Fukuda Denshi FCP-2155 ECG Service manual

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SERVICE MANUAL

Interpretive Electrocardiograph

FCP-2155

4R2044

FUKUDA DENSHI CO••LTD.

No part of this document may be copied

or transmitted in any form without the prior written permission of Fukuda Denshi Co., Ltd.

Manufactured in Japan

Foreword

We I~stup here the warning marks used in Fukuda operation and service manuals. When you service the FCP-2155, read this service manual thoroughly and pay attention especially to instructions bearing the following marks:

Warning Marks

Warning marks used in operation and service manuals and labelled

on the equipment have the following meanings:

Read them carefully to understand the meanings and make sure of

the significance of each particular.

This mark is used to indicate the direct hazards

~Danger

which may lead to the death or serious injury of the

person, may wholly damage the instrument or may cause fire hazard, unless the instructions written there are observed.

Warning hazards which may lead to the death or serious injury

~Caution

NOTE

Other Marks

This mark is used to indicate the indirect potential

of the person, may wholly damage the instrument or may cause fire hazard, unless the instructions written there are observed.

This mark is used to indicate the possible hazards which may lead to a mild or medium injury of the person, may partially damage the instrument or may erase data from the computer.

"NOTE" is not warning instructions but offers infor- mation to prevent the person from doinq erroneous servicing.

Notice to indicate general unspecific prohibited matters.

Notice to indicate general unspecific caution, warn- ing or hazard.

This service manual describes technical information on FCP-2155to

aid the service engineer in troubleshooting.

The manual is intended to be used by service engineers of Fukuda representatives and authorized technical staff concerned with medical elec- tronic equipment. Description includes repairing and assembling methods of each component unit of FCP-2155. For parts lists and diagrams, refer to the Part II of the service manual.

The service manual consists of the following nine chapters:

1. General Description The outline of FCP-2155, specifications and controls and indicators are described.

2. Circuit Description Circuit configuration and functions are explained.

3. Troubleshooting Troubles vs. causes and countermeasures are described.

4. Maintenance

Procedures to replace the power fuse, ROM and battery and to perform

self-test are described.

5. Periodical Inspection Inspection procedures to prevent troubles and ensure safe and com- plete operation of the instrument are described.

6. Circuit Diagrams

7. Assembly Diagrams

8. Electrical Parts Lists

9. Structural Diagrams

Caution

• Never remodel Fukuda medical electronic equipment.

• The service manual is intended for the service engineers of Fukuda representatives and the techni- cal staff concerned with medical electronic equip- ment. Servicing, reassembling and adjustment shall

be performed by autorized service engineers.

• Prepare proper facilities and tools when servicing.

• Be sure to follow the instructions of operation manual when operating the equipment. For operating precau- tions, refer to the operation manual.

~ Servicing Precautions

&. Listed below are the instructions of prohibit, danger, warning, and cau-

tion which are described in this service manual. When taking the proce- dure bearing the following mark, read the description thoroughly, then start the task.

Caution

When checking voltages and signals on circuits for troubleshooting, take sufficient care to avoid short circuit. Also take care of the AC input side of PCB-6238. Contacting it when the instrument is powered may cause an accidental hazard.

Caution

When replacing the power fuse, be sure to turn the power off and dis- connect the power cord from the wall outlet in advance.

Caution

When replacing the ROM, be sure to turn the power off in advance. Also take care to mount it in correct direction.

(page 3-2)

(page 4-1)

Caution

When replacing the battery, be sure to turn the power off and discon- nect the power cord from the wall outlet in advance.

Caution

Disassembling/Reassembling Precautions

• Be sure to turn the power off and disconnect the power cord from the wall outlet. Then start disassembling the equipment.

• When removing the main PC board, remove the Ni-MH battery in advance.

• Take care not to disconnect and connect the key panel and sensor board from/to the connector too frequently. Too frequent disconnec- tion and connection of these units may cause poor contact.

• Use proper screwdrivers to loosen screws.

• When reassembling, make sure all screws are tightened to original positions and all disconnected connectors are reconnected properly.

PC Board Handling Precautions

• PC boards are equipped with extremely sensitive devices to static electricity.

(page 4-2)

(page 4-8)

• PC boards are sensitive electronic assemblies. Take proper meas- ures for removed PC boards, e.g. put them in a conductive bag.

