! ! RED GRY BLK ORG VIO ! ! ! ! H1 H2 L1 L2 52.1V AC 10% 10% 33.1V AC C704 22n/100V C705 22n/250V ! 10% 10% 32.5V AC C711 22n/250V C712 22n/250V R701 R702 R703 R704 C721 22n/100V C722 22n/100V C723 1000u/100V C724 1000

11、u/100V R721 1K R722 1K R723 33/FS R726 1K R725 1K R727 1K R730 1K R728 1K R735 3K3 1%MF R732 1K R731 1K8 R734 9K1 1%MF R724 33/FS R733 1K R737 22K 1%MF C728 100u/25V C732 10u/100V C733 4u7/100V C729 100u/25V C737 22u/100V C734 22n 100V C731 47P C730 47P C735 22n 100V Q708 KSC2690 Q710 C1775 Q711 C17

12、75 Q709 KSA1220 Q712 A872 D703 1N4148 D704 1N4148 D706 1N4148 D705 1N4148 C725 47u100V C726 47u/100V R736 22K 1%MF C736 22u/100V ! ! ! 60.5V AC T701: TI-65381: AC 230V AC S1 AC S2 + + - - B703 DB104 AC S1 AC S2 + + - - B704 DB104 AC S1 AC S2 + + - - B701 KBU1004 AC S1 AC S2 + + - - B702 KBU1004 C713

13、 22n/250V C714 22n/250V D702 1N5401 10A10A 0.5A0.5A Q704 A1015 Q705 C1815 R715 22K C717 C718 C719 N.I. C720 N.I. 1 2 3 4 7 8 9 5 6 10 11 12 T701 MAIN TRANSFORMER 1 2 3 4 5 CZ702 5PIN 1 2 3 4 5 CB702 5PIN 1 2 3 4 5 CZ701 5PIN 1 2 3 4 5 CB701 5PIN R720 100 R729 100 C727 0.1u FUSEABLE : 4 X 1/1W AC-DET

14、 ISC-C ISC-S 4X10000uF/80V +20%/-20% C715-C718 +18V R742 249 R743 249 R740 3K32 R741 3K32 C744 22u/50V C745 22u/50V C746 22n 100V C747 22n 100V IN IC702 LM317M IN IC703 LM337M C740 22n 100V C741 22n 100V +18V -18V C738 2200uF/50V C739 2200uF/50V C742 10u/50V C743 10u/50V D7071N4148 D7081N4148 1 2 CB

15、703 2PIN C706 0.1u ! AC S1 AC S2 + + - - B705 DB104 C708 1000u/16V C707 0.1u R706 10K 1 4 56 7 9 10 2 8 T702 STANDBY TRANSFORMER PJ701 +12V TRIG R705 2K2 Q701 C1815 1 2 3 SW702A AUTO TRIG 12 RL701A STAND-BY RL701B 5V D701 1N4148 IN IC7017805 C710 0.1u C709 10uF TGND 1 2 3 4 CZ706 4PIN 1 2 3 4 CZ706A

16、 4PIN 1 2 CZ703 2PIN F701 T4AL/250V(CE) R738 200/1W FS R739 200/1W FS R740-R743=1% MF YEL BLU WHI BLU YEL 1 2 CZ704 2PIN +T5V +T5V TGND R749 10K D710 1N4148 R758 100K 1% MF R759 91K 1% MF R757 62K 1% MF R756 390K 1% MF C753 10u/25V R754 1K C750 10u/25V R755 1K C751 10u/25V IC704A TL082CP C752 10u/25

17、V R751 1M IC704B TL082CP R745 27K MF R752 1M C748 1u/50V C749 1u/50V R750 10K D711 1N4148 R746 270K 1% MF D712 1N4148 R748 100K R753 100K 1% MF -18V D709 1N4148 -18V +18V ISC-S ISC-C R772 56K R773 56K C758 330u/16V C756 4u7/100V C757 220n/63V R764 10K R769 56K C755 47u/50V 1 2 3 4 5 6 7 8 IC705 uPC1

