Acer AL702SG Schematic

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Page 1

AL702 Service G uid ervice

17-inch LCD Monitor

Page 2

AL502

1. Audio circuit (Circuit diagrams Main PWB)

1.1 Au dio input Th e audio signal input recei v ed from the audio input terminal (JK011) is appl ied to the amplifi er I001 of 4 (LCH) an d 9 (R-CH) through the low-pass filt er consis tin g of R040, R041, R042, R043, C040 an d C041. In this amplifier, controls of Volume and mute are conducted. The audio signal controlled at the pin 6 determines th e attenuat ion of output of the amp lifiers. Since then, th e signal is output to th e jack P003.

1.2 Au dio output Th e audio s ignal is output from P002 output terminal of the Audio block to the internal speaker system.

2. Power supply (Circuit daigrams MAIN PWB)

2.1 Line fil ter c onsist s of C801, T801, C802, C803, C804. It eli min at es hig h frequen cy interference to meet EM I’s req uirement.

2.2 Rec & Filter :

Bridg e diode D801 converts AC source into pu lsed DC. This pulsed DC is smoothed an d filtered by C805. R802 is an NTC ( negative thermal coefficient ) resistor, used to reduce inru sh current to be within safe range.

2.3 Powe r tran sformer :

T802 c onverts energy for square wave from power source C805 to secondary s ide to generate +12V and +5V.

2.4 Ou tput :

Th e square wave from T802 is rectified by D809, D810, then filtered by C817, C822 to generate +12V and +5V res pectively.

2.4.1 A 5V power supply f or LCD modu le, CPU and logic i s g enerated from the power sou rce.

2.4.2 I308 : 3-terminal reg u lat or

A 3.3V power supply f or I306 an alog is generated from t h e 5V source.

2.4.3 I308 : 3-terminal reg u lat or

A 3.3V power s upply for I306 digital is generated from th e 5V source. Q302, Q303 ON/OFF cont rol for LCD Modu le ON/OFF con trol is performed for power ON/OFF and also for the power saving sequence.

2.5 Driv er :

Q803 drive T802 from PWM control of I801 for power convert ed.

2.6 FB :

Neg ative feedback CKT consi sts of photo coup ler I802 and adjus table regulator I803. It can maintain output v olt ages +5V and +12V at a stable level.

2.7 PWM :

2.7.1 Start : When power is t u rned on, Q801 conducts due to bias from C805 and R805,R803. C807 is charged a 16

v olt and a starting current abou t 0.3mA to pin 7 of I801. I801 starts to oscillate and outputs a pulse train th rou gh pin 6 to drive Q803.

2.7.2 OPP : Wh en Q803 turn s on, C805 supplies a linearly increasing tri angle current through th e primary induc

tan ce of T802 to the driver Q803, once th e peak value of this curren t multipl ied by R811 exceeds1 volt, pulse tra in will be shut down i mmediat ely to protect Q803, T802 from being burned out.

2.7.3 Regulation : If ou tput voltage +5V goes up, the R terminal of I803 gets more bias, accordingly photo transis

tor an d photo diode flows more cu rrent. The voltage of pin 2 goes up too, making the pulse width of pin 6 to become n arrower. So t he output voltage +5V will be pulled down to a stable value.

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AL502

2.7.4 OVP : If +5V g oes up too much, the induced voltage on pin 4 of T802 becomes large al so. Suppose that it is ov er 18 volts, ZD801 conducts, pin 3 of I801 is pulled up over 1 volt. The pulse train at pin 6 goes down to zero, s h uttin g Q803 off immediately.

2.7.5 SCP : If ou tput terminal is short to ground, photo transistor does not conduct, hence Q806 does not conduct either. Then oscilla tion of I801 is stop, sh utting Q803 off immediat ely .

H15AAU / H15AAR Power Board Block Diagram

Line Filter

Rec. & Filter

PWM Driver

Power Transformer

Output Rec. & Filter

3. On-screen circuit (Circuit diagrams Main PWB)

I300 Emb eded f u ncti on. On -screen menu screen is established and the resultant data are output from I300 (Circuit diagram MAIN PWB).