• Handle PC boards carefully. Giving an impact to them may damage devices mounted onto them.

• Never remove a PC board or connect the connector to it when sup- plied with power.

iii

Caution

If you find a value which exceeds the allowable level, be sure to let the user avoid using the equipment. If the user operates the equipment as it is, he/she may receive an hazardous accident.

(page 5-2)

Equipment Classification

The FCP-2155 is classified into the following equipment:

1. Protection against electrical shock Class I

2. Type against electrical shock Applied part: Type CF

3. Degree of protection against harmful water invasion

Other equipment

4. Degree of safety in using under air-inflammable anesthetic gases or oxygen/nitrous oxide-anesthetic gases Equipment used under an environment containing no inflammable

anesthetic gases or no inflammable cleaning agent.

5. Running mode Continuous running mode

External Labels

[1 I]

_cee.

Aura CAROINER

~ --''''''~.

'CP·2JS5

@I ...

w.o

-+-

....

(I~)

e»

RESE'

...

'1iE

,t.)

'Iff)

CfJ

STOP

IIt~

RATING Label

AUTO CARDINER

MODEL FCP-2155 VOLTAGE AC230V 50HZ 19VA

EWIPI£NIIYIl: SERIAlI(J.

CAUTION Label

OC9.6V 7W

INT-CF CassJ-CF

FUKUDA DENSHI

3-39-4. HONGO.IlU'lKYO-KU. TOKYO. JAPAN

CO~

cro.

CAUTION-To reduce the rIsk of electr'lC shock,do not remove cover. Refer servICIng to qualIfIed serVIce personnel.

DANG ER Label

WARNING Label

~----------------------------------------------~

DANGER-Rlsk of explosion if used rn the presence of

flammable anesthetics.

DANGER-Rlsqued'explosion.

pas

employer' en

presense d'aneslhesIQues Inflammables.

WARNING-RISk ofrir Replace fuse as marked.

e .

® FUSE Label

FUSE 250V 2xT500mA

(j)

Equipotential Ground

® POWER Label

230V'"

POWER)

® BATTERY Label

~ ~ Ni-MH BATTERY PACK

8-HRAAFO

(9.6V 1100mAh)

FUKUDA DENSHI

Made1n Japan

CO~

LTD.

CHAPTER

General Description

1. Outline '" 1-1

2. Specifications 1-1

3. Controls and Indicators 1-3

1. Outline

The FCP-2155is a multi-channel electrocardiograph. It measures and analyzes standard 12-lead ECG waveforms with high accuracy, then records analysis results and ECG waveforms.

Based on clinically improved diagnostic criteria, the analysis program classifies measured ECG waveforms by Minnesota codes, age group and sex for increased accuracy.

The recorder adopts a hlqh-density thermal print system to output clear

ECG waveforms and measurements, together with patient data on a 63mm

wide paper.

2. Specifications

Amplifier Section

Input circuit: Leads: Input impedance: Input circuit current:

Input level: Calibration voltage: CMR:

Floating above the ground Standard 12 leads, Cabrera leads 20MO min. (10Hz refereed to) 5 x10-8max.

±18mV min. 1mV within ±2% 100dB or more

Electrode voltage tolerance: ± 400mV min.

Time constant: 3.2 seconds. min.

Sensitivities: 1/4, 1/2, 1, and 2 cm/mV; manual/automat-

ic selection 20llV

p-p

max.

1V p-p 50/60Hz for 2 seconds

0.05 to 150Hz within - 3dB AC: - 20dB or lower at 50/60Hz EMG: -3dB (-6dB/oct) at 40Hz Drift: -3dB or lower at 0.5Hz

Internal noise: Overload: Frequency response: Filters:

1-1

A/D conversion: Sampling speed:

Amplifier Section

13 bits 1ms

Recording system: Paper speeds: Recording density:

Chart paper:

Auxiliary Input Section

DC input:

Display Section

Display:

Types of characters:

General

Safety features:

Power requirements:

Dimensions:

Weight:

Thermal writing with thermal print head

25 and 50mm/sec within ±3%

8 dots/mm in amplitude direction

1msec in time axis direction Roll paper 63mm wide x 30m long

Z-fold paper 63mm wide x 20m long,

75mm/fold

10mm/0.5V, unbalanced, input impedance

100kO min.

