Kenwood KACPS-1-D, KACX-1-R Service manual

POWER AMPLIFIER

KAC-PS1D/X1R

SERVICE MANUAL

KAC-PS1D

KAC-X1R

KAC-PS1D only

Fuse (25A) (F52-0014-05)

Remote control (X16-6000-10)

KCA-WR10

Dressing Panel (A21-6576-01) : KAC-X1R (A21-6577-01) : KAC-PS1D

Modular cable (E30-6240-15)

Mouting hardware (J22-0301-14)

KAC-PS1D

KAC-X1R

Screw set (N99-1766-05)

Screw set (N99-1795-05)

This product uses Lead Free solder.

KAC-PS1D/X1R

(X08-431)(X09-856)

SENS. V OL

VR1

LINE IN

(0.2-5V)

R ISO-AMP

LINE OUT SEL.

LINE OUT

IC10,11

ISO-AMPL

IC10,11

BLOCK DIAGRAM

IC2

IC3

IC1

L/R MIX

IC55-57

BASS BOOST

IC6

I.N.V I.S.F

I.N.V SEL.

L.P.F

(400Hz)

IC4

L.P.F

VR3 VR4

IC7

FREQ

(15-60Hz)

L.P.F SEL.

FREQ

(40-200Hz)

I.S.F SEL.

IC8

B.R.F

-12dB

IC24

1 LIMIT

-6dB

FREQ

(40-200Hz)

Q101,102,131

MUTE ATT

B.R.F SEL.

REM

LEVEL 0-18dB

FREQ

40-100Hz

IC13(2/2)

SUMMING AMP

IC20(1/2)

TRIANGLE WAVE

IC20 (2/2)

I.N.V

IC19(2/2,) IC6,7, Q179,180

DC-OFFSET DET

IC1

IC11(X08- )

DRIVER

IC14

COMP

IC15

COMP

Q174-178

OVERLOAD THERMAL DET

u-COM

TH1,2

DET

IC15,16

DEAD TIME

IC16,21

DEAD TIME

ROT ARY PUSH SW

Q44,45,157,189

LEVEL SHIFT

Q42,43,156,188

LEVEL SHIFT

Q150,151

D-AMP ON/OFF

Q25,26,

28,32

15V

AVR

Q50-53

FL AVR

Q159,164-167,

Q158,160-163,

Q31,33,34

+HB AVR

191,193

DRIVE

190,192

DRIVE

BATT. CURRENT

IC3

DC/DC CON

Q1,2

POWER ON/OFF

Q3-5

+5V AVR

Q170,171,

186,187

FINAL MOS-FET

Q168,169,

184,185

FINAL MOS-FET

IC13(1/2)

NF AMP

POWER INDI.

BA TT. VOLT

(to u-COM)

LC FILTER

Q37,38,83

FAN AVR

FAN

LC FILTER

600W/4

1200W/2

1200W OVER/1

P-CON

BATT.

GND

(BTL)

SP-OUTPUT

KAC-PS1D/X1R

COMPONENTS DESCRIPTION

● AUDIO UNIT (X09-8560-10)

Ref. No. Application / Function Operation / Condition / Compatibility

IC1 µ-com Overall control. IC3 DC/DC converter driver Generates the gate waveform for switching.

IC5 (2/2) Comparator

IC6 (1/2) Comparator Detects ASO. Compares current with voltage to detect short in the output.

IC6 (2/2) Comparator

IC7 (1/2) Comparator

IC7 (2/2) Comparator

IC10,11 Isolation AMP Removes the common mode noises in the input signal. IC12 Buffer AMP Buffer AMP for RCA output. IC13 (1/2) Signal amplification IC13 (2/2) Signal amplification IC14 (1/2), Comparator, IC20 (1/2) Signal amplification

IC14 (2/2) Comparator

IC15,16,21 NAND gate To gate pulse of the D-class amplifier.

IC17 NAND gate

IC18 Signal amplification

IC19 (1/2) Signal amplification

IC19 (2/2) Signal amplification Amplifies the DC offset at the SP + terminal, and applies to the DC servo. IC20 (2/2) Signal amplification

IC22 Filter

IC24 Signal amplification

IC55~57

Q1,2 POWER ON SWITCH

Q3~5

Q6 SW5V control Turns ON/OFF 5V to the SW5V line in response to the output from pin 20 of the µ-com.