4. Video input circuit (Circuit diagram MAIN PWB)

Th e AC-coupled video signal is used to clamp th e black level at 0V).

5. Definition converter LSI peripheral circuit (Circuit diagram MAIN PWB)

I301 MRT V2 gmZAN1 is the defi n ition A/D con verter LSI. Th e analog R, G, B signal input entered from the video input circuit i s convert ed in to t he digital data of v ideo s ign al throu g h the incorporated A/D converter. Based on t his conversion, this device performs i nterpolation du ring pixel extension. The source voltage for this device is 3.3V and the sy stem clock f requ ency is 12MHz. Th e with stand voltage level for the input signal voltage is 3.3V and 5V.

6. System reset, LED control circuit (Circuit diagram MAIN PWB)

6.1 Sy stem reset

Sy stem reset is performed by detecting the risin g and falling of the 5V source voltage at I302.

6.2 LED control circ uit

Gre en / amb er i s li t with t h e control s ignal of th e LED GREEN and LED A M BER sig n al p in 43, 42 from I303 (Circui t diagram MAIN PWB).

7. E2PROM for PnP (Circuit diagram MAIN PWB)

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8. E2PROM (Circuit diagram MAIN PWB)

Data trans fer between I304 and CPU (Circui t diagram MAIN PWB page 4/7 (I303) is effected throu g h the IIC bu s SCL (pin 9) and SDA (pin 8) of I300 or SCL (pin 42) and SDA pin 39 of I301. The data to be transferred to each device are stored in I304.

n I300 control data. n OSD related s etting data. n Other con trol data for serv ice menu.

9. CPU circuit (Circuit diagram MAIN PWB)

I303 (MTV312M64) (SM89516C25) or (W78E62BP-40) fun ctions as the CPU. Th e source voltage for th e device is 5.0V and the system clock frequ ency is 12MHz.

9.1 Detection of POWER switch status Th e CPU identifies the ON status of the two power supp lies. The identification is made when the power supply is turned off. For example, if the power supply is turned off with the POWER switch, the POWER switch must be tu rned on when activating t he power supply again. If the power supply is turned off by pull in g out the power cord , then th is power s upply can be turned on by con necting the power cord, wit hout pressing the POWER s witch.

9.2 Dis pl ay mode i den tification

9.2.1 Functions (1) Dis play mode identification

n The display mode of input signal is identified based on Table 1, and according to the frequency and polarity

(HPOL, VPOL) of h orizontal or vertical sync signal, presence of the horizontal or vertical sync signal, and the discriminati on sig n al (HSYNC_DETECT, VSYNC_DETECT).

n When the mode has been identified through the measurement of horizontal and vertical frequencies, the total

n umber of lines is determined with a formula of “ Horizont al frequ ency / Vertical frequency = Total number of lin es. “Fin al i den t ificatio n can be made by examini n g t he coincidence of th e obtain ed figure wi th the n umber of lines for the mode identified fro m the frequ en cy.

n When the detected frequency if the sync signal has changed, the total number of lines should be counted even

th rough it is rge ident ified frequency in the same mod e. Then, it is necessary to examine whether th e preset v alue for the vertical dis play positi on o f It em 4-3 has exceeded th e tot al number of lin es. If e xceeded, a

maximu m value shoul d be set up, which does n ot exceed the vertical display pos ition of Item 4-3. (2) Ou t-of -range Th is out-of-range mode is assumed when the frequency of the horizontal / vertical signal is as specified below.

n Vertical frequ ency : Below 50Hz or above 85Hz n Horizontal frequency : Bel ow 24 KHz or above 75 KHz

AL502

(3) Power s ave mode Th e power save mode is assumed when the horizontal / verti cal signals are as specified below.

n If there is no horizon tal sync signal input. n If there is no vertical sync signal input. n If the horizontal sync sig nal is outside th e measuring range of I300. n If the vertical sync sign al is outside the measuring range of I300.