Liquid crystal, 40 characters (20 chars. x 2 lines), character configuration 5 x 7 dots Alphanumerics and symbols

Class I and internally-powered equip-

ment, Type CF (IEC 601-1)

115V AC, 50/60Hz; 19VA 230V AC, 50/60Hz; 19VA

Ni-MH rechageable battery 9.6V DC, 7W

Continuous operation time: Approx. 70

minutes at 20°C

Charging time: Within 3 hours

260N) x 18.2(D) x 6.05(H) cm

2.0kg (including the battery)

Operating Environmental Conditions

Temperature: 10 to 40°C

Humidity: 30 to 85% R.H. (no dew condensing)

Atmospheric pressure: 70 to 106kPa (700 to 1060mbar)

Transportation/Storage Environmental Conditions

Temperature: -10 to +50°C

Humidity: 10 to 90% R.H. (no dew condensation)

Atmospheric pressure: 70 to 106kPa (700 to 1060mbar)

1-2

3. Controls and Indicators

Top Panel

Paper Magazine

® Equipotenlialization Terminal-

\..

Left Panel

cgm

(2)

Power Connector

co-

-.-

Right Panel

-Ii

Display

®Operation Panel

}

WARNING Label

CAUTION Label

Bottom Panel

-t--t-1r--

Rechargeable Battery Case

1-3

Front Panel

Display:

Operation Panel:

@ Paper Magazine:

Left

and Right Panels

Signal Input Terminal: Inputs external signals. The recording

® Serial Port: ® Lead Connector:

(J) Power Connector:

® Main Power Switch:

Displays the prevailing recording mode, lead name, sensitivity and heart rate or

program. See the next page for details. Accommodates the chart paper.

sensitivity is 10mm/O.5V.

Inputs and outputs serial data from/to other instruments.

Connects to the lead cable. Connects to the power cord. Turns AC power on/off.

® Equipotentialization Terminal: Connects to the grounding conductor

common to another instrument, if con-

nected, via an optional grounding wire.

Rear Panel

Rechargeable Battery Case: Accommodates the rechargeable

battery.

Fuse Holder: Has the power fuse inserted.

1-4

Operation Panel

Mode

@ Program

(}) Sensitivity

. @Sex!

®Age

JtoIO.C

r.oc...... SClfsmvrTY

ILl

.Ct

VruKuDA D£"SIII

ern'

l:lCJ

......

-,'

® Lead Select

AUTO CARDINER

FCP -

2155

LEAD

.i:

®®

evCopy

E3BATTERY

S TAR T

OFF

RESET

1m V

( <P\

Battery On

Mode:

@ Program:

Sensitivity:

@Sex: ®Age:

® Lead Select:

Ci)

Copy:

® Start/Stop:

@1mV:

Battery Off/Charge

Reset

@1mV

® Start/Stop

Selects a recording mode from automatic, manual, arrhythmia analysis and autonomic nerve exami-

nation.

Selects the program mode.

Selects a recording sensitivity from AUTO, 1,

1/2,

1/4

and 2

cm/mV.

Selects male or female. Selects an age group from 0-2,3-11,12-18,19-29and

over 30 years old. Select a lead group. Note, however, that this key

is not effective for analysis and automatic record- ing modes in which lead selection is automatically made.

Copies an analysis or autonomic nerve examina- tion record. It is effective only when the data is available in the instrument. Note that starting the

next record or changing the recording mode erases

the data for copying.

Starts the instrument recording. In the manual or arrhythmia analysis mode, a second press of the key stops the instrument from recording. In other modes, the instrument stops recording automat- ically.

Applies 1mV calibration waveform in the manual mode.

1-5

@ Reset: Keeps resetting the circuit while held down. @ Battery Off/Charge: Turnsthe power off in battery operation. In AC oper-

ation, a press of the key places the instrument in charge mode.

@ Battery On:

Turns the power on in battery operation. A press of the key during battery charge cancels charge mode and calls up the same initial display as upon turning the AC power on.