18、237HA +V34 R771 22K R770 22K D719 1N4148 D718 10V Q715 A1015 C754 10u/50V R762 22K R763 10K R765 10K R768 10K D713 1N4148 RL702B 36V R766 220/2W FP L-OUT R-OUT R767 5K6 +V34 PROTECT-I PT-OUT AC-DET +5V 1 2 CB707 2PIN 1 2 CB708 2PIN LA G1 G2 RA LB G3 G4 RB CB715 BINDING POSTS 12 RL702A RL-LCH 12 RL70

19、3A RL-RCH 1 2 3 4 5 6 7 8 CZ709A 8PIN 1 2 3 4 5 6 7 8 CZ710A 8PIN C759 22n 100V C760 22n 100V C761 2n2 C762 2n2 L-OUT R-OUT +64V -64V 1 2 3 SW704A BG-SIGNAL PROTECT-I 1 2 3 SW703A SOFTCLIP 10 11 12 SW704D BRIDGE 1 2 3 CZ711 3PIN +18V R779 10K R777 10K R774 4K7 D722 1N4148 D721 1N4148 D720 1N4148 R77

20、5 560 R778 4K7 R776 0 Q716 C1815 Q717 C1815 1 2 3 CZ712 3PIN +18V +18V PT-OUT 4 5 6 SW702B AUTO TRIG +5V Q714 C1815 Q713 C1815 R761 22K R760 22K PROTECT-T PROTECT-T ISC-C R783 25K R782 25K R785 1K R784 1K R781 1K R780 1K +68V -68V C764 10u/25V C763 10u/25V D71424V D71524V 4 5 6 SW703B SOFTCLIP +64V

21、-64V +18V +68V -68V R744 100 Q718 C1815 R786 22K D716 1N4148 +18V -18V C270 STANDBY BOARD LOUT GND +64V -64V -64V +64V GND ROUT MUTE-L MUTE-R POS90 POS90 POS80 POS80 SC-P SC-P SC-N SC-N OVERI-S OVERI-S -68V -68V +68V +68V BG-O BG-S1 2 CZ714A 2PIN BG-G 4 5 6 SW704B BG-GND 1 2 CZ713A 2PIN LIN GND 1 2

22、3 4 5 6 7 8 9 CZ61 9PIN R612 1K C62 100P R62 220 MF R64 2.2M MF Q62 2SK369 R68 1K MF R610 100/MF Q65 2SA970A Q68 2SD667A Q66 2SB647A D63 1N4148 D64 1N4148 C64 39P R62010/MF C68 0.1u C67 0.1u MGND 1 2 3 4 5 6 7 8 9 CB61 9PIN MLO +18V LOUT LIN- LIN+ GND RIN+ RIN- ROUT -18V R618 47/MF R616 0 R614 10K M

23、GND +18M -18MMGND MLOMRO R621 N.I. C611 N.I. MR-FB C270-INPUT BUFFER R66 N.I. 1% MF C610 47P R611 1K C61 100P R61 220 MF R63 2.2M MF Q61 2SK369 R67 1K MF R69 100/MF Q63 2SA970A Q67 2SD667A Q64 2SB647A D61 1N4148 D62 1N4148 C63 39P R619 10/MF C66 0.1u C65 0.1u MGND MRO R617 47/MF R615 0 R613 10K MGND

24、 +18M R65 N.I. 1% MF C69 47P MR-FB -18M ML-FB ML-FB -18M RIN GND2SA1943 BCE 2SA1943 2SA872 2SA1015 2SC1815 A872 E C B B649 TL431 LM317: R A K E C B TL431 2SB649 2SD669 3:IN LM337: 1:ADJUST,2:IN, 1 2 3 LM7805 LM7805 1:IN 2:GND,3:OUT 2SC5200 R101 220 MF C101 100P R102 2M2 RCA1A FIXED-L R201 220 MF C20

25、1 100P R202 2M2 RCA1B FIXED-R 1 2 3 SW705A F/V SW 4 5 6 SW705B F/V SW R103 220 MF C102 100P R104 2M2 RCA2A VARI-L R203 220 MF C202 100P R204 2M2 RCA2B VARI-R A1 RV1A 1K A2 RV1B 1K R105 0 R205 0 C10310n 63V C20310n 63V C104100uF C204100uF 1 2 3 CZ301A 3PIN 1 2 3 CZ401A 3PIN +18V-18VC105 10uF C205 10u

