Pin Assignment

Note:

²*² col indicates a blink colon and col¢ indicates a continuous light colon.

Pin Description

Pin Name

I/O

Description

VCC

¾ High voltage power supply pin.

VDD

O

Built-in regulator voltage output pin for the device internal circuits.

VSS

¾ Ground pin.

DIM1

I

Illumination level control pins.

Internally connected to pull-down resistors.

DIM2

I

A/C

I

When the A/C pin is low, the internal circuits are reset.

The reset pulse width should be more than 2

ms.

Internally connected to a pull-high resistor.

ZA

I

Zero Adjustment pin.

Internally connected to a pull-high resistor.

HS

I

Hour Adjustment pin.

Internally connected to a pull-high resistor.

MS

I

Minute Adjustment pin.

Internally connected to a pull-high resistor.

BLANK

I

When low the Blank input pin will extinguish the display.

Internally connected to a pull-down resistor.

XT

O

Crystal oscillator pin

XT

I

TEST

I

IC test pin - should be left open or kept at a low level

64Hz

O

64Hz signal output pin for oscillation frequency adjustment

GR1

O

Grid output pins for 1/2 duty VFD

GR2

O

1a,3a ~

2b,4b,4c

O

Segment output pins for 1/2 duty VFD

HT16562

Rev. 1.20

2

December 17, 2010

1

2

3

4

5

6

7

8

9

1 0

1 1

1 2

1 3

1 4

1 5

1 7

1 8

1 9

2 0

3 0

2 9

2 8

2 7

2 6

2 5

2 4

2 3

2 2

2 1

1 6

H T 1 6 5 6 2

3 0 S S O P - A

G R 2

V C C

V D D

6 4 H z

T E S T

B L A N K

D I M 1

D I M 2

X T

X T

V S S

A / C

Z A

H S

M S

G R 1

2 a , 2 d

2 b , 4 b , 4 c

2 f

2 c , c o l *

2 c , c o l ' *

2 e

2 g

1 d , 3 d

1 e , 3 e

1 c , 3 c

1 g , 3 g

1 f , 3 f

1 b , 3 b

1 a , 3 a

1

2

3

4

5

6

7

8

9

1 0

1 1

1 2

1 3

1 4

1 5

1 7

1 8

1 9

2 0

3 0

2 9

2 8

2 7

2 6

2 5

2 4

2 3

2 2

2 1

1 6

H T 1 6 5 6 2 B

3 0 S S O P - B

G R 2

V C C

V D D

6 4 H z

T E S T

B L A N K

D I M 1

D I M 2

X T

X T

V S S

A / C

Z A

H S

M S

G R 1

2 a , 2 d

2 b , 4 b , 4 c

2 f

2 c , c o l *

2 c , c o l ' *

2 e

2 g

1 d , 3 d

1 e , 3 e

1 c , 3 c

1 g , 3 g

1 f , 3 f

1 b , 3 b

1 a , 3 a