1-6

CHAPTER

Circuit Description

1. Introduction 2-1

2. Floating Input Circuit 2-3

2.1 Buffer Amplifier 2-4

2.2 Middle Amplifier : 2-5

2.3 A/D Converter 2-6

2.4 Amplifier Control and Interface 2-7

3. Peripheral A/D Converter Circuit 2-S

4. Clock

5. Serial Port 2-9

6. Motor Control Circuit 2-10

7. Sensor Circuit 2-11 S. CPU·GA Circuit 2-11

9. LCD Control Circuit 2-12

10. Thermal Print Head Control Circuit. 2-12

11. Power Supply Circuit with Charging Circuit 2-13

11.1 Outline of the System 2-13

11.2 Rectifier/Smoothing and On/Off Control Circuits 2-13

Backup Memory 2-S

11.2.1 AC Operation 2-13

11.2.2 On/Off Control Circuit 2-13

11.2.3+5V and+5VA Generator 2-14

11.2.4 -5VA Generator 2-14

11.2.5+SV Generator 2-15

11.2.6+24V Generator 2-15

11.2.7 Isolated Power Circuit.. 2-16

11.2.S Charging Circuit 2-17

1. Introduction

The FCP-2155 is composed of the following circuits:

(1) Main Board PCB-6430

• Floating input circuit

• Motor control circuit

• Sensor circuit

• Reset circuit

• CPU circuit

• LCD control circuit

• Thermal print head control circuit

• Memory backup circuit

• Power supply ciruit

• Charging circuit (2) Sensor Board PCB-6239 (3) AC Inlet Board PCB-6410

ECG signals input from the lead connector are amplified in the float-

ing input circuit. The amplified signals are converted into digital signals.

The digital signals are digitally filtered then transferred to the thermal print

head control circuit to be recorded on the chart paper.

The LCD screen displays the heart rate detected with a software

technic, lead-off status, if any, filter onloff status, etc.

The power supply circuit supplies power to circuits, while the charg-

ing circuit charges the Ni-MH battery. The charge status is displayed on

the LCD screen.

2-1

Block Diagram

PCB-M30

AC Power Source

.0 _~_. _.

o _. • _ • • _. _. • _ .. _ .. _. _ .. ',

. .

r=r=>;

-_-_-,

5VII';;-

1 '.

I I

AC Inlel

--1-'

Board

--T'

+24V

Power Supply

Floating Input

Circuit

! !

PCB-6410

Circuit

+12VN

--4

+5V

-7-

L,__________

" I

Charging

i-.

Circuit

, ,

Ni·MH

Battery

Peripheral

Clock

Backup

Memory

I I

Serial

Port

1 1

'._0_,

1 1

-D

DC Motur

Thermal Print Head

. !

1 1

Motor Control

'. I

, ,

Key Panel

, , ,

Reset Circuit

G.A.

---

CPU ROM DRAM

• I

• __ o • .. ._o _

,_._-_._-_-

-.-.-.-.-.~

• I

Sensor Board

PCB-6239

LCD

'_._-_._-_-_-_._._-_._-_-_

2-2

2. Floating Input Circuit

The floating input circuit is composed of the following:

(1)Buffer amplifier (2)Middle amplifier (3)AID converter (4)Amplifier control and CPU interface

CS C6

Buller Amplifier

L F

C2 C3 C(

CS C6

S T 0

L F

C2 C3

.. .

Middle

. Amplifier

I :.//

-IT

I •

Y2 V3

:::E

AOC

I'--

STD

E C G

AMP

CAL

'..__

......_

'.__

.'._ .'._

'._

'.__

)(

:::E

CONTROL

Block Diagram of Floating Input Circuit

[B]~

.fi

---E-

2-3

2.1 Buffer Amplifier

The buffer amplifier converts the input signals into high-impedance signals and the output signals into low-impedance signals. Each input has 50kO and 10kO resistors mounted in series, thereby suppressing a

patient measurement current at single fault to less than 50~. Dual tran- sistors Q10 to Q18 are mounted as limiters to protect the circuit against excess input.

The RF drive circuit feeds back the Wilson's center signal to the right

foot of patient for improved

Each input is put in a minus potential by a 500 resistor. The reason

is that a lead-off status can be detected by pulling the input potential at the time of electrode disconnection into that minus potential.

The output of each buffer amplifier is connected to the lead-off detec-

tion circuit to let it check for any possible disconnection of electrode.

CI ". __ ~

'U...

