Diodes ZXSC310 - Manual (Page 11)

Output Power Calculation
By making the above assumptions for inductance and
peak current the output power can be determined by:
Note:V OUT =output voltage + Schottky rectifier voltage
drop.
Where
T
OFF
≅1.7us (internally set by ZXSC310)
and
and
Where
Operating frequency can be derived by:
Capacitor selection
For pulsed operation, as in the maximum battery life
solution, no capacitors are required at the output to the
LED. For rectified operation, as in the maximum
brightness solution, a small value ceramic capacitor is
required, typically 2.2uF.
Generally an input capacitor is not required, but a small
ceramic capacitor may be added to aid EMC, typically
470nF to 1uF.
(notes)
ZXSC310
ISSUE 3 - SEPTEMBER 2007
11 S E M I C O N D U C T O R S
( )
I I
V V T
L
MIN PK
OUT IN OFF = −
− ×
( ) F
T T ON OFF
=
+
1
I
I I
AV
PK MIN =
+
2
( )
T
T V V
V
ON
OFF OUT IN
IN
=
−
P V V I
T
T T
OUT OUT IN AV
OFF
ON OFF
= − Ч Ч
+
( )