Datasheet HT16561 Datasheet (Holtek Semiconductor Inc)

Features

·

VFD display 12 hour clock function

·

4.194304MHz crystal oscillation

·

Zero adjust function

General Description

The HT16561 provides direct drive to VFD panels to im
plement a 12 hour clock function. In addition to obtaining
its time base from a 4.194304MHz crystal oscillation
source and in having a wide operating voltage, the de
vice also contains a host of other features. These in

Block Diagram

HT16561

VFD Digital Clock

·

Integrated voltageregulator permitswide 4Vto 16V
operating voltage range

·

Four level contrast control function

·

44-pin QFP package

clude a choice of adjustment modes, including single

­push increment or 2Hz fast forward functions. Additional
features are provided in the form of Zero adjustment and
four levels of contrast control.

-

-

O S C O

O S C I

T E S T 3

T E S T 2

T E S T 1

A / C

C O N T 2

C O N T 1

D I M

C M O S

O s c i l l a t o r

V

D D

T e s t

A d j u s t m e n t

V

D D

V

D D

S E

Z A

M S

H S

V

D D

C o n t r a s t

A d j u s t m e n t

F r e q u e n c y D i v i d e r s

T i m e A d j u s t m e n t

1 H z

S e c o n d C o u n t e r

( 1 / 6 0 )

M i n u t e C o u n t e r

( 1 / 6 0 )

H o u r C o u n t e r

( 1 / 1 2 )

A M / P M

D e c o d e r

S e g m e n t

D r i v e r [ P C H O p e n D r a i n ]

D e c o d e r

S e g m e n t

6 4 H z

1 H z

a 1

b 1

c 1

g 3

b 4

c 4

A M

P M

V

D D

T E S T 4

Rev. 1.00 1 February 7, 2007

HT16561

Pin Assignment

T E S T 4

T E S T 1

P M

Z A

c 4

g 3

1
2

e 3
d 3

3

c 3

4
5

g 2
e 2

6
7

c 2
g 1

8

e 1

9

d 1

1 0

c 1

1 1

1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2

V D D

S E

D I M

6 4 H z

N C

H T 1 6 5 6 1

4 4 Q F P - A

N C

C O N T 1

T E S T 2

T E S T 3

M S

A M

H S

3 43 53 63 73 83 94 04 14 24 34 4

b 4

3 3
3 2

f 3
a 3

3 1

b 3

3 0

1 H z

2 9

f 2

2 8

a 2 , d 2

2 7

b 2

2 6

f 1

2 5

a 1

2 4

b 1

2 3

C O N T 2

A / C

O S C O

O S C I

V S S

c 4

P M

Z A
T E S T 1
T E S T 4

N C
T E S T 3
T E S T 2

M S

H S

A M

d 3

e 3

g 3

c 3

1
2
3
4
5
6
7
8
9
1 0
1 1

1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2

b 3

a 3

f 3

b 4

Pin Description

Pin Name I/O Description

VDD O High voltage power supply pin.

VSS

DIM I

CONT1 I

CONT2 I

A/C I

ZA I

HS I

MS I

SE I

OSCO O

OSCI I

TEST1, TEST2 I IC test pin - should be left open or kept at a low level

TEST3, TEST4 I IC test pin - should be left open or kept at a high level

64Hz O 64Hz signal output pin for oscillation frequency adjustment

a1, a3 ~ b2, b4, c4

1Hz

Ground pin.

¾

Illumination level control pins.
Internally connected to pull-down resistors.

Illumination level control pins.
Internally connected to pull-up resistors.

When the A/C pin is low, the internal circuits are reset.
The reset pulse width should be more than 2ms.
Internally connected to a pull-up resistor.

Zero adjustment pin.
Internally connected to a pull-down resistor.

Hour adjustment pin.
Internally connected to a pull-down resistor.

Minute adjustment pin.
Internally connected to a pull-down resistor.

Set enable pin.
Internally connected to a pull-up resistor.

Crystal oscillator pin

O Segment output pins for VFDAM, PM

e 2

g 2

H T 1 6 5 6 1 B
4 4 Q F P - B

f 2

1 H z

d 1

e 1

g 1

c 2

a 2 , d 2

c 1

3 43 53 63 73 83 94 04 14 24 34 4

6 4 H z

3 3
3 2

D I M
S E

3 1

V D D

3 0

C O N T 1

2 9

N C

2 8

C O N T 2

2 7

V S S

2 6

O S C I

2 5

O S C O

2 4

A / C

2 3

b 1

a 1

f 1

b 2

Rev. 1.00 2 February 7, 2007

Approximate Internal Connections

HT16561

Z A , M S , H S , D I M , C O N T 1 ,
T E S T 1 , T E S T 2

a 1 , a 3 ~ g 1 , g 3 ; a 2 , d 2 ~ g 2 ;
A M , P M

V D D

V S S

V D D

A / C , S E , C O N T 2 , T E S T 3 , T E S T 4

V D D

V S S

O S C I , O S C O

O S C O

( O s c i l l a t o r O u t p u t )

