Philips-MC-77-Service-Manual(1) 电路图 维修手册.pdf

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1、Technical specification . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 Measurement setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 Warnings it is a dual-frequency oscillator with ceramic resonators 5300 and 5302, which resonate at 500kHz and 425kHz respectively. The re

2、sonators are switched by transistors 7309 and 7316, controlled by the OZ_SW line from the port expander 7406. The reason for 2 frequencies is to avoid tuner disturbances in the AM-band. The oscillator signal is shaped to square wave with 7312-B, afterwards buffered and fed to the amplifier modulator

3、s (ROZ to the right channel, LOZ to the left). One channel gets inverted clock to balance supply loading. Modulator The modulator forms the pulse width modulated signal. For each channel a seperate modulation is required. Power FETs The FETs require drivers which supply the gates. One for the high-s

4、ide-FET and one for the low-side-FET. Because of the different supply voltages also an additional level shifter is necessary per driver. Output filter The output filter is necessary to block the 500kHz square wave signal from the speaker. It consists of a series-mode coil 5101 and a capacity of appr

5、ox. 500nF (2116, 2134), which forms a Chebycheff filter with 40kHz cut-off frequency at 6 load. For EMC reasons both, the speaker output and the return ground are fed through a common mode coil 5102, the filter is further improved by splitting the output capacity into 2116 before and 2134 after the

6、common mode coil. All above mentioned circuitries are located inside the metal shielding box. LF Analog Audio Signal Modulated Digital Audio Signal +VL -VL +VL 0 0 -VL t Duty cycle 9:1 (DC value nearly +VL) Amplitude pos. max. Duty cycle 1:1 (DC value is zero) Amplitude zero Duty cycle 1:9 (DC value

7、 nearly -VL) Amplitude neg. max. 11-2 Class-D Circuit Description (BASED ONPOWER2002 MODULE- 70W CLASSD) V1L+6V+AMPV1L+6V V1L -32V +5V -38V -32V -38V -AMP-38V OFF ON OFFON Analog Pre-amp. Modulator Driver Power-amp. Level shifter Level shifter Square wave Oscillator analog audio signal f= 20Hz .20kH

8、z amplified analog audio signal f= 20Hz .20kHz square wave 500kHz duty cycle 1:1 square wave 500kHz variable duty cycle 0V 5V 0V 5V square wave 500kHz variable duty cycle -30V +38V square wave 500kHz variable duty cycle -38V +38V square wave 500kHz variable duty cycle -38V -32V output filter Blockdi

9、agram Class D 2002 04 05 Blockdiagram Class D Functional Description: Refers to the left channel in schematic diagrams. The first stage of the modulator is an error integrator which compares the input to the (20 dB amplified) output signal of the power stage. The difference is leading to a current,

10、which loads the integrator 7122-A. The second stage (7122-B) is again integrating, thus creating high gain at low frequency, which leads to high feedback and low distortion. The next stage is a comparator, which compares the integrated voltage to a triangle wave - thus creating a voltage controlled

11、duty cycle. The comparator is realized by cascaded gates. At pin 12 of IC7122 there is a square wave with the same frequency and duty cycle as the desired output. The next task is to feed this information to the output FETs. Both FETs are n-channel types, so they are modulated by feeding the gate in

12、 respect to the source connection. We use inverters 74LV14 as drivers. The driver for the low-side FET (7121) is supplied by the negative supply -VL and a voltage +VL generated by 7115, which is 6.3V higher than -VL. The digital signal is level-shifted by 7128 to the negative supply reference. 3142,

13、 6111 and 2126 together is a delay circuit for rising edges by approx. 50ns, this is to compensate the switch-off delay of the FETs and ensures that both FETs are not conducting at the same time. The high-side FET (7109) is controlled by the inverted signal taken from pin 2 of 7118-A, which is level

14、-shifted by transistor 7119. The driver for the high-side FET is supplied by a floating voltage between the amplifier output -V1L and +V1L, created by the charge pump 6107, 2114 regulated by 7114 to a 6.3V higher level. The pump is supplied by +5.6V to ensure supply at start-up (no signal). The nece

15、ssary delay for the rising edge is generated by the level-shifter (mainly the pull-up 3117) and the input capacity of the driver (pin 13 of 7105-F). The last stage in the gate driver consists of three gates in parallel for increased output current for the capacitive load, afterwards comes a 22R seri