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Table 1

Pin No.

Signal name

Mode

H-

freq

(

KHz)

Band Width

31.47

37.86

35.16

37.88

46.88

48.08

49.72

48.36

52.45

56.48

60.02

AL502

No Resolution

(MHz)

1. 247 VGA 720 x 350 70Hz

2. 102 VGA 720 x 400 70Hz

3. 103 VGA 640 x 480 60Hz

4. 182 MAC 640 x 480 66Hz 35 32.24 - -

5. 173 VESA 640 X 480 72Hz

6. 109 VESA 640 X 480 75Hz 37.5 31.5 - -

7. 104 VESA 800 x 600 56Hz

8. 116 VESA 800 x 600 60Hz

9. 110 VESA 800 x 600 75Hz

10. 117 VESA 800 x 600 72Hz

11. 108 MAC 832 x 624 75Hz

12. 118 VESA 1024 x 768 60Hz

13. 217 SUN 1024 x 768 65Hz

28.322 + -

28.322 - +

25.175 - -

31.5 - -

36 + + 40 + +

49.5 + + 50 + +

57.283 - 65 - -

70.49 - -

Polarity

H V

14. 157 VESA 1024 x 768 70Hz

15. 141 VESA 1024 x 768 75Hz

Atten tion :

1. Wh en resolution beyond 1024 x 768 is inpu tted, resolution is lowered with Down scaling to 1024 x 768, and in dicat ed, and OSD should indicate OUT of Range.

9.3 Us er Control

9.3.1Related ports of I303

Port

P1.5 7 I POWER Power switch input Power ON , OFF

P1.1 3 I DOWN switch input ( ) key P1.0 2 I UP switch input ( ) key P1.3 5 I - - switch input ( - ) key P1.2 4 I + + switch input ( + ) key

I/O

Function Remarks

75 - -

78.75 + +

control

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9.3.2 Functions

Pin No.

Signal name

Pin No.

Signal name

Con trol is effected for the push-switches to be used when the user changes the parameters, in order to modify the res pecti ve setting values. Whether the s witch has been pressed is identi fied with the switch input level th at is tu rned “L”. Each switch in put port is pulled up at outside of ASIC. Each parameter is stored i n the EEPROM, the contents of which are updated as required.

9.4 Con t rol of defini tion converter LSI I300.

9.4.1 Ports related to control

AL502

I/O

159 I IRQ interrupt signal

5 I/O SCL serial clock 6 I/O SDA serial data

9.4.2 Functions Majo r functi on of I300 are as foll ows: (1) Expansion of the display screen. (2) Timing control for various signal types. (3) Power-s upply sequence (LCD panel).

9.5 I2C bu s control

9.5.1 Re lated ports of I303

Port

P1.7 14 O SCL IIC bus clock P1.6 13 I/O SDA IIC bus data

9.5.2 I2C-con trolled functions Th e following functional controls are effected by I2C. (1) Con t rol o f EEPROM I304 for p arameter setti ng.

I/O

Function

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9.6 Power ON s equence

POWER

D-SHCLK

DATA

Wh en the POWER switch is pressed, the POWER OFF signal is turned “H”. When this “H” potential is detected, th e CPU begins to establish the respective power supplies according to the sequence shown below.

PPWR

INV_EN

LED

AL502

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9.7 Power OFF s equence

POWER

D-SHCLK

DATA

Wh en the POWER switch is pressed while the power su pply is ON, the POWER ON signal is turned “H”. When

ts hown below.his “H” potential is detected, the CPU begins to turn off the respective power supplies according to the sequence

PPWR

INV_EN

AL502

LED

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AL502

10. Inverter

Th is unit operates on an output v oltage of 15V from po wer source.

10.1 Regulator: Q101 get a +5VDC for I102 power supply.

10.2 UVP: Q106 tu rns off when the Vin is under 14V. Then pin 3 of I102 is pulled low and inverter off immedi ately. Th at is the under voltage protection.