Q7 Pcon over voltage control

BassBoost circuit Boosts the signal with the operations from the remote control. (Remote control operation) GAIN=0~+18dB, fc=40~100Hz

5V constant voltage power supply

Compares the analog signal with the triangular wave and generates the PWM waveform for the minus output-side amplifier of the BTL.

Detects the resonance waveform that is caused when the plus and minus terminals are shorted in the vicinity of the SP terminals, and protects from the short. Detects over current with the waveform shaped in IC17 and sends the result of the detection to the µ-com and the TR used to control the D-class amplifier. When SP+ or SP- terminal output is shorted to the ground, the current in the + power supply and that in the - power supply are unbalanced. The unbalance in the current is converted into DC voltage in Q176 and Q177, and when the voltage exceeds the preset value the output is reversed and the protection function is activated.

Amplifies the output voltage between the SP + and SP - terminals and generates the NF signal. Amplifies differences between the input and feedback signals. Initial stage of the D-class amplifier.

Triangular wave generation.

Compares the analog signal with the triangular wave and generates the PWM waveform for the plus output + side amplifier of the BTL.

Retains the pulse width and keeps holds a certain width when IC6 and IC7 (2/2) detect its individual over current. Amplifies and rectifies the output voltage at the SP + terminal, and generates DC voltage that is proportional to the output. Amplifies the potential differences caused by current running in the GND pattern, and sends it to the µ-com to obtain current.

Generates the inverted waveform of the triangular wave that is generated in IC14 (1/2) and IC20 (1/2). Filters and rectifies the resonance waveform that is caused when the plus and minus terminals are shorted in the vicinity of the SP terminals, and sends the resultant DC voltage to IC6 (2/2). When 1Ω load is detected, lowers the voltages at pins 1 and 7 and decreases the signal clipping level in order to limit the SP output.

Turns ON/OFF DC/DC converter power supply in response to the output from pin 8 of the µ-com.

It is used as the constant voltage power supply of 5V for the µ-com and the SW5V.

Blocks the ON signal to the Pcon and places the Pcon in the OFF condition when the battery voltage is too high.

KAC-PS1D/X1R

COMPONENTS DESCRIPTION

Ref. No. Application / Function Operation / Condition / Compatibility

Q8 Pcon Switch

Q10,11 DD converter gate control

Q13~16 DD converter gate driver Drives the switching FET gate in the DD converter. Q17~20, Q22~24,27 side.

Q25,26

Q28,32

Q29,30 voltage power supply is

Q31,33,34

Q36~38, Q41,83 Darlington connection in Q37 to turn ON/OFF by the µ-com.

Q39 Limiter level control

Q42~45, Q156~167, PWM shaping circuit Generates the pulse signal for the gate drive of the high side and low side. Q188~193 Q168~171, Q184~187 Q47,48 Power supply SW for FL Turns ON/OFF the FL power supply from pin 22 of the µ-com.

Q50~53

Q54,55

Q101,129 MUTE Mutes the audio signal from pin 56 of the µ-com to prevent applying the shock noise. Q102, Q131~133 increases. For 1.5dB respectively.

Q125,126 ADV

Q150,151 D-SW Turns ON/OFF the D-class amplifier stage from the µ-com or protection. Q179,180 DC detection Turns ON when DC is detected at the SP terminal and sends it to pin 64 of the µ-com. Q181,182 ASO detection Voltage amplification circuit used when the ASO is detected Q174, Q176~178 protects against the ground fault. Q175 ASO detection Current amplification circuit used when the ASO is detected Q603 LOGO-LED Turns on the LOGO LED from pin 4 of the µ-com.

DD converter switching FET

+15V constant voltage In order to compensate HFE in Q26, both TRs in Q25 are connected with the Darlington power supply connection and the constant voltage of +15V is obtained.

-15V constant voltage In order to compensate HFE in Q28, both TRs in Q32 are connected with the Darlington power supply connection and the constant voltage of -15V is obtained. Tracking when -15V constant

turned OFF +15V constant voltage power supply for high voltage

Power supply for F AN

FET for output Generates the PWM output waveform by the switching.