...

....

(I,.

2-4

2.2 Middle Amplifier

The middle amplifier has eight channels for I, II, V1, V2, V3, V4, V5

and V6.

Differential amplifiers for RA-LA and RA-LF commonly use the amplifier for RA. Differential amplifiers for the midpoint of limb and C1 to C6 commonly use the amplifier for the midpoint of limb.

The differential amplifier section provides a gain of 7.5 times and the non-inversion amplifier section provides a gain of 20 times, thereby offer- ing a total gain of 150 times.

The time constant is set at 3.5 seconds by 1Wcapacitor and 3.5MO resistor. Under a reset condition, 1Wcapacitor and 20kO resistor make the time constant 0.02 seconds.

The output of each differential amplifier is connected to the lead-off

detection circuit to let it check for disconnection of electrode.

l!U ,....T

&.:11 UI, C,I Uti

,...:1

-.J

u(./

t... "

IJU

.....

....

,.,.

2-5

2.3 AID Converter

The multiplexor (IC35, 36, 41) sequentially selects analog signals of middle amplifier and lead-off detection to let the them to digital signals. It takes 1211Sto convert signals of one channel.

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.It

,.. U

...~.......-~~~~~".r'r'l'

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converter (lC39)convert

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t--"VV'-f

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1'"

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t-l...

r:;:;

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u..

......

•

Signals are input in the

Lead for lead-off detection is switched every 1ms.

V1 to Lead Off V1 to Lead Off

1ms

,.,

AJD

converter in the following order.

2-6

2.4 Amplifier Control and Interface

IC38 controls signals such as STD, RESET, and CAL transferred from

the CPU. The

AJD

converter transfers the data to the CPU via

1C38

in the

following order:

STXIV1

I " I

I OP IL.OFF

SRX

L- ~ ~

Control data

1ms

"".

II:,.

.....

TUn

....

TUn

1Un

"".

""'"

...,..

......

ont

o.;"ij,- - ... __

2-7

3. Peripheral AID Converter Circuit

IC13of peripheral AiD converter circuit converts analog signals around

the CPU, such as lithium battery voltage, Ni-MH battery voltage, thermal

print head temperature, and DC input, into digital signals with a resolu-

tion of 10 bits.

The DC input accepts signals of up to ±3.2V {±6.4cm}. AiD converted data are transferred to the CPU in serial communication. This peripheral AiD converter circuit also detects abnormal temper-

ature of thermal print head.

::~

,,_

.•.

r..:

.~±

[

La?

J/~

...

r-V

;tf ~ ._

~.-(--Q~.

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co.

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...

;:;

;::0::

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::: i

,,_

....

=::...

•

-;;.

'-"

-_.

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4. Clock & Backup Memory

IC4 has a clock, backup memory, and power switching circuit built in. Clock and backup memory data are transferred to the CPU in serial

communication.

',n

....

('~I

,,_

'-C./~

'..;;.It-=::

'-'

r--

......

.,"

...

<:»

r::

2-8

5. Serial Port

The serial controller is in the GA

RS232G level by IG5 and IG6.

The connector J1 can supply +5V power. But do not take an output

of over 500mA from the connector.

Caution: Take care of the serial port. It is not floating.

....

H"'"

novr

....

(1GB)

and the data from it are made

It..

UD4T4

LJ'

•

IOU

...

'"'

.....

....

LJ'

IOU'

2-9

6. Motor Control Circuit

The recorder driving motor is a DC motor equipped with a photo sensor for speed detection. The signal detected by the photo sensor is compared in phase with the reference frequency by the PLL controllC (IC22) to pro-

vide a motor control signal at pin transferred to the PWM control circuit of IC27 via the integrator circuit (R27, R209, C25) so that a proper motor drive voltage is supplied.

of IC22. The motor control signal is

t5V

Pin 14 of IC22

Pin 3 01lC22

Pin 13 of IC22

I I I'

I I I I

· .

JLU,~__,

...

~""

· .

tSV

t5V

+3. 2V

2. 2V

...

2-10

7. Sensor Circuit

The sensor circuit is provided to detect paper magazine open condi-

tion, paper end, and paper mark.

8. CPU·GA Circuit

The CPU·GA circuit is composed of a reset circuit, CPU, ROM, DRAM,

and GA.