O S C I

( O s c i l l a t o r I n p u t )

V S S

6 4 H z

V D D

V S S

Absolute Maximum Ratings

Logic Supply Voltage .................VSS-0.3V to VSS+6.5V

High Input Voltage .....................V

Driver Output Voltage..........................V

-0.3V to VCC+0.3V

SS

-0.3V to V

SS

DD

Driver Output Current (Grid Driver) ......-7mA to +20mA

Driver Supply Voltage .................V

High Output Voltage ..................V

Driver Output Current (Segment Driver) -10mA to +2mA

Storage Temperature..........................-55°C to +150°C

Operating Temperature.........................-40°Cto+85°C

Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maximum Ratings² may

cause substantial damage to the device. Functional operation of this device at other conditions beyond those listed
in the specification is not implied and prolonged exposure to extreme conditions may affect device reliability.

-0.3V to VSS+20V

SS

-0.3V to VCC+0.3V

SS

Recommended Operating Conditions

Symbol Parameter Min. Typ. Max. Unit

V

f

OSC

t

OP

DD

Power Supply Voltage 4

Oscillation Frequency

Operating Temperature

-40 ¾

¾

¾

4.194304

16 V

¾

MHz

85

°C

Rev. 1.00 3 February 7, 2007

HT16561

D.C. Characteristics

Symbol Parameter

V

V

I

I

I

I

V

V

I

I

I

I

I

I

I

IH

IL

IH

IL1

IL2

IL3

OL

OH

OH1

OL1

OH2

OL2

OH3

OL3

DD

High Input Voltage 6V

Low Input Voltage 6V

Hi-level Input Current 6V

Low-level Input Current 6V

Low-level Output current 6V

Hi-level Output current 6V

Output Current 6V

Output Current 6V

Output Current 6V

Output Current 6V

Output Current 6V

Output Current 6V

Dynamic Current Consumption 6V

Test Conditions

V

DD

Conditions

¾

¾¾¾

for TEST1,TEST2,

V

I=VDD

ZA, MS, HS, DIM, CONT1

for TEST3, TEST4

V

I=Vss

VI=Vssfor A/C

VI=Vssfor SE, CONT2

for all pin

I

OL=VSS

I

V

for 64Hz pin

OH=VSS

=4.0V for 1Hz, a2, d2,

OH

a4, d4, e4, g4

=0V for 1Hz, a2, d2,

V

OL

a4, d4, e4, g4

=4.0V, Other segment

V

OH

output pins except above

OL=VSS

, Other segment

V
output pins except above

=5.5V for 64Hz pin

V

OH

=0.5V for 64Hz pin

V

OL

f

=4.194304MHz,

OSC

No load, C
C

OUT

C

=70W±5%

I

IN

=33pF±5%,

=39pF±5%,

VDD=6.0V, VSS=0V, Ta=-40°C~85°C

Min. Typ. Max. Unit

4.3

¾¾

V

1.0 V

30

¾

150

mA

-120 ¾-800 mA

-3 ¾-12 mA

-30 ¾-150 mA

5.9

¾¾

¾¾

0.1 V

V

¾¾-2000 mA

1

¾¾mA

¾¾-1000 mA

1

¾¾mA

¾¾-100 mA

100

¾¾

¾¾mA

2mA

Characteristics Curves

VDDvs IDDCharacteristics Curve

D D

D D

I

v s V

I

( m A )

D D

2 . 5

2 . 0

1 . 5

1 . 0

0 . 5

0

2 4 6 8 1 0 1 2 1 4 1 6 1 8

C h a r a c t e r i s t i c s C u r v e

Rev. 1.00 4 February 7, 2007

V

D D

Ta=25°C

( V )

Functional Description

VFD Display Driving

The device can directly drive VFD clock panels dynami
cally. The clock will be displayed in a 12-hour format with
the hours ranging from 1 to 12 and and minutes from 00
to 59. If the most significant numeral is zero then the dis
play will be extinguished.

·

Segment connections
A 7-segment display is shown below showing the illu
mination pattern for each numeral.

As the device is designed for clock applications, four
7-segment displays are required to display the correct
time output. The connections for the segments are
shown below, however it should be noted that the
fourth segment only requires two of its segments to be
driven.