Constant voltage power supply for FL filament Constant voltage power supply SW for FL filament

ATT

Ground fault detection

Places the amplifier in the ON condition by sending “L” to pin 1 of the µ-com when the Pcon terminal becomes “H” while the battery voltage is in the normal range. Turns ON/OFF DD converter gate drive pulse in response to the output from pin 8 (Power_On) of the µ-com.

Repeats switching the transformer’s primary side to generate high voltage at the secondary

Adjusts the voltage drop in the -15V constant voltage power supply to the voltage in +15V side while the power OFF.

Power supply for the gate drive signal in the output FET high side.

In order to compensate HFE in Q38 and Q83, Q41 and Q36 are connected with the

When 1Ω load is detected, CEs are ON and the voltages at pins 1 and 7 of IC24 are dropped in order to limit the signal amplitude.

Supplies the constant voltage of 2.3V to the FL filament.

Turns ON/OFF the FL filament power supply from pin 22 of the µ-com.

Lowers the volume when temperature at the output FET or in the vicinity of the transformer

Reads the power supply voltage value to show it with the FL. Turns OFF when the power supply is OFF to save the backup current.

When SP+ or SP- output is shorted to the ground, sends the signal to pin 6 of the IC7 and

KAC-PS1D/X1R

COMPONENTS DESCRIPTION

● PREAMPLIFIER UNIT (X08-4310-10)

Ref. No. Application / Function Operation / Condition / Compatibility

IC1 (1/2) Signal amplification Mixes Lch and Rch to make Mono signal. IC1 (2/2) Signal amplification Buffer to send the signal that comes through LPF and Bass Boost to the Line Out. IC2 Frequency fixed LPF LPF fixed at 400Hz. IC3 Signal amplification Amplifies the signal that comes through SensVol and outputs it with low impedance. IC4 Frequency variable LPF LPF with variable frequency between 40~200Hz. IC5,6 (1/2) Band-cut filter Attenuates the frequency in the specific range between 40~100Hz. IC6 (2/2) Reverse circuit Changes the phase by 180 degrees. IC7 Frequency variable HPF Attenuates the frequency in the range of 15~60Hz that is lower than the specific frequency. IC8 (1/2) Signal amplification Amplifies the signal component to reduce noises in the subsequent BRF stages. IC11 FL driver Communicate with the µ-com, generates the data for FL display and reads in KEY.

MICROCOMPUTER’S TERMINAL DESCRIPTION

● MICROCOMPUTER: 78F0533GK011A (X09-856: IC1)

Pin No. Pin Name I/O Application

1 P_CON I 2 D_CURENT I Detects the D-class over current Enters into the protection operations. 3NCONot used Output L fixed 4 PON_ILLUM O LOGO LED+B SW H: ON, L: OFF, Initial condition “L” 5FAN1 O FAN rotation control q H: Rotation, L: Stop, Initial condition "L" 6 RESET I Reset 7 D_POWER O D-class amplifier power supply control H: D-class ON, L: D-class OFF 8 9 FLASH_W I Used when writing in the flash 10,11 NC O Not used Output L fixed 12 REGC 13 VSS 14 EVSS 15 VDD 16 EVDD 17,18 NC O Not used Output L fixed 19 NC O 20 5V_SW O SW5V ON: L L: SW5V ON, Initial condition “L” 21 NC O Not used Output L fixed 22 PON_FL O FL power supply (Grid and Filament) control H: ON, L: OFF 23~33 NC O Not used Output L fixed 34 ROTARY_CW I Encoder pulse input Detects pulse width

POWER_ON_1

Clears the stop mode by turning the P-CON ON

O Amplifier power supply control H: Amplifier power supply ON, Initial condition “L”