16、es resistor for soft rising edges and a transistor for very fast falling edges. This combination gives the best compromise of efficiency and radiation. Protection Circuits: The amplifier is protected against low load impedance (including short circuit). Current is sensed by shunts 3101, 3130 in both

17、 supplies. Overcurrent at the positive supply is then sensed by 7104, the negative supply overcurrent triggers 7117, which then also triggers 7104. The collector current then triggers the monoflop 7122-D and -E, giving a high pulse at pin 8. This shuts off level-shifter 7128 and triggers transistor

18、7129, which draws current into the emitter resistors (3134, 3127) of level-shifter 7119, which is therefore also shut off. So both FETs are shut off for approx. 0.2 sec, afterwards the amplifier tries to work again, but if the overload continues the on-time is only a few cycles. The shut-off mechani

19、sm is also used to shut off the amplifier during headphone usage; this is done by pulling pin 11 of 7122-E high. The line AMP_OFF is controlled by the port expander 7406. The loudspeakers are protected against DC voltages resulting e.g. from defective FETs, voltages greater than +- 2V are detected b

20、y 7110+7112 and pull down the DC_PROT line, which disables the speaker relay 1201. The gain of the class-D amplifier is 20dB, adjusted by the feedback resistors 3136, 3149 and the input resistors 3139, 3340. The input reference voltage for 7122-A is approx. half the supply, therefore 3144, 3148 are

21、used for offset compensation. This compensation can be fine-tuned by the potentiometer 3306 to reach 425kHz OZ_SW = L - 500kHz 11.5V 5.2V 5.2V 4.1V 0V 5V OSCILLATOR PRE - AMPLIFIER A A 3 for wave forms see chapter 11-4 Service Hints Attention: Adjustment to 0V 1mV has to be done with cold set. After

22、 operating a few minutes the value may increase up to 30mV. 11-1111-11 2106 B112134 E13 2132 C4 2130 G10 2128 G10 2126 F7 2125 E1 2124 F10 2122 C10 E 2118 F10 2117 E13 2116 E12 2115 E13 2114 D9 2112 D10 2111 C3 2110 D8 2109 C13 2104 A2 2103 A9 2102 A10 2101 A11 2100 A10 3110 B53135 E9 3134 D6 3133 D

23、7 3130 F10 3129 F10 3128 E13 3127 C2 3126 A1 2136 F10 2135 F3 3122 C4 3121 C3 3120 C3 3119 D9 3117 B6 3116 C12 3115 E5 3114 B5 3113 C13 2120 E1 2119 F23109 B9 3108 A2 3107 D7 3106 B11 3103 B10 3102 C2 3101 B10 3100 A2 2137 G12 2108 A5 5100 A107111 C9 7110 C13 7109 B10 7105-F B6 7105-E B7 7105-D B8 7

24、105-C B8 7105-B C8 3139 E2 3136 E11 6111 F7 6109 E6 6108 D4 6107 D9 6106 D8 6104 C12 5105 A2 5103 G10 5102 D12 3125 F3 3123 D93149 G2 3148 F2 3147 B1 3146 F5 3144 F2 3143 E5 3142 F7 3141 C10 3140 E3 3112 C13 7119 D77113 F9 7112 C12 7130 A3 7129 B2 7128 E5 7122-F E4 7122-E A5 7122-D A4 7122-C E3 7122

25、-B E3 7122-A E2 7105-A C8 7104 B117118-F F8 7118-E F8 7118-D E8 7118-C F7 7118-B F6 7118-A F5 7117 F11 7115 C4 7114 C8 5101 D12 876 8 4321 3121110 7105 = 74LV14 7118 = 74LV14 BC856B BC856B STP14NF12FP STP14NF12FP 2SC2713-GR 8300 G13 7131 C27121 E10 4 BC856B 7122 = 74HCU04D 7122 = 74HCU04D BC807-25 B

26、C817-25 BC817-25 BC807-25 2SC2713-GR 21 G F B D C B A 10 G F E D C 5 A 131211 13 9 9765 12 7122-F 1312 7118-A 7122-E 11 7 10 6 7122-D 9 7 8 7 14 2 7122-C 5 1110 7122-A 1 7118-D 9 14 8 7105-E 7118-F 13 7 12 7118-E 1110 8 7118-C 56 7105-D 9 14 3139 1n5 2119 2 7105-C 56 1K 4 7105-A 1 7 BAS316 7105-B 3