(1) Reset Circuit

....

•

....

L~~

'ucr

• ....h.U..

...

..,.'"

"'"

•

...

I:..'

(2) CPU, ROM, DRAM, GA

12.5MHz TMP68HCOOOis used for the CPU (IC9), which controls the overall system via GA (ICB).The ROM (IC3) has a capacity of 4 Mbits (512 Kbytes). The DRAM (IC15) has a capacity of 4 Mbits (512 Kbytes).

In addition to various kinds of control, the GA inputs key operation

_•• ~rz ..,

0.:;./

" 1

..'¢' :,'"

'Ct,

,,7

1':'-

>:;

signals.

2-11

9. LCD Control Circuit

Since the LCD (NDM202AOO)has a controller built in, it is interfaced

directly with the CPU.

VO for contrast adjustment is set at a fixed voltage.

10. Thermal Print Head Control Circuit

The thermal print head control circuit is built in the GA (IC8) controls the print head for recording waveforms and alphanumerics, as well as controlling strobe and heating temperatures.

Data transfer

Waveform data are written in the register in the gate array every 1ms then transferred to the thermal print head. Alphanumeric data are trans- ferred to the thermal print head via the gate array.

Strobe control

The thermal print head heating degree is controlled by changing the base temperature or the pulsewidth of strobe according to a chart speed.

Heat control

Previous dot heating information is stored in the heat control memory and based on the information heating temperature is controlled to an optimum printout condition.

Print head protection

An overheat of thermal print head or magazine open condition forcibly shut off the +24V supply.

2-12

11. Power Supply Circuit with Charging Circuit

11.1Outline of the System

Using the AC power through the transformer or the OC power from the NI-MH battery, the power supply circuit makes and supplies neces- sary regulated powers. The power supply circuit involves a circuit to charge

the Ni-MH battery.

AC Power

OC Power

Transformer

Battery

Rectifier

ON/OFF

J--

-1

Chargingcircuit

Block Diagram of Power Supply Circuit

control

circuit

J-~

+12V

Regulatedpowers

+8V +5V

±5VA

±5VF, B

+24V

rJ'J

:=::

:::J

i:3

Cl.

rJ'J

a:::

11.2 Rectifier/Smoothing and On/Off Control Circuits

11.2.1 AC Operation The AC power transformed in voltage by the transformer is rectified

through 09, 011, 015, and 016 and smoothed by C1 and C2. These low

VF Schottky diodes 09, 011, 015, and 016 form a bridge circuit to reduce

lowering of the voltage and features less heat generation.

11.2.2 OnlOff Control Circuit

In battery operation, a press of the Battery ON key turns the FEr switch

025 on, thereby letting the current flow to 03 and the base of 03 be driven.

Thus, 05 is kept on and the power is supplied to the equipment if the Bat-

tery On key is detached.

The battery voltage is detected via 022. If it lowers to approximately

7.9V,the gate array generates a power-off signal to turn 021 on and can-

cel the bias voltage of 03, thereby turning 025 off. Since power supply to the equipment stops at that time, the equipment is turned off.

Similarly, when the Battery Off key is pressed, the bias voltage of 03

is cancelled, thereby turning the equipment off. In AC operation, 021 is on and the base of 03 cannot be driven, thereby making it impossible to keep 024 in ON status and disabling battery operation.

2-13

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11.1

20K

.. 1147

lOt(

IISl

10K

11.2.3 +5V and +5VA Generator

IC7(FDD1203M) is a DCIDC converter having a capacitor at the input

and output to make the regulated +5V from the unregulated 12VN. The output voltage is internally fixed at +5V.

The 5V power supplied from le7 provides +5V and 5VA for digital

and analog systems. The capacitor at the output is an organic semicon- ductor capacitor which features good low-temperature characteristic, less

leakage current and superior high-frequency characteristic.

11.2.4 -5VA Generator IC43 is a CMOS inversion type switching regulator. Its output voltage

is internally fixed.

inverts the input +5V to output - 5V. The capacitor

at the output is an organic semiconductor capacitor.

(OS COH)

llu lSV

t--:-:'~__"'

12"

10V

(OS COH)

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-SVA

10_

laO"

10V

(OS 'OH)

2-14

+ 106 hidden pages