10.3 Co ntrol IC: I102 (OZ960S)

10.3.1 Enable : Wh en pin 3 of I102 is ov er 1.5V, I102 works. If it is under 1.5V, I102 tu rns off.

10.3.2 OSC: When I102 enabled, R108/C115 (pin 17/pin18 of I102) dete rmine the operat ing frequen cy .

10.3.3 SST: C104 (pin 4 of I102) provides soft start funct ion .

10.3.4 Ignit ion : R109 (pin 8 of I102) provides higher operatin g frequency for more striking vol tag e unt il regulation

of f eedbac k of l amp cu rren t. C103 (pin 1 of I102) determi ne the striking time.

10.3.5 Dimming control: The di v ided voltage of R106/R105/R104 control the duty pulse of burst-mode to drive Q105

and perform a wide di mmin g control for the CCFL. T he burs t-mode frequ en cy is d etermin ed by C116.

10.3.6 Regu lation : Pin 9/pin 10 of I102 provide regulat ion of t h e CCFL curren t from feedback. Th e n on-inverting

reference (pin 10 of I102) is at 1.25V nomin al.

10.3.7 Protecti on : Open-lamp protection in t he ignition period is provided through both pin1 and pin 2 of I102.

Remov al of th e CCFL during normal operatio n will tri gger Q104 to turns on and shu ts off the inverter. This is latch f unction.

10.3.8 Output drivers: The configuration prevents any shoot-through issue associated with bridge-type power

con version applications. Adjusting the overlap conduction between I101 P-MOSFET and I103 N-MOSFET, I101 N-MOSFET an d I103 P-MOSFET, the CCFL curren t reg u lation is achiev ed.

10.4 Fu ll-bridge swit ching /Transformer: I101/I103 /C123/C125/T101/T102 compose f ull-bridge swit ch ing to

con vert DC into AC for driver the CCFL.

10.5 Detection : C124/C119/CR102 detect the output voltage and ensure a rated voltage by pin2 of I102. Q102/Q103

en sure not a open -lamp.

10.6 Feedb ack: CR101/R120/R121/D108 sense the l amp cu rren t for neg ativ e feedback and regulation. The di vided

voltag e on R121 will be at 1.25V.

Inverter Board Block Diagram

VCC

Regulator

VDD

ON / OFF

Brightness

control

Control IC : OZ960

U.V.P. Enable

OSC

SST

Dimming

control

Output driver

Protection

Ignition

Regulation

Full-bridge switching

Transformer

Detection

Feed back

Lamp

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1. No display of screen (Screen is black, color of LED is amber)

Does OSD display when

you push key button.

When a signal isn't being inputted, it is

indicated with "VIDEO

INPUT". It is indicated

with "OUT OF RANGE"

at the time of the

frequency that it can't be

distinguished.

Check if the sync signal from Computer

is output and if the video cable is

Yes

connected normally.

Proceed "No OSD display"section.

ALC502

Proceed "Checking the resolution change

IC movement" section.

Input the sync signal of computer, or

change the cable.

Trouble Sh ooting Page 1

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2. Nothing displays on screen (Screen is black, color of LED is green)

Is backlight lit?

NG Refer "Checking the backlight unit" section

ALC502

Does computer output RGB video signals?

Check OSD menu is displayed on screen

when you push the "PROCEED" key.

Check the video cable for failure. Check the host for

output signal with all black only.

1) Change pattern of video signal output on the host.

2) Reconnect the video cable.

3) Change the video cable.

Proceed "Abnormal screen" section.

Page 2 Trouble Sh ooting

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Continue

2) Printed wire broke between I302 and P303 pin 44.

2) Printed wire broke between I300 and P303 pin 38.

2) Printed wire broke between I300 and P303 pin 40.

Check the 3.3 V power are supplied on I308 pin 2.