26、F 7 8 9 SW705C F/V SW 10 11 12 SW705D F/V SW BUF-R BUF-R 1 2 3 LM317 LM337 1:ADJUST,2:OUT, 3:OUT 2.5Vref + - Reference(R) Cathode (K) Anode (A) 1 2 3 KSC2690 TL431 B647 E C B 2SB647A 2SD667A C6130.22u C6120.22u C765 22u/50V R5 0 R6 0C5 N.I. C6 N.I. P15 LOUT P16 SGND P7-64V P9PGND P11 +64V P13 LOUT +

27、64V -64V P17 ROUT P18 SGND P8-64V P10 PGND P12 +64V P14 ROUT C766 4n7/400V GND K A G TIC116D TIC116D 2SA970 GND GND C767 10u/25V D723 1N4148 R788 100K 1% MF R-OUT L-OUT D724 1N4148 R789 270K 1% MF RL703B 36V R7902K2 +18V ! R791 100K R792 2K R793 560 C407 22P/500V C402 220P C405 22P/500V C415 0.1u R4

28、02 22K R403 100 MF R412 100 R404 100 R413 39K R405 39K R414 100 R406 100 Q413 2SB649A Q410 2SB649A Q409 2SA1015 Q405 2SA1015 Q407 2SA872 Q406 2SA872 Q401 2SA872 Q411 2SD669A Q412 2SC1815 Q408 2SC1815 Q404 2SC1775 Q403 2SC1775 Q402 2SC1775 R408 33 R420 33 R418 47K 1%MF R459 10/1W FS R4603R3/1W FP R41

29、5 1K R423 100 MF 1% R421 1K MF 1% R417 150 1% R419 10K 0.5W 1%MF R427 39K R407 910 MF 1% R416 10K R428 100 MF R411 1K R410 10K R426 100K R424 100K R409 100 MF 1% D403 1N4148 D404 1N4148 D406 1N4148 D405 1N4148 C408 100P Q414 2SD669A R430 3R3 1W FP R432 510 1W FP R434 2K2 3W FP R438 3R3 1W FP R441 51

30、0 1W FP R444 2K2 3W FP R437 100 1W FS R429 100 1W FS R431 4R7 FS R439 4R7 FS R43633 R44033 L401 10uH L402 10uH R445 1K2 R446 820 Q415 KSC2690 Q417 2SC4937 Q422 2SC5200 Q420 2SC5200 Q418 2SA1837 R450 0.2 1W FS R452 0.2 1W FS R451 0.2 1W FS R453 0.2 1W FS R457 0.05 5W R456 0.05 5W R448 75 1W FP R449 7

31、5 1W FP R44210K R43310K C413 470P 500V C414 470P 500V Q419 2SA1943 Q421 2SA1943 D408 BAV21 D407 BAV21 C418 0.1u 100V L403 1uH R401 470/MF R-FDBK C401 10uF C403 10uF/25V C404 10uF/25V C406 2200u/6.3V C411 100uF C412 100u/25V R435 10K R44310K C416 0.1u 100V C417 0.1u 100VC409 0.1u 100V C410 0.1u 100V

32、Q426 2SA1015 Q425 C1815 R464 6K8 C421 10u 50V R463 22K R461 1K R462 15K C420 22n 100V D409 1N4148 R465 22K R454 0.2 1W FS Q423 2SA1943 Q424 2SC5200 R455 0.2 1W FS R422 9K1 0.5W 1%MF 1 2 CZ401 2PIN 1 VR401 180 R466 t=90 C R467 t=80 C RSCN R-FDBK D402 18V D401 18V IC402 TL431 IC401 TL431 1 VR402 500 R

33、447 220 Q416 A1015 TP4 IDLING-I TP5 OFFSET TP6 IDLING-I R468 0.2 1W FS Q427 2SA1943 Q428 2SC5200 R469 0.2 1W FS -V64R +V64R 1 2 CZ708 2PIN 1 2 3 4 5 6 7 8 CZ710 8PIN -64V +64V GND ROUT MUTE-R POS90 POS80 SC-P SC-N OVERI-S -68V +68V GND BG-S RSCN RSCP R-MU Q429 2SC1775 Q430 2SA872 -V68R +V68R R425 10