27、3119 3K9 6107 10u 2114 2110 BZX384-C6V8 6106 22R 3109 1u 3117 2K2 7114 3142 1K 47p 2126 1u 2120 1K5 3140 22R 3141 1K 3146 100n 220p 2122 2128 2124 10K 3136 4 22R 3135 330u 1312 7118-B 3 5103 7105-F 3149 4K7 18K 3144 180K 3134 470R 3148 820R 3133 7115 7119 3122 3K9 100K 3110 7113 7121 7109 100n 10K 3

28、100 21015100 3120 3K9 3121 2111 10u 6108 3K9 BZX384-C6V8 5102 HF2024 12 43 2116 330u 2102 330n 1n 2115 3128 10K 3116 470K 7110 BC847BW 3112 47K 3113 22K 3143 470R 7128 47u 2109 BC857BW 7112 7104 BAS316 6104 3130 0R068 3103 470R 2n2 2106 7129 3101 0R068 10n 2108 3147 3K3 1n 2117 3106 22K 3129 470R 71

29、17 2n2 2118 10n 2104 4n7 2125 4 1 2 6111 BAS316 5101 30uH 220R 3123 3108 4K7 2134 220n 220p 2112 4 2135 1n 7122-B 3 7111 2132 1u 3115 470R 3107 1K 3114 4K7 100n 2130 100n 2100 8300 2136 100n 2137 100n 1K 3125 10K 3126 4K7 3102 100n 2103 6109 BC847BW 7130 1K 3127 BAS316 -AMP_L +VL +V1L +5V_AMP -V1L B

30、C846B 7131 SC_L -VL DC_PROT -VL +AMP_L -V1L +V1L AMP_OFF LOZ +V1L +VL -VL -VL SC_L AMP_D -VL 5V6-VR1 LNF +5V6_AMP to_LS_L AMPLIFIER PART LEFT CHANNEL -VL -VL Power2002 Class D Combi-Amplifier Part left channel 2002 04 25 D ABCF E 2 5 4 3 3 +5V_AMP 3 3 1 3 5 4 4 5 5 to_LS_L_neg Bead 100MHz Bead 100MH

31、z 0.7V 0V 0V 5V 5V 0.5V 0V -37.5V -38V -38V -19V -31.7V -38V -31V 2.3V 2.3V 2.0V 2.3V 2.2V 0.3V 0V -34.3V 3.0V -36.7V -36.8V 6.3V 5.9V 35.8V 0V 0V -38V -34.8V POWER STAGE DRIVER AMP ON = H = 4V MODULATOR 0V 0V AMP OFF = L = 0V 6.3V 38V 0V2.5V0.7V 0V 6.3V = supply for 7118 6.3V = supply for 7105 0VDC

32、 -38V B CFED G1 H1 H2 G2 I KJ 4 for wave forms see chapter 11-4 Service Hints 11-1211-12 7211 B13 7218 C10 7220 C13 7221 C9 7222 D8 7223 C4 7227 F11 7228 E7 BC807-25 BC856B 1314 A B C D E F G H A 7209-C B8 7209-D B7 7209-E B6 7209-F A8 7210 F9 2210 D8 7232 = 74HCU04D BC856B LS_L STP14NF12FP 2SC2713-

33、GR STP14NF12FP 1234567 7231 E10 7232-A F2 7232-B F3 7232-C F4 7232-D B3 7232-E B4 7232-F F4 7235-A G5 7235-B G6 7235-C F7 7235-D E8 7235-E F8 7235-F F8 7238 C2 7239 B2 7240 F5 7243 G14 12 7232 = 74HCU04D 7235 = 74LV14 BC856B 2211 D3 2212 D10 2213 G10 2214 E9 2215 E13 2216 E12 2217 D10 2218 G9 2219 E

34、13 2220 G10 B C D E F G H 1201 F14 1307-A E14 1307-B F14 2200 A10 2201 B10 2202 A11 2203 B9 2205 B14 2206 B10 2208 A5 2209 D123216 C11 BC817-25 BC807-25 BC817-25 7209 = 74LV14 3217 B5 3218 B3 3219 C13 3221 C2 3223 C13 3224 D12 3225 B6 3226 D12 3227 B2 891011121314 1234567891011 3258 G2 2SC2713-GR 32