Check if the voltage on I308 pin3 that

is high level DC at 5V.

Failure point

ALC502

Failure point

1) Printed wire broke between P301 and I308

I308 Failure

Is a dot clock being outputted under the

condition that a LCD module is connected to

Check the H-sync pulse of negative polarity is

output on P303 pin 38 at TTL level.

Check the V-sync of negative polarity are

P303 pin 44?

output on P303 pin 40.

Failure point

1) I300 failure

Failure point

1) I300 failure

Trouble Sh ooting Page 3

Failure point

1) I300 failure

Page 13

Continue

Check the data enable of positive polarity

are output on P303 pin 42.

Check the data signal output on P306 and

P303 R, G, B data pin.

ALC502

Failure point

1) I300 failure.

2) Printed wire broke between I300 and P303 pin 42.

Failure point

1) The cable broke between P303 , P304 and LCD module.

2) LCD module failure.

1) I306 failure.

2) Printed wire broke between I300 and P303 , P304 data line

Page 4 Trouble Sh ooting

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3. Checking the back light unit

Is +15V supplied to P803

pin 3, 4 to inverter PWB?

ALC502

Check the INV_EN signal of the rectangle input I307 pin 5 at TTL high level

Check the PWM signal of the input from I303 pin 7 is a BRI signal

Inverter cable disconnection.

Failure point

Is a "H" level being output in the TTL level from I300 pin 143

Or, is INV_EN signal of the rectangle being output?

Failure point

Printed wire broke between I300 pin 143 and I307 pin 5

Failure point

1) Inverter cable disconnection.

2) Inverter of LCD module failure.

Failure point

1) Printed wire broke between I303 pin 17 and I307 pin 3

2) I307 failure.

Trouble Sh ooting Page 5

Page 15

4. Abnormal screen

ALC502

Check the R, G, B video signal from computer input on

Check the R, G, B input signals on I301 pin 12, 20, 28,

Is the pulse of the TTL level being output to P303, P304

Check the negative horizontal sync pulse output to P304

D-Sub R, G, B connector.

respectively that their level is 0.7Vp-p maximum.

from the data line of I300?

pin 38 from I300 pin 80 at TTL level.

Failure point

1) No R, G and B video signal output from host computer. Check computer

2) Video signal cable disconnection.

Failure point

In case of the Red signal. (A Green and Blue signal is the same path, too.)

1) Printed wire broke between D-Sub(R) and I301 pin 12.

2) R341 short.

3) C321 open.

4) R362 open.

Failure point

1) Printed wire broke between I300 data line and P303, P304

2) I317 failure.

Check the negative vertical sync pulse output to P304 pin

40 from I300 pin 75 at TTL level.

Check the positive DE pulse output to P304 pin 42 from

I300 pin 74 at TTL level.

Check the SHFCLK OUTPUT to P304 pin 44 from I300

pin 44 at TTL level.

Process "Checking the resolution change IC movement"

section.

Failure point

1) Printed wire broke between I300 pin 80 and P304 pin 38.

2) R351 open

Failure point

1) Printed wire broke between I300 pin 75 and P304 pin 40.

2) R352 open

3) C416 short

Failure point

1) Printed wire broke between I300 pin 74 and P304 pin 42.

2) R355 open

3) C382 short

Failure point

1) Printed wire broke between I306 pin 44 and P307 pin 44.

2) FB314 open

3) FB315 open

4) C380 short

5) C381 short

Page 6 Trouble Sh ooting

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5. NO OSD display

Check the input of pulse from I300 pin 5, 6.

Failure point

1) Printed wire broke between I306 pin 5 and I303 pin 9.

2) Printed wire broke between I306 pin 6 and I303 pin 8.

Proceed "Checking the resolution change IC movement" section.

ALC502

Trouble Sh ooting Page 7

Page 17

6. Abnormal plug and play operation

6.1 Abnormal DDC2

Confirm the input of serial data on I305 pin 6 synchronize SCLK at TTL level.

