HT16565
HT16565 is 24 Hour System VFD Digital Clock manufactured by Holtek Semiconductor.
Features
- VFD display 24 hour clock function
- 4.194304MHz crystal oscillation
- Zero adjust function
- Integrated voltage regulator permits wide 4V to 16V operating voltage range
- Four level contrast control function
- 44-pin QFP package
General Description
The HT16565 provides direct drive to VFD panels to implement a 24 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 device also contains a host of other features
. These include 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.
Block Diagram
O S C O O s c illa to r O S C I V T E S T 3 T E S T 2 T E S T 1 V
C M O S F r e q u e n c y D iv id e r s 1 H z
6 4 H z 1 H z
T e s t A d ju s tm e n t
S e c o n d C o u n te r a 1
D D b 1 c 1 T im e A d ju s tm e n t
A /C S E Z A M S H S
M in u te C o u n te r
D e c o d e r S e g m e n t
D r iv e r [P C H
H o u r C o u n te r
D e c o d e r S e g m e n t
O p e n D r a in ] g 3 b 4 c 4 a 4 , d 4
V C O N T 2 C O N T 1 D IM
C o n tra s t A d ju s tm e n t e 4 , g 4
V T E S T 4 V S 1 2 2 4
Rev. 1.00
February 7, 2007
Data Sheet.in
Pin Assignment
T T T a 4 , d H M E S T E S T N E S T E S T Z e 4 , g c 4 g 3 e 3 d 3 c 3
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 2 1
T c 1 d 1 e 1 g 1 c 2 e 2 g 2 c 3 d 3 g 3 e 3 C S S A 1 4 3 2 4
3 3 3 2 3 1 3 0 4 4 4 3 4 2 4 1 4 0 3 9 3 8 3 7 3 6 3 5 3...