Samsung 2232BW - SyncMaster - 22" LCD Monitor, Руководство по обучению

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2. Circuit Description (IP Board - Dimming)
Ther e ar e t hr ee met hods . The Cur r ent Cont r ol met hod adj us t s t he s i ze of t he cur r ent
ent er i ng t he l amp. The PWM met hod t ur ns t he l amp on and of f accor di ng t o a s peci f i c
f r equency. The Compl ex met hod mi xes t hos e t wo met hods .
Cur r ent Cont r ol ( Anal og Di mmi ng)
- Di mmi ng i s pos s i bl e wi t h compar at i vel y no ef f ect on t he panel .
- A mi ni mum cur r ent i s r equi r ed wi t h whi ch no par t i al l i ght ni ng occur s i n
t he l amp at t he mi ni mum br i ght nes s .
- Low di mmi ng r at i o ( Appr ox. 2: 1)
- Becaus e t he i nver t er i s opt i mi zed t o t he maxi mum br i ght nes s , t he
ef f i ci ency i s degr aded i n t he di mmi ng s t at e.
PWM Cont r ol ( Bur s t Di mmi ng) – The Pi ccol o model us es PWM f ul l y f r om OSD 0 t o 100.
- Di mmi ng i s achi eved by t ur ni ng t he l amp on and of f at a f r equency of appr ox.
300 Hz t o 1 kHz.
- Tur ni ng a l ar ge capaci t y of cur r ent on and of f at a s peci f i c cycl e caus es
gr ound i ns t abi l i t y and noi s e t o t he panel , whi ch r es ul t s i n wat er f al l s on t he
s cr een.
- Becaus e i t oper at es at t he maxi mum br i ght nes s when t he l amp i s on, t he
ef f i ci ency i s hi gh. I t r es ol ves t he pr obl em of par t i al l i ght ni ng at mi ni mum
br i ght nes s , t hus , di s pl ays a hi gh di mmi ng r at i o ( appr ox. 5: 1) .
Compl ex Cont r ol
-
Removes t he pos s i bi l i t y t hat wat er f al l s can occur by us i ng t he anal og met hod at
t he ear l y s t age of di mmi ng.
-
Hei ght ens t he di mmi ng r at i o by us i ng t he PWM met hod at t he l at er s t age of
di mmi ng.