ALC502

Failure point

1) The host machine isn't communicating in DDC2 mode.

2) The video cable may have failed or may not to have connections for DDC.

3) Between I305 pin 6 and P302 pin 15 may have failed.

4) R337 open.

5) Cable failure.

Failure point

I305 failure.

Page 8 Trouble Sh ooting

Page 18

7. Checking the interface circuit of sync signal

7.1 Checking the control circuit of horizontal sync pulse

ALC502

Check the horizontal sync signal on I301

Process "Checking the resolution change IC

pin 94 TTL level.

movement" section.

1) Video cable may have failed.

2) Printed wire broke between P302 pin 13 and I301 pin 94

3) R346, R348 open

4) C372, C373 short

7.2 Checking the control circuit of vertical sync pulse

Failure point

Check the vertical sync signal on I300 pin

Process "Checking the resolution change IC

44 TTL level.

movement" section.

Failure point

1) Video cable may have failed.

2) Printed wire broke between P302 pin 7 and I300 pin 44

3) FB308, R343 open

4) C369 short

Trouble Sh ooting Page 9

Page 19

8. Checking the resolution change IC movement

Is there +3.3V supply on I300 pin 17, 21, 57, 77, 79, 97, 102, 117, 137, 154, 156, 157 and 65.

ALC502

Is 12MHz clock input to I300 pin 3 at

Is +5.0V supplied to I300 pin 2 at

Failure point

I300 failure

Proceed "Checking the DC/DC converter circuit" section.

TTL level?

Is 12MHz clock output from X300

OK NG

Print wire broke between X301 and

High level?

Check the output of 5.0V "H" pulse

from I302 pin 6.

NG Is 5.0V supplied to I302 pin 7?

at TTL level?

Failure point

I300 pin 3.

Failure point

X300 failure

Failure point

1) FB319 open

2) Power source

Failure point

Print wire broke between I302 pin 6

and I300 pin 2.

Failure point

I302 failure

Page 10 Trouble Sh ooting

Page 20

9. No power on

9.1 No power on (I)

Check output voltage +5V,

+15V is right or not.

ALC502

Check power switch is turn on

Check power cord ( P801), Signal cable

(P302),P802, P803, CN102, CN103

is connected right or not.

Check C805 is about DC

or not.

140V-330V or not.

Check C807 is over

10V or not.

It is not power board

problem.

Turn switch on.

Connect it right.

Check F801, D801, P801

and repair them.

Check R805, R803, I801

and repair them.

Check pin 6 of I801 have

same pulse or not.

Check pin 1 of T802 have

same pulse or not.

Check peak voltage of R811 triangle

pulse is up to 1 volt or not.

Check D809, D810, C816, C821, T802

have same short circuit, or the output

+5V, +15V is over load.

Check feedback circuit around I802,

I803 and the other components

and repair them.

Check peripheral components

of I801 and repair them.

Check Q803, R813, R814, D806

, R812 and repair them.

Check D804, R807 and

repair them.

Repair them.

Trouble Sh ooting Page 11

Page 21

9.2 No power on (II)

ALC502

Check the + 5V power is supplied

from power source.

Is LED turned on in amber

momentarily when a power button is

pushed?

Proceed "Checking the operation of

CPU".

Failure point

Power source failure.

Failure point

Power source failure.

Page 12 Trouble Sh ooting

Page 22

10. Checking the DC/DC converter circuit

ALC502

Check the output of 3.3V line voltage

from I308 pin 2.

Is the output FB321 being inputted

Printed wire broke between I308 pin 2 and I300 power supply pin.

to I308 pin 3?

Failure point

I308 failure

Failure point

Printed wire broke between I308

pin 3 and output of FB322.

Trouble Sh ooting Page 13

Page 23

11. Checking the operation of CPU

Printed wire broke between output of FB320 and I300 power supply pin.

Is there +5.0V supply on I303 pin 44

ALC502

Is 12MHz clock input to I303 pin 21

and 20 at TTL level?

