ht16561 & ht 16561b ( 44 qfp)

vfd digital clock

features:
vfd display 12 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 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 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.

盛群半導體(holtek)推出ht1656x系列數字頻率ic，該系列ic工作電壓范圍廣(4v～18v)、產品種類多樣、功能齊全、外接電路少，可利用汽車上的電源直接驅動熒光顯示面板( vfd)。 

        ht1656x系列ic客戶多款選擇，依面板驅動方式分為靜態顯示型ht16561、ht16565及1/2 duty動態掃瞄型ht16562、ht16566，依時間顯示方式分為12小時制(ht16561、ht16562)及24小時制(ht16565、ht16566)，12小時制又可帶有am/pm顯示功能(ht16561)。 

        全系列均4階段亮度調整、獨立的時/分校正及30分鐘舍入調整功能。外接電路少，只需外接4.194304mhz石英震蕩器及2顆振蕩電容即可起振，可直接驅動熒光顯示面板(vfd)。盛群的數字頻率ic亦可搭配使用boe 的 熒光顯示面板 vfd (vfd 20-0106n，hl-d265dw)。