Samsung 2032BW Training Manual page 33

2. C ircuit Description (I P Board - Dimming)
Ther e ar e t hr ee m et hods . The
ent er i ng t he l am p. The
f r equency. The Com pl ex
Cur r ent Cont r ol ( Anal og Di m m i ng)
- Di m m i ng i s pos s i bl e wi t h com par at i vel y no ef f ect on t he panel .
- A m i ni m um 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 am p at t he m i ni m um br i ght nes s .
- Low di m m i ng r at i o ( Appr ox. 2: 1)
- Becaus e t he i nver t er i s opt i m i zed t o t he m axi m um br i ght nes s , t he
ef f i ci ency i s degr aded i n t he di m m i ng s t at e.
PW M Cont r ol ( Bur s t Di m m i ng) – The Pi ccol o m odel us es PW M f ul l y f r om OSD 0 t o 100.
- Di m m i ng i s achi eved by t ur ni ng t he l am p 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 m axi m um br i ght nes s when t he l am p 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 m i ni m um
br i ght nes s , t hus , di s pl ays a hi gh di m m i ng r at i o ( appr ox. 5: 1) .
Com pl ex Cont r ol
- Rem oves 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 m et hod at
t he ear l y s t age of di m m i ng.
- Hei ght ens t he di m m i ng r at i o by us i ng t he PW M m et hod at t he l at er s t age of
Cur r ent Cont r ol
PW M m et hod t ur ns t he l am p on and of f accor di ng t o a s peci f i c
m et hod m i xes t hos e t wo m et hods .
m et hod adj us t s t he s i ze of t he cur r ent