34、0 R470 100 RSCP +V68R -V68R +V64R -V64R R471 2K2 R-MU R4728K2 R358 100/0.5W MF 1 2 3 CZ714 3PIN BG-GBG-G BG-S BG-S BG-G C307 22P/500V C302 220P C305 22P/500V C315 0.1u R302 22K R303 100 MF R312 100 R304 100 R313 39K R305 39K R314 100 R306 100 Q313 2SB649A Q310 2SB649A Q309 2SA1015 Q305 2SA1015 Q307

35、2SA872 Q306 2SA872 Q301 2SA872 Q311 2SD669A Q312 2SC1815 Q308 2SC1815 Q304 2SC1775 Q303 2SC1775 Q302 2SC1775 R308 33 R320 33 R318 47K 1%MF R359 10/1W FS R360 3R3/1W FP R315 1K R323 100 MF 1% R321 1K MF 1% R317 150 1% R319 10K 0.5W 1%MF R327 39K R307 910 MF 1% R316 10K R328 100 MF R311 1K R310 10K R3

36、26 100K R324 100K R309 100 MF 1% D303 1N4148 D304 1N4148 D306 1N4148 D305 1N4148 C308 100P Q314 2SD669A R330 3R3 1W FP R332 510 1W FP R334 2K2 3W FP R338 3R3 1W FP R341 510 1W FP R344 2K2 3W FP R337 100 1W FS R329100 1W FS R331 4R7/FS R339 4R7/FS R33633 R34033 L301 10uH L302 10uH R345 1K2 R346 820 Q

37、315 KSC2690 Q317 2SC4793 Q322 2SC5200 Q320 2SC5200 Q318 2SA1837 R350 0.2 1W FS R352 0.2 1W FS R351 0.2 1W FS R353 0.2 1W FS R357 0.05 5W R356 0.05 5W R348 75 1W FP R349 75 1W FP R34210K R33310K C313 470P 500V C314 470P 500V Q319 2SA1943 Q321 2SA1943 D308 BAV21 D307 BAV21 C318 0.1u 100V L303 1uH R301

38、 470/MF L-FDBK C301 10uF C303 10UF/25V C304 10uF/25V C306 2200u/6.3V C311 100uF C312 100u/25V R335 10K R34310K C316 0.1u 100V C317 0.1u 100VC309 0.1u 100V C310 0.1u 100V Q326 2SA1015 Q325 C1815 R364 6K8 C321 10u 50V R363 22K R361 1K R362 15K C320 22n 100V D309 1N4148 R365 22K R354 0.2 1W FS Q323 2SA

39、1943 Q324 2SC5200 R355 0.2 1W FS R4588K2 R322 9K1 0.5W 1%MF 1 2 CZ301 2PIN 1 VR301 180 R366 t=90 C R367 t=80 C LSCN L-FDBK D302 18V D301 18V IC302 TL431 IC301 TL431 1 VR302 500 R347 220 Q316 A1015 TP1 IDLING-I TP2 OFFSET TP3 IDLING-I R368 0.2 1W FS Q327 2SA1943 Q328 2SC5200 R369 0.2 1W FS -V64L +V64

40、L 1 2 CZ707 2PIN 1 2 3 4 5 6 7 8 CZ709 8PIN -64V +64V LOUT MUTE-L POS90 POS80 SC-P SC-N OVERI-S -68V +68V BG-O LSCN LSCP L-MU Q329 2SC1775 Q330 2SA872 -V68L +V68L R325100 R370100 LSCP +V68L -V68L +V64L -V64L R3712K2 L-MU 1 2 CZ713 2PIN GND GND C322 10u/100V C319 10u/100V C422 10u/100V C419 10u/100V

41、TP8 GND TP7 GND C323 0.1u 100V C423 0.1u 100V Q431 C2878 1% 1% R797 10K B- B- 1 2 CB716 M-TEST 1 2 CB717 M+TEST 1 VR701 82K R-OUT L-OUT 1 2 CZ718 2PIN 1 2 CZ719 2PIN 1 2 CB719 2PIN 1 2 CB718 2PIN 1 2 3 CB720 68VTEST +68V -68V 1 2 3 CB723 18VTEST +18V -18V T6.3AL/250V(AH) 1 2 3 CB724 N/A TGND 1 2 CB7

