mc44608 ON Semiconductor, mc44608 Datasheet - Page 9

• Manufacturer Part Number: mc44608
• Description: Few External Components Reliable And Flexible Smps Controller
• Manufacturer: ON Semiconductor

EQUATION 1
where: I
C
EQUATION 2
where: I
I
EQUATION 3
where: I
I
EQUATION 4
EQUATION 5
EQUATION 6
where: k
k
G
pin3
S/L
Vcc
Startup Phase Duration:
Switching Phase Duration:
Latched−off Phase Duration:
Burst Mode Duty Cycle:
is the current consumed by the Power Switch
= (UVLO1 − UVLO2)/(V
is the current drawn from pin3 adding a resistor
is the V
t start–up +
t
t
d
d
d
switch
latched*off
BM
BM
BM
stup
ccS
ccL
S/Stup
+
+
+
is the latched off phase consumption
is the no load circuit consumption in switching phase
is the startup current flowing through V
CC
+
t start*up ) t
C
1 )
= (V
Vcc
capacitor value
C
C
Vcc
stup
+
Vcc
k
(V
S Stup
C
− UVLO2)/(V
stup
Vcc
I
I
stup
(V stup * UVLO1)
ccS
(V stup * UVLO2)
switch
stup
* UVLO2)
t
I stup
switch
) I
I
ccL
(UVLO1 * UVLO2)
− UVLO1)
I
ccS
G
) t
I
) I
stup
stup
) I
pin3
latched*off
)
− UVLO1)
G
1
C
C
Vcc
)
Vcc
k
I
S L
CC
(V
ccS
I
(V
ccS
http://onsemi.com
stup
stup
pin
) I
) I
*UVLO1)
I
*UVLO1)
G
ccL
I
G
ccS
9
) I
) I
pin3
G
)
C
Vcc
I
(UVLO1*UVLO2)
ccL
) I
pin3