A M

P M

b 4

c 4

d i g i t 4 d i g i t 3

A

F

B

G

7 - S e g m e n t s

E

C

D



a 3

f 3

e 3

1 H z

b 3

g 3

c 3

d 3

1 H z

a 2

f 2

g 2

e 2

d 2

d i g i t 2 d i g i t 1

a 1

f 1

b 2

c 2

b 1

g 1

e 1

c 1

d 1

Other Pin Functions

The external reset pin A/C is used to reset the internal

­circuit of the device. When this pin is pulled low the de
vice will be reset, when the pin is allowed to go high, via
its internal pull-high resistor, then the display will indi

-

cate a ²1:00² output.

In the open status, the SE pin is held to ²high² level by a

­pull-high resistor, enabling the inputs from MS, HS and

ZA pins. These inputs become invalid by setting this pin

to a ²low² level externally.

The 64Hz pin allows monitoring of the system frequency
to allow frequency adjustments to be executed. As the
name suggests, this output pin will continuously output
a frequency of 64Hz.

In the open status, the TEST1 and TEST2 pins are kept

at a ²0² level by pull-down resistors.

In the open status, the TEST3 and TEST4 pins are kept

at a ²1² level by pull-up resistors.

The Test pinfunction isas shownin the following table.

HT16561

-

-

TEST select function 1

Switch Pin Name

TEST1 TEST2 TEST3

0

(or Open)0(or Open)1(or Open)

F(Pulse)

1

1

F(Pulse)

F(Pulse)

1

F(Pulse)

F(Pulse)

1 0 Input pulses to the 64Hz system of the circuit.

0

(or Open)

1

(or Open)

1

(or Open)

0 Input pulses to the 64Hz system of the circuit.

0

Normal function

Input pulses to the 16.384KHz system of the circuit.

Input pulses to the 16.384KHz system of the circuit.

Input pulses for the minute and hour counters, which advances 1 count
with 1 pulse. No carry functions for hour and minute counters.

Operating mode

TEST select function 2

Switch Pin Name

TEST3 DIM CONT1 CONT2

0

F(Pulse)

**

The pulse widths of the all segment outputs are controlled
by the pulse width of the DIM signal

Operating mode

0 0 * * Sets all segment outputs to high impedance

Note: ²*² Indicates that the input level can be ²0² and ²1²

Rev. 1.00 5 February 7, 2007

HT16561

Three illumination level set pins, DIM, CONT1 and CONT2 are provided to give control over the display brightness
level, as shown in the following table.

Switch Pin Name

DIM CONT1 CONT2

0

(or Open)

1

1

11

* * 100% duty display

0

(or Open)1(or Open)

0

(or Open)

0 12.5% (1/8) duty display at 4096Hz

1

(or Open)

25% (1/4) duty display at 4096Hz

6.25% (1/16) duty display at 4096Hz

Note: ²1² high level, ²0² low level, ²*² don¢t care

Device Functions

·

Reset
Although the device is provided with an external reset
pin A/C, the device will in fact reset itself when power
is applied, eliminating the need for external reset com
ponents. The usual provision of an external capacitor
is not required as an internal reset capacitor is inte
grated within the device.

·

Chatter removal
The device contains circuits which are connected to
input pins HS, MS and ZA to remove chatter of less
than 31.25ms.

·

Oscillator
The basic time base frequency for this device is deter­mined by an external 4.194304MHz crystal. When an
external crystal along with two small external capaci­tors are connected to the two oscillator pins, the inter­nal oscillator circuit will ensure generation of the
correct time base signals. The oscillation frequency,
although determined by the external crystal fre
quency, will also be influenced by the external capaci
tors, the crystal inherent capacitance and the residual
capacitance of the external PCB tracks. To ensure ac
curate frequency generation, the crystal specification
should be taken into account and care taken to place
the external capacitors and crystal as close to the de
vice as possible.

Time Adjustment Operation

·

Hour/minute adjustment
Both the minutes and hour displays can be adjusted
separately or both together in a fast forward format.
The hour set pin, HS, and the minutes set pin, MS, are
used to make these adjustments. Both of these pins
are connected to internal pull-low resistors. Each time
one of these lines is pulled high, the respective hour or
minute value will increment by one, also if the line is
continuously held high then the respective value will
increment automatically at a rate of 2Hz. Both values
will increment together if both lines are pulled high si
multaneously. Note that no carry functions will be im
plemented when either the hour or minute value
overflows.

·

-

-

-

-

-

-

-

-

Operating mode

Zero adjustment
A zero adjust function is also included within the de
vice and is controlled by the ZA pin. This pin is con
nected to an internal pull low resistor. Pulling this line
high will reset both the internal minutes and seconds
value, however the way in which the display is reset
depends upon the present value of display. If the min
ute value is presently less than 30 the only the second
and minute values will be reset to zero and the hour
value remain unchanged. However if the minute value
is presently at a value of 30 or higher then when the
zero adjustment function is executed, a carry will be
implemented and the hour value will be increment by
one. The following table illustrates a few examples of
this operation.