42、25 PTEST 7 8 9 SW704C BRIDGE 1 2 CZ705 2PIN GND ROUT 1 2 CB705 2PIN R747 470K -18V NOTE: 1. RESISTORS ARE CARBON FILM 1/4W 5% UNLESS SPECIFIED. FP - FLAME PROOF 5%. FS-FUSIBLE 5% MF - METAL FILM 5%. CE-CERAMIC CASE 5% 2. ALL CAPACITORS, UNLESS OTHERWISE SPECIFIED, ARE 50V, 20% 3. COMPONENTS WITH N.I

43、. MEANS NOT INSERT. 4. COMPONENTS WITH * ARE ADJUSTABLE PARTS. 5. COMPONENTS WITH ARE SAFETY CRITICAL PARTS. ! 1 2 3 4 5 CZ705 230V 120V C272 NAD ELECTRONICS INTERNATIONAL Document Sheet: Date: Date: Date: DraftedPL CheckedApproved by:by:by: Number: REV.DateECN No.DESCRIPTIONAPPRO. Project:State: PT

44、A Checked by: Date: HS4_C272_B007 V3.0-MAIN.sch TRIG OFF R799 2.2K CHANGE R744 TO 100 ADD R799 1/4W 2K RadioFans.CN 收音机爱 好者资料库 DRAFT CIN 11 COUT 9 COUT 10 RST 12 Q4 7 Q5 5 Q6 4 Q7 6 Q8 14 Q9 13 Q10 15 Q12 1 Q13 2 Q14 3 VCC 16 GND 8 U801 CD4060 CLK 11 D 12 SD 10 CD 13 Q 9 Q 8 U803B 74HC74 CLK 3 D 2 S

45、D 4 CD 1 Q 5 Q 6 714 U803A 74HC74 89 U802D 74HC14 1011 U802E 74HC14 12 714 U802A 74HC14 34 U802B 74HC14 56 U802C 74HC14 1213 U802F 74HC14 R802 10K Q801 2SC1815 R803 10K R804 10K R810 100K R814 200K R801 2M R805 10K R806 10K R807 10K R813 1M R811 100K R808 10K R809 10K R816 10K R815 10K R817 10K R819

46、 10K R818 10K Q802 2SC1815 Q803 2SC1815 C803 0.1uF C807 2.2uF C806 0.1uF D801 1N4148 R812 1M C802 0.1uF +5V +5V +5V +5V +5V +5V C801 0.1uF C805 0.1uF C804 0.1uF 1 2 3 4 5 6 CZ804 6PIN 1 2 3 CZ801 3PIN +5V 1 2 3 4 CZ802 4PIN 1 2 3 4 CZ803 4PIN +5V OUTPUT IN SENSE TRIG IN 3 12 Q804 2SA1015 HS4_C272_B0

47、07 V4.0-ATO.SCH C272 R901 1M R902 1M R910 10K R907 30M R909 10K R911 1M C906 10pF C904 100nF C909 0.1uF 12 D903 1N4148 12 D904 1N4148 12 D905 1N4148 12 D906 1N4148 12D901 1N4148 12D907 1N4148 12 D911 1N4148 +5V +5V +5V C901 100nF C903 100nF C905 100nF C902 100nF R908 30M C907 10pF 12 D908 1N4148 12

48、D909 1N4148 12 D910 1N4148 12 D912 1N4148 12D902 1N4148 12D913 1N4148 R906 100K R903 100K R905 100K R904 100K 3 2 1 84 U901A LF353 5 6 7 U901B LF353 12 C908 100nF 1 2 3 CZ901 3PIN 1 2 3 CZ902 3PIN S_LCH S_RCH 1 2 3 CZ903 3PIN 1 3 4 2 5 6 S901 Q901 2SC1815GR R913 100k R912 100k +5V 12 C910 100n 1 2 3

49、 3PIN 1 2 3 3PIN 1 2 3 4 5 6 6PIN R1101 0 R1102 47 LED1106 LED1105 R1105 1K R1104 1K SC BG +18V AGND LED1104LED1103LED1102 Q1103 2SA1015 Q1102 2SA1015 Q1101 2SA1015 R1103 510 TS1101 GND +5V TS LED_SENSE LED_TRIG LED_TS GREEN GREENGREENGREEN AMBER GREEN/AMBER/RED INSENSE BORAD ATO BORAD TACT SWITCH&LED BORAD LED1101 PWR TO MAIN BOARD CZ712 TO MAIN BOA