Check the input of 5V "H" pulse from

I310 pin 4 are same as I303 pin 10.

(14 msec Typ)

I303 failure.

1) Printed wire broke between I310 pin 4 and I303 pin 10.

Failure point

X301 failure.

Failure point

Page 14 Trouble Sh ooting

Page 24

12. Checking the audio circuit

Is a cable with the

host PC connected?

ALC502

Aren't the setups of the

host PC a minimum and off?

Is correct output waveform being inputted from JK011

pin 2, 3 of the host PC?

Is the waveform which is the

same as JK011 being

inputted to I001 pin 4, 9?

Is output wavefrom being

outputted in I001 pin 14, 17?

The setup of the host PC is changed.

1) Printed wire broke between JK011 pin 2, 3 and I001 pin 4, 9.

2) R040, R041 open.

3) R042, R043 short.

4) C040, C041 open.

Failure point

Audio cable disconntction.

Failure point

Audio cable disconntction.

Failure point

1) Speaker cable disconnection

2) Speaker failure

Is mute/STD-BY low level at pin 11,

Is Variable DC volume

Failure point

Is 15V supplied to I001 pin 15, 16?

pin 12.

control at pin 6.

I001 failure.

Proceed section 9.1 "No power on".

Proceed section 11 "Checking

the operation of CPU".

Check I002 pin 8 is 5V DC.

Proceed section 11 "Checking

the operation of CPU".

Proceed section 9.1 "No power on".

Trouble Sh ooting Page 15

Page 25

13. Checking inverter board circuit

Check Vin pin is around 15.5V.

Check Q101, D101, D104 and repair

Check Q106, D110 and repair them.

Check C115, R108, I102 and repair

Check Q102, Q103, CR101, CR103

On/off pin is over 2V.

Brightness pin is between 0V and 3.7V.

ALC502

Check pin 5 of I102 is 5V.

Check CN102, CN103 is connected

right.

Check pin 3 of I102 is over 2V.

Check pin 18 of I102 is triangle

pulse.

It is not inverter problem.

them.

Check CCFL and repair them.

them.

Check pin 4 of I102 there is soft start edge up to 4V and pin 11, 12, 19, 20

there is some pulse output.

Check pin 2 of I102 there is up to 2V

from output detection.

Check full-bridge (I101, I103, D102,

D103, C123, C125) work right.

Check transformer (T101, T102)

work right.

Check detection (C124, C118, C126,

CR102 and like those) work right

and repair them.

Repair I102.

and repair them.

Repair them.

Page 16 Trouble Sh ooting

Page 26

AL502

1. Recommended Parts List

Note: 1. The components identified by “ “ mark are cri tical for X-ray safety. Replace these with

only the same parts specified.

2. The components identified by “ * “ mark are critical parts.

3. There is only OTP IC at the model beginning (FPR stage or before). When it put in mass production and there must be Mask coming out. Please checkyou have spart parts need, please check BOM to get the last release part number and related information.

No. Location Part Number Description

1 *** I300 6447000406 IC MASCOT II CONTROLLER 160P PQFP 2 * I301 6447000506 IC VITESSEI 100P QFP 3 * I310 6446008108 IC NC7SZ04M5X SOT-23-5

4 ** I304 6448016508 IC EEPROM-24LC16B/SN SOP-8

5 ** I301 6447000506 IC ASIC-VITESSE2-100P-QFP 6 ** I307 6442001978 IC LM358DR 8P SOP

7 * I308 6442023326 IC AIC1084-33CM 3P T0263

8 *** Q300 6442007208 TR NPN SST2222A SOT-23 9 ** Q302 6427002508 FET-P-CHNL SI2305D3 SOT-2-3

10 *** Q303 6442007308 TR NPN SST3904 SOT-23

11 *** I001 6442023100 IC LINEAR-TDA7496L PDIP

12 * I303 6448018900 IC CPU SM89516C25J PLCC44P

Recom m end ed Spare Parts List Page 1