HP

D8891A

14 Mon

itor chassis : JD

144K-H

P

Service M

anu

al

5. B

LO

CK

DIA

GR

AM

5-1. MA

IN &

VID

EO

BO

AR

D

IC101H & V SyncProcessor &

modes detector

Power managementdetector

Switchingmodem

Power supply&

Power savingcircuit

Degaussingunit

Audiosignal

I/P

Audioamplifier

&DC Volumecontrol unit

ACI/P

14" colorCRT &

Deflectionunit

TLS1233Video

Preamplifier

24LC21Display

DataChannel

unit

R.G.B.OutputStage

R

G

B

H-

V-

SCL

SDA Video board

TDA4852Horizontal &

Vertical sync -Processing unit

B+

+75V

+12V

+6.3V

+5V

Audio powerSupply

TDA7057AQ

Internalspeakers

&external

Ear phone

HorizontalDeflection unit

&EHT

Horizontal Size&

E/W correction

TDA4866Vertical

output stage

V-O/P

H-O/P

IC802BOOST

CONVERTER

IC902OPTIONAL

Main board

HP

D8891A

14 Mon

itor chassis : JD

144K-H

P

Service M

anu

al

5-2. SP

S

SYNC CKTFROM FBT30KHz~48KHz

PWM CONTROL CKT

UC3842B IC801

MAIN SWITCHQ80

1

EMI CKTAC I/P

100Vac~240Vac

I/P RECTIFIER

& FILTER CKT

FUSE

PWR X'MER

T801

RECTIFIER

OUTPUT CONTROL

CKT

DC VOLTAGE OUTPUT

FROM IC101

5

.

0

V

6

.

3

V

1

0

V

1

2

V

7

5

V