Truth Value

Table

Processing Operation Description

L: Clear the stop mode

KAC-PS1D/X1R

MICROCOMPUTER’S TERMINAL DESCRIPTION

Pin No. Pin Name I/O Application

35 36~38 NC O Not used Output L fixed 39 REF5V_OUT O Supplies to AVREF (pin 47) Output H fixed 40,41 NC O Not used Output L fixed 42 VFD_INH O Panel VFD driver INH Driver output switching 43 VFD_CE O Panel VFD driver CE Command control terminal of the driver 44 VFD_DATA_M O Panel VFD driver data line µ-com → driver input 45 VFD_DATA_S I Panel VFD driver data line µ-com → driver input 46 VFD_CLK O Panel VFD driver communication CLK Communication clock 47 AVREF - DA REF voltage Receives the reference voltage from pin 39. 48 AVSS -

49 IMP_DET I Detects load IMP at SP terminal

50 TEMP2 I

51 TEMP1 I

52 NC O Not used Output L fixed 53 AD_V I Detects BU voltage (For display) Displays the voltage and condition. 54 NC O Not used Output L fixed 55 AD_I I Detects primary current (For display) 56 MUTE1 O Mute control of the amplifier input stage L: MUTE1 ON, H: MUTE1 OFF, Initial condition “L” 57 NC O Not used 58~60 NC O Not used Output L fixed 61 ATT1 O Output signal level attenuation control L: Output attenuation, Initial condition “L” 62 ATT2 O Output signal level attenuation control L: Output attenuation, Initial condition “L”

63 LIMIT O

64 DC_DET I Output DC OFFSET voltage detection Enters into the voltage error protection operations.

ROTARY_CCW

IEncoder pulse input Detects pulse width

Temperature detection 1 (at output TR side) (For display and protection) Temperature detection 1 (at power supply side) (For display and protection)

Limits the peak value of the D-class amplifier input signal

Truth Value

Table

w Clips the audio signal quickly with “H”

Processing Operation Description

Reads the impedance and turns on the limiter when it is 1Ω load.

Displays the temperature and overheat protection.

Converts into the current and displays current value.

Truth value table

q FAN (Pin 5)

Calculated temperature based on the detected voltage at TMP_1 (pin 31) Note

Lower than 35°C Remains as L In the case of “H” output, it recovers to “L” when the temperature

35°C or higher H output decreases to 30°C.

w LIMIT (Pin 63)

Voltage detected at IMP_DET (pin 49) Note

Lower than 3.8V Remains as L

3.8V or higher H output

Recovers by P-CON OFF or RST.

TEST MODE

●

How to enter the test mode and how to c lear the test mode

• How to enter

In the backup connection condition (when the battery is being connected), turn ON the P_CON while keep pushing the rotary push key.

• How to clear

P_CON OFF or reset to clear the mode. (Clear the mode even in case of the protection.) * Do not clear the mode if the protection recovers automatically .

Turn

KAC-PS1D/X1R

● Items in the test mode and test operations

• INFORMATION display (Display of conditions)

In the test mode, the following items can be checked in addition to the normal INFORMATION display. Each item can be selected with the rotary encoder and the settings can be changed with the push key.

Additional items shown in the test mode

DIRG

Hz dB

Push

....

OVER

NAF

TTA

Hz dB

Push

OVER

Hz dB

Push

OVER

IMTIL

Hz dB

Push

OVER

Hz dB

OVER

Hz dB

OVER

Hz dB

OVER

Hz dB

OVER

Hz dB

OVER

FFO

Hz dB

OVER

Hz dB

OVER

0TTA

Hz dB

OVER

1TTA

Hz dB

OVER

2TTA

Hz dB

OVER

FFO

Hz dB

OVER

Hz dB

Turn

• Segment check of FL display tube Change the display segment in the following sequence of order. All on → GRID1 on → GRID2 on → GRID3 on → All of

• Check of FAN switching In the FAN switching mode, it is possible to select to rotate or stop the FAN regardless of the present temperature.

• Check of ATT switching In the ATT switching mode, it is possible to switch the ATT regardless of the present temperatur.

• Check of LIMIT switching In the LIMIT switching mode, it is possible to switch LIMIT regardless of the presently detected impedance of speaker.