Zero Adjust Examples

Present Time After Zero Adjust

Hr. Min. Sec. Hr. Min. Sec.

1 30 00 2 00 00

2 00 00 2 00 00

2 29 59 2 00 00

2 30 00 3 00 00

2 59 59 3 00 00

3 29 59 3 00 00

-

-

-

Rev. 1.00 6 February 7, 2007

Application Circuits

V

D D

T E S T 1

T E S T 2

H S

M S

Z A

D I M

C O N T 1

T E S T 3

T E S T 4

S E

A / C

C O N T 2

T E S T 1

T E S T 2

H S

M S

Z A

D I M

C O N T 1

T E S T 3

T E S T 4

S E

A / C

C O N T 2

V D D

V S S

HT16561

F +

1 H z
a 1

b 1
c 1
d 1
e 1
f 1
g 1
a 2 , d 2
b 2
c 2
e 2
f 2
g 2
a 3
b 3
c 3
d 3
e 3
f 3
g 3
b 4
c 4
A M
P M

C 1

J 1

E fV

F -

S t a t i c T y p e

C l o c k V F D

C C

1 H z

a 1
b 1
c 1
d 1
e 1

f 1

g 1

a 2 , d 2

b 2
c 2
e 2

f 2
g 2
a 3
b 3
c 3
d 3
e 3

f 3
g 3
b 4
c 4

A M
P M

O S C O

O S C I

6 4 H z

Y 1
4 . 1 9 4 3 0 4 M H z

C 2

1

C O N 1

Note: Capacitors C1 and C2 can adjust the frequency accuracy

Rev. 1.00 7 February 7, 2007

Package Information

44-pin QFP (10´10) Outline Dimensions

HT16561

C

D

2 3

1 11

Dimensions in mm

Symbol

3 3

3 4

A

B

4 4

Min. Nom. Max.

A13

B 9.9

C13

D 9.9

E

F

¾

¾

G 1.9

H

I

¾¾

¾

J 0.73

K 0.1

2 2

F

E

1 2

¾

¾

¾

¾

0.8

0.3

¾

0.1

¾

¾

H

G

K

a 0°¾7°

I

=

J

13.4

10.1

13.4

10.1

¾

¾

2.2

2.7

¾

0.93

0.2

Rev. 1.00 8 February 7, 2007

Preliminary

Holtek Semiconductor Inc. (Headquarters)

No.3, Creation Rd. II, Science Park, Hsinchu, Taiwan
Tel: [phone]
Fax: [phone]
http://www.holtek.com.tw

Holtek Semiconductor Inc. (Taipei Sales Office)

4F-2, No. 3-2, YuanQu St., Nankang Software Park, Taipei 115, Taiwan
Tel: [phone]
Fax: [phone]
Fax: [phone] (International sales hotline)

HT16561

Holtek Semiconductor Inc. (Shanghai Sales Office)

7th Floor, Building 2, No.889, Yi Shan Rd., Shanghai, China 200233
Tel: [phone]
Fax: [phone]
http://www.holtek.com.cn

Holtek Semiconductor Inc. (Shenzhen Sales Office)

5/F, Unit A, Productivity Building, Cross of Science M 3rd Road and Gaoxin M 2nd Road, Science Park, Nanshan District,
Shenzhen, China 518057
Tel: [phone]
Fax: [phone]

Holtek Semiconductor Inc. (Beijing Sales Office)

Suite 1721, Jinyu Tower, A129 West Xuan Wu Men Street, Xicheng District, Beijing, China 100031
Tel: [phone]
Fax: [phone]

Holtek Semiconductor Inc. (Chengdu Sales Office)

709, Building 3, Champagne Plaza, No.97 Dongda Street, Chengdu, Sichuan, China 610016
Tel: [phone]
Fax: [phone]

Holtek Semiconductor (USA), Inc. (North America Sales Office)

46729 Fremont Blvd., Fremont, CA 94538
Tel: [phone]
Fax: [phone]
http://www.holtek.com

Copyright Ó 2007 by HOLTEK SEMICONDUCTOR INC.

The information appearing in this Data Sheet is believed to be accurate at the time of publication. However, Holtek as
sumes no responsibility arising from the use of the specifications described. The applications mentioned herein are used
solely for the purpose of illustration and Holtek makes no warranty or representation that such applications will be suitable
without further modification, nor recommends the use of its products for application that may present a risk to human life
due to malfunction or otherwise. Holtek¢s products are not authorized for use as critical components in life support devices
or systems. Holtek reserves the right to alter its products without prior notification. For the most up-to-date information,
please visit our web site at http://www.holtek.com.tw.

-

Rev. 1.00 9 February 7, 2007