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1. General ............................................................................................... 1

2. Circuit description ............................................................................... 1

3. Circuit diagram.................................................................................... 5

4. PWB layout ......................................................................................... 7

CONTENTS

Parts marked with "

" are important for maintaining the safety of the set. Be sure to replace these parts with specified

ones for maintaining the safety and performance of the set.

This document has been published to be used 
for after sales service only.
The contents are subject to change without notice.

The UP-I16DP is a remote display option for the POS.

·

7-segment display:
Font:

Positions:

11 positions

Character size: 12.0(H) x 6.0(W) mm

·

Dot display:
Pattern:

Positions:

16 positions

1) When the pin-14 output level of the comparator IC4 is at high

(open), the positive voltage of the pin-9 becomes about +2.7V by
the voltage division with the positive side divider resistors (parallel
connection R52, R42, R49) and R50. At this point, the negative
voltage on the pin-8 is charged from R51 to C29 and begins to
rise.

2) When the negative side voltage turned higher than the positive

side, the output is then inverted to low level.

3) When the pin-14 output of the comparator IC4 has turned low, the

pin-9 positive voltage turns to about 2.3V by the voltage division
with R42 turned to the negative side voltage dividing resistor and
the parallel inserted resistors R50 and R42, and R49 voltage divi-
sion. Then, for the negative voltage on the pin-8, the charge in
C29 is discharged through R51.

4) The output turns high when the negative side voltage went lower

than the positive side voltage.

Above steps 1) through 4) are repeated to oscillator.

1) The converter transformer is driven with the signal from the oscil-

lation circuit in 2-1-1. In case the feedback signal and the overcur-
rent are not detected, it will be driven by this circuit.

These signals are used for input to the comparator IC4, pin-11 (+) line
of the feedback circuit.

–26V feedback signal

Overcurrent monitor signal (reter to "2-1-4")

1) The feedback from –26V line is sent to the pin-11 of IC4 as a

voltage divided by R46, R43 and R55. The comparator IC4 com-
pares the signal from the pin-11 with the comparator IC4 pin-10
signal of the oscillation circuit to control the feedback.

2) When the level on the pin-10 goes above that of the pin-4 at a

rising of the comparator IC4 pin-10 signal (Q1 turns on when the
comparator IC4 of the basic drive circuit turned off), the compara-
tor IC4 output turns on and Q1 turned off to stop driving the
converter transformer.

5.60

1.19

0.85

1.33

0.99

9.00

( Unit in mm)

R42

51k

9
8

13

IC4C
BA10339

R50 10KF

R51

100K

C29
330P

R52
1.5K

R49

10KF

VCC
(+5V)

VCC
(+5V)

5V

0V

2.7V

2.3V

14Pin

9Pin

8Pin

2.7V

2.3V

From oscillation circuit

5V

5

4

3

2

12

IC4B
BA10339

5V

R4
31K

Q1
C3144

A

C35

0.1µ

R43
13KF

R46
10KF

VCC

VCC

 11

 10

13

3

12

IC4D
BA10339

R55
2KF

C36
0.015µF

-26.25V

A

B

From pin-8

of IC4C

Comparator IC4

Comparator IC4

Comparator IC4

10pin (-)

11pin (+)

pin-14 output

pin-13 output

2.7V

2.3V

2.5V

High

Low

Low

High

ON

OFF

TR1 output

>>>>> USE FONT <<<<<

Helvetica/ Helvetica-Condensed/ Century-Schoolbook/ Symbol & OriginalFonts: (RingWorld2/RingFont2/Pa

Symbol/PartsCod)

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

If the level of the pin-11 signal was higher than the level of the
pin-10 (–26V being shallow), the drive time prolong. If the level of
the pin-11 signal was lower than the level of the pin-10 (–26V
being deep), the drive time shortens.

1) The pin-6 of the comparator IC4 is the overcurrent monitor input.

2) If the Q1 driving current increased and the voltage across R48

becomes above 0.6V, the comparator IC4 output turns on and its
level goes low and the voltage at 

B

 turn low.So, Q1 turns off by

the feedback circuit.

The CKDC9 is a 4-bit microcomputer developed for the POS and
provides functions to control the real-time clock, keys, and displays.
The basic functions of the CKDC9 are shown below.

Keys:

The CKDC9 is capable of controlling a maximum of 256
momentary keys. (Sharp 2-key rollover control)
Simultaneous scanning of key and switch
(When a key is scanned, the state of a mode and clerk
switch is also buffered. The host can scan the state of
switch together with the key entry data at the same time
the key is scanned.)

Switches:

Mode switch with 14 positions maximum
8-bit clerk (cashier) switch2-bit feed switch
1-bit receipt on/off switch
1-bit option switch
4-bit general-purpose switch (1-bit is used for keyboard
select)

Displays:

16-column dot display
12-column 7-segment display (column digit selectable)
All column blink controlled for the dot and 7-segment dis-
play decimal point and indicators
Programmable patterns for 7-segment display:
Four patterns
Internal driver for 7-segment display

Buzzer:

Single tone control

Clock:

Year, month, day of month, day of week, hour, minute,
second

Alarm:

Hour, minute

Interrupt request (event control):

Detection of key input, switch position change, alarm is-
sue, and counter overflow

VCC

VCC

R41
6.2k

R44
4.3k

  7

  6

1

3

12

IC4A
BA10339

R54
15k

R48
1W/0.33

  1

  4

T1

Q1
2SC3144

A

B

About

0.6V

NOTE 3:

Pull-up/down in the table indicates that the lines con-
cerned require external pull-up/down resistance.

No.

NAME

DESCRIPTION

1

+20V

—

2

+20V

—

3

/RESA

Inverted signal of RESA

4

RESA

Reset signal (Not battery back-uped)

5

SCK2A

Shift clock

6

/HTS2A

Data (Host to Sattellite)

7

/STH2A

Data (Sattellite to Host)

8

SHEN2

Shift enable

9

GND

—

10

GND

—

CKDC9 directly drives the 7-segment display.

The display tube employs a grid blanking dynamic drive and operates
in the following timing.

M66004FP receives command from CKDC9, and drives the dot dis-
play.

The display tube is driver in the following timing.

RESA

/RESA

SCK2A

/HTS2A

/STH2A

SHEN2A

POS Side

UP-I16DP

RESA
/RESA

SCK2A
/HTS2A

/STH2A

SHEN2A

POS Main PWB

+20V

RESA(RESET)

SHEN2A

SCK2A

-26V

-26V

+5V

CKDC9

G1-G11
SA-SG,DP,AP

7SEG-display

Gn-1

SA~SG
DP,AP

Gn

(n-1~11)

58µS

15~
24µS

976µS

976µS x 11

/CS

/DCS

SCK

/DSCK

SDATA

DS0

CKDC9

M66004FP

-26V

5V

DG0~DG15

D0~D34

DOT
DISPLAY

DGn-1

D0~D34

DGn

61µS

11~40µS

488µS

488µS x 16

<Dot display>