35、59 G2 3261 E7 3262 G14 3263 G13 5200 A11 5201 E12 5202 E12 5203 G10 5205 D11 6202 B13 6204 D13 6205 D14 2221 F2 2222 E1 2225 G9 2226 F2 2227 G7 2229 H10 2234 E13 2236 D5 2237 F3 3201 B14 3203 B14 3205 B10 3207 B13 3209 B10 3210 A5 3211 F6 3213 G3 3215 C9 6211 D9 6212 D8 6213 D4 6214 E7 6216 F14 6217

36、 F7 7203 B13 7208 B11 7209-A C8 7209-B B8 3228 D9 3229 D13 3230 D3 3232 D4 3238 E13 3239 D10 3241 F10 3243 G10 3245 E7 3246 E6 3247 E9 3248 E11 3251 F2 3252 F3 3253 F7 3254 G2 3255 F5 3256 G5 6206 D13 6207 D14 6209 D12 3216 22K 47p 2227 14 2 470R 3246 7232-A 1 7 13 12 BAS316 6205 7232-F BC817-40 724

37、3 4 BAS316 6207 1K 3251 7235-B 3 BC847BW 7203 820R 3245 7238 BC846B 3218 4K7 3210 8 100n 2203 4K7 7209-D 9 3238 10K BC857BW 7220 180K 3254 1n 2215 1K 3213 7210 2K2 3225 7 10 330n 2216 7235-E 11 3241 470R 220p 2217 7232-C 56 3219 18K BAS316 2n2 2220 47n 2209 6217 3262 100R 6206 BAS316 7232-E 1110 520

38、1 30uH 41 2 2229 100n 7227 1307-B 3 4 13 7 12 7223 3205 0R068 7235-F 3K9 3228 7209-E 1110 3226 68K 2201 330u 98 5200 1K 3253 7232-D 2234220n 47K 3201 7211 BC857BW 2236 1u 2205 47u BAS316 1307-A 2 1 3221 1K 6214 12 3223 330K 7235-A 5203 7222 18K 3258 0R068 100K 3217 56 3243 12 7235-C 2226 4n7 7209-A

39、2 5 3 4 16 2237 1n 1201 OSA-SS 100n 2202 7208 2222 1u 7232-B 34 100n 2218 6202 BAS316 1 2 4 3 7228 7240 5202 HF2024 10u 2214 1K5 3252 4K7 3259 6209 BZX384-C4V7 7209-C 5 14 6 470K 3207 1n 2219 3209 470R 4u7 5205 7218 3261 7239 9 14 8 470R 100n 2213 7235-D 22n 2208 7221 22R 3239 4 6216 1N4148 7209-B 3

40、 6204 BAS316 BZX384-C6V8 6213 7231 2n2 2206 1u 2210 3230 2K2 3224 6K8 10K 3248 2212 220p 3247 22R 3K3 3227 6212 BZX384-C6V8 1K 3211 3263 10K 2211 10u 100n 2200 3255 470R 22R 3215 3229 10K 3232 1n5 2221 3K9 2225 330u 22K 3203 3256 1K BAS316 6211 RNF AMP_RELAIS 5V6-VR1 -VR FAN_CONT -VR SC_R -VR-VR -VR

41、 +AMP +V1R +V1R -V1R -AMP DC_PROT DC_PROT AMP_CLIP +AMP +5V_AMP -VR +12V_A LS_L AMP_D +VR SC_R ROZ -VR +VR +V1R 7 -V1R DE ABCF AMPLIFIER PART RIGHT CHANNEL Power2002 Class D Combi-Amplifier Part right channel 2002 04 25 4 3 3 3 1 2 5 3 4 LS_L_neg 4 4 2 1 1 5 5 5 Bead 100MHz Bead 100MHz MODULATOR DRI

42、VER POWER STAGE 0V -37.5V -38V -38V -19V -31.7V 6.3V = supply for 7235 -38V -38V -31V 2.3V 2.0V2.3V 2.3V 2.3V 0.3V 0V -34.3V 0V -38V -34.8V 0V0VDC 38V 0V 2.5V 3.0V 6.3V 0V 0.7V 3.0V -36.7V 0V -36.8V 6.3V 35.8V 5.9V 0.7V 0V 0V 5V 0.5V 5V 6.3V = supply for 7209 B CFED G1 H1 H2 G2 I KJ 5 for wave forms