OVER

Initial condition

in the normal mode

Condition display Items shown

OVER

DEL

REV

Hz dB

Push

OVER

Hz dB

OVER

TLOV

Hz dB

OVER

RTRUC

Hz dB

OVER

PMET

Hz dB

OVER

OMED

Hz dB

OVER

FFO

Hz dB

OVER

Hz dB

OVER

203.V

Hz dB

OVER

V34.1

Hz dB

OVER

A81

Hz dB

OVER

C87

Hz dB

Turn

• Check of LED switching In the LED switching mode, it is possible to select to turn on or off the LED.

•Version display It is possible to check the version of the µ-com.

KAC-PS1D/X1R

CIRCUIT DESCRIPTION

●

Short detection circuit between SP+ and SP- terminals

If the SP+ and SP- terminals are shorted in the vicinity of the terminals, the self oscillation occurs in the D-class amplifier. The oscillation in opposite phase is caused between the + and - terminals of the BTL, and this oscillation is applied to the differential amplifier, IC22 (2/2) to limit the amplitude with the zener diodes such that the voltage does not exceed the withstand voltage.

to COMPARATOR

from SP+ OUTPUT TERMINAL

from SP- OUTPUT TERMINAL

C207 0.01

C208 0.01

C198

3300P

C199

3300P

R339

47K

R340

47K

D173 D172

● Power supply circuit for FL

• V-FL V-FL is the power supply for grid of FL. D48 is used to select either the battery or +15V power supply that has higher voltage. The power supply voltage is set to constant 13V in D49. The power is turned ON/OFF with Q54 and is applied to FL driver.

• FIL+ Power is supplied by the battery and the voltage is set to 2.3V in D49 so that it is applied to the filament of FL. The power is turned ON/OFF in Q48 in response to the FLON signal from the µ-com.

TP5

R341 47K

The output from pin 7 of IC22 is rectified through the band pass filter whose center frequency is about 3kHz. The DC voltage generated after the rectification is applied to the comparator, (IC6 (2/2)) and generates “L” at pin 7 of IC6 when the voltage exceeds the preset threshold.

BPF

TP9 TP30

R345

2.2K

TP27

IC22(1/2)

C202

0.033

10K

R344

TP31 TP32

R3461KR347

C203

0.033

C204

D176

0.022

TP33

10K

R348

IC22 (2/2)

5 6

R342 47K

D174 D175

TP103

RESONANCE DET.

TP6

C200

0.01

R343

TP7

C201

0.033

22K

● Ground fault detection circuit

When SP+ or SP- output terminal is shorted to the ground, the current running in the +B power supply and that in the -B power supply are unbalanced. The current unbalance (±) is measured by R203 and R204 and the currents are mixed in R225. When the currents become out of balance due to the above shorting to the ground, the voltage is caused across R225. When this voltage exceeds the threshold decided by R256 and R257, the “L” output is generated at pin 7 of IC7. As a result, the over current protection operation is activated.

R73

Q50

D48

4.9V

Q48

22K

R99

100

R66

R87

4.7K

TP337

D49

Q47Q55

R307

R304

R80

Q51

R81

Q52

2.5V

R74 47

R72 47

Q53

47u25

R71 47

R79

2.2K

D46

C47

TP289

47u25

C46

14.4V

4.7

R88

4.7

R98

R89

13.4V

4.7

4.7 4.7

R90

R97

4.7

R96

4.7

R95

4.7

R94

Q54

4.7

R91

4.7

R92

4.7

R93

Q187

Q186

Q185

Q184

R203

0.01

R204

R213

3.3K

R223

3.3K

0.01

1.5K

R219

C172

0.047

Q174

Q176

C184 1000P

R259

R225 62K

33K

R226

Q177

Q178

0.047

R224

1.5K

C178

D165 D164

TP104

R257

R256

R820

10K

TP383

5 6

7 8

TP105

IC7

V+

R292 10K

C183 0.01

R830

D169

V-

3 2

10K

R287

R291

TP385

10K

TP384

R286

0.01

C189

D171

KAC-PS1D/X1R

IC14

IC19(2/2)

D137D138

D117

D115

D119

D118

D116

D114

(1/2)

