1

(LED) (SCR) - (, ) ' 4Z1PF 2014

(PIV, PRV)

(LED-Light-Emitting Diode)

(LED)

(LED)

(LED)

(LED)

(LED)

(LED)

(LED)Forward Current vs Forward Voltage

Red5, Ultra Red4, HE Red6, Orange7, Bright Red3,HE Green9, Yellow8

Relative Luminous Intensity vsForward Current

Ultra Red4, HE Red6, Orange7, Yellow8, HE Green9Red5, Bright Red3, Pure BlueC (SCR-Silicon-Controlled Rectifier)

(SCR)

(SCR)

(SCR)

TRIAC(TRIode for Alternating Current)

TRIAC(TRIode for Alternating Current)DIAC, or DiodeforAlternating Current

TRIAC(TRIode for Alternating Current)

DIAC, or DiodeforAlternating Current

-

-

-

- :

"

DC (RF) ()

Class A Class B Class C

,

- CE - CB - CC

vivo

?

, A

'

Class A

Push-pull

Class AB

ClassABCABConductionAngle360o180oLess than 90o180 to 360oPosition ofthe Q-pointCentre Point ofthe Load LineExactly on theX-axisBelow theX-axisIn between theX-axis and theCentre Load LineOverallEfficiencyPoor, 25 to 30%Better, 70 to 80%Higher than 80%Better than Abut less than B50 to 70%SignalDistortionNone if CorrectlyBiasedAt the X-axisCrossover PointLarge AmountsSmall Amounts ( )

( )

:

((Amplitude Distortion

(Frequency Distortion)

, Phase Distortion) )

- , .

( Crossover Distortion) CLASS-B . Class-AB ()

() -

() -

" /

" /

:

. A=1000. A -50%

1% - 50% A>>1 Af=1/B A