43、 see chapter 11-4 Service Hints 11-1311-13 This assembly drawing shows a summary of all possible versions. For components used in a specific version see schematic diagram respectively partslist. Combi Board copperside view Power2002 70W Class D - Combi Board stage.7 2002 04 22 2100 G1 2101 G1 2103 G

44、2 2104 D6 2106 F2 2108 E3 2110 F1 2112 G2 2115 G4 2117 G4 2118 G2 2119 E2 2120 E2 2122 G2 2125 D2 2126 F3 2128 H3 2130 H3 2132 F4 2135 E2 2136 G3 2200 H5 2202 H5 2203 G6 2206 F7 2208 E6 2209 G9 2210 F5 2212 G6 2213 G7 2215 G4 2217 G6 2218 G7 2219 G4 2220 G7 2221 E5 2222 E6 2226 D5 2227 F7 2229 G8 22

45、36 F7 2237 E5 2300 E4 2301 E4 2303 F4 2305 F3 2306 E5 2307 E2 2308 D2 2312 F9 2313 D5 2314 E4 2316 F9 2318 C3 2319 D5 2320 E9 2322 E10 2325 D4 2326 D3 2327 D4 2332 C3 2333 C2 2334 E4 2335 D2 2336 D4 2400 D1 2401 D1 2404 C1 2407 C2 2409 D2 2411 D2 2413 D11 2414 D10 2415 D9 2417 B5 2418 E1 2419 D1 242

46、0 B5 2421 A6 2519 D11 2520 C11 2527 B11 2529 B10 2531 C11 2532 B11 2533 A11 2536 B3 2538 A10 2539 A10 2542 B8 2543 B8 2546 B9 2550 B9 2551 B8 2552 B8 2558 B7 2560 C8 2561 C8 2562 B8 2563 C8 2564 B7 2565 C7 2566 C7 2567 C7 2569 B7 2570 B8 2571 A7 2572 B7 2574 B7 2576 B7 2577 B7 2578 B7 2582 B1 3101 G

47、1 3102 F3 3103 F2 3106 F2 3107 F3 3108 E6 3109 G1 3110 E3 3112 H8 3113 G8 3114 E3 3115 E3 3116 G9 3117 F2 3119 F1 3120 G4 3121 G4 3122 F4 3125 E3 3126 B5 3127 F3 3128 G4 3129 G2 3130 G3 3133 F3 3134 F3 3135 H3 3136 F2 3140 E2 3142 F3 3143 E3 3144 E2 3146 F3 3147 F2 3148 E2 3149 E2 3201 H9 3203 H9 32

48、05 G5 3207 H10 3209 G7 3210 E6 3211 E6 3213 E5 3215 G5 3216 G7 3217 F6 3218 F6 3219 H9 3221 F6 3223 H9 3224 G9 3225 F5 3226 G9 3227 F6 3228 F5 3229 H9 3232 F7 3238 G4 3241 G7 3243 G7 3245 F6 3246 F6 3247 G7 3248 F5 3252 E5 3253 F6 3254 E5 3255 F6 3256 F7 3258 E5 3259 E5 3261 F6 3262 F10 3263 F11 330

49、2 F4 3303 F3 3311 E5 3312 F4 3313 F10 3314 F10 3316 C3 3318 F4 3319 D4 3320 E4 3321 G10 3322 F10 3323 G10 3324 E4 3325 D2 3326 D4 3328 D3 3330 D2 3331 D4 3332 C3 3334 C5 3336 D3 3337 D4 3338 C4 3339 C4 3340 D3 3341 F4 3342 E10 3343 E10 3344 F10 3345 F10 3346 F10 3400 D1 3401 C1 3402 C1 3403 C1 3404 C1 3405 C2 3407 C2 3408 C2 3409 C2 3410 D1 3413 C2 3415 D2 3418 D11 3419 D11 3420 D11 3421 D11 3422 B5 3423 B5 3424 B5 3425 D1 3426 D1 3427 B6 3428 B5 3429 D1 3430 D1 3431 B10 3432 D1 3433 D1 3434 D8 3435 B6 3436 B5 3437 B10 3438 B10 3439 B5 3500 C11 3504 C11 3506 G9 3507 G9 3514 C1