IC20

TP57

TP52

TP53 TP55

TP60

TP54

TP102

TP101

5 6

C136

150K

R338

100K

R337

C135

10K

R151

6.2K

R149

6.2K

R148

6.8K

R146

0.01

C127

10K

R147

R803

10K

R145

330P

C126

R804

10K

R142

0.01

C503

0.01

C504

V+

243

V-

TP100

470K

R336

from SP+ OUTPUT TERMINAL

TRIANGLE WA VE GENERATE CIRCUIT

CIRCUIT DESCRIPTION

● Pulse shaping circuit

When either output from the ASO detection (IC6-pin 1), ground fault detection (IC7-pin 7) or short detection (IC6-pin 7) is “L”, the pulse with a constant width of about 10msec is generated even if the input pulse width is small. The input to the pulse shaping circuit is pin 5 of IC17 and the output from the circuit is pin 3 of IC17.

2.2K

R217

18K

R233

● Servo circuit

Amplifies DC offset voltage that is output to SP+ terminal in IC19 (2/2). Feedbacks the output from pin 7 of IC19 to the triangular wave generation circuit. Corrects DC offset voltage at SP+ terminal towards 0V by incorporating the feedback in the triangular waves that are applied at pin 6 of IC14.

C184 1000P

D165 D164

TP104

R254

TP382

R253

D22

R49

C175

6800P

R257

R256

4.7K

15K

18K

R820

10K

TP383

D140

D170

IC7

5 6

7 8

V+

R292 10K

TP105

C183 0.01

IC6

5 6

7 8

V+

1.0V

COMPARATOR

TP106

V-

4 3 2

D171

4 3 2

TP108

R830

C189

R291

0.01

R290

10K

D169

10K

R287

R286

TP392

C185 0.68

R271

R272

TP384 TP385

10K

Q181

C186 0.01

R266 220K

PULSE SHAPING CIRCUIT

TP387

IC17 (2/4)

10K

TP386

C190

1000P

10K

R270

TP393

Q182

4 5

R269

TP388

C192

0.047

0.01

C191

TP391

TP394

R279

20K

IC18 (2/2)

R278

12K

0.01

C194

R282

R280

TP389

R296 10K

R281

1.3K

330K

TP395

R283

10K

R308

D167

20K

C197

D166

IC17(1/4)

1 2

TP390

100P

R284 20K

D168

C193

10u50

TP396

IC18 (1/2)

12 13

IC17(3/4)

IC17(4/4)

R285

2 3

C195

0.01 R822

20K

OUT

R821

C196

10u50

10K

R289

R288

24K

● LIMIT circuit

IC24 (1/2) is a voltage follower and IC24 (2/2) is a reverse amplifier that has no gain. Q39 is turned ON/OFF in response to H/ L of LIMIT (pin

63) from the µ-com. Voltage at pin 3 of IC24 becomes 2.2V and 5V in response to ON/OFF of Q39. When the u-com detects 1Ω load, the input signal is clamped at ±2.8V, in which 0.6V of vf from D205 and D206 is added, and peak value of the signal is limited.

● NF circuit

Differentially amplifies the signal in IC13 (1/2) f or the BTL output and applies negative feedback signal to pin 6 of IC13 (2/

2).

3.3K

R188 24K

C157

0.056

C171

0.015

C173

0.015

R187 24K

C160

0.056

86uH

R214

24K

86uH

R216

24K

R189 24K

R186 24K

+ SIDE PWM OUTPUT

- SIDE PWM OUTPUT

+15V

-15V

TP46

C122

R137

R136

47u25

INPUT SIGNAL

TP327

TP331

10K

R258

Q39

R328

TP329

10K

R327

5.1V

0.01

C42

13K

C301

R825

0.01

TP306

C300

0.01

R824

TP305

IC24 (1/2)

R323

2.7K

5.1V

D205

OUTPUT SIGNAL

TP330

R331

IC24(2/2)

R330

3.3K

6 5

D206

R134 15K

R135 5.1K

C123 0.1

TP47

470

R138 1K

R8291R828

IC13(2/2)

C124 56P

R139 1M

C817

0.01

C816

0.01

R140

10K

TP51

C158

1000P

10K

R141

TP49TP48

IC13(1/2)

R171

NF AMP

R173 3.3K

R183 12K

R184 12K

R174

NF SIGNAL

+ 21 hidden pages