Diodes AP2008 - Manual (Page 5)

AP2008
PWM BUCK CONTROLLER
AP2008 Rev. 2 5 of 8 FEBRUARY 2009
www.diodes.com © Diodes Incorporated
Electrical Characteristics
(Continued) (T
A
=25ºC, V
CC
=6V, f=200 Khz)
Output section
Symbol Parameter Conditions Min Typ. Max Unit
I
LEAK
Leakage current V
O
= 20V 10 µA
I
DRV
Sink current V
IN
= 12V 200 mA
Source current V
IN
= 12V 200 mA
V
SAT
Output saturation voltage I
O
= 10 mA 1.0 1.5 V
I
SC
Short-circuit output current V
O
= 6V 120 mA
PWM comparator
Symbol Parameter Conditions Min Typ. Max Unit
V
T0 Input threshold voltage at f = 10 KHz
(COMP)
CT=6800pF 0.6 0.7 V
V
T100
Maximum duty cycle 1.2 1.3 V
Total device
Symbol Parameter Conditions Min Typ. Max Unit
I
CCA
Average supply current C
T
= 270pF 6 10 mA
Soft Start
Symbol Parameter Conditions Min Typ. Max Unit
V
SS
Soft-start Voltage 2.3 V
I
SS
Constant Charge Current 20 µA
Typical Application Circuit
L1
10uH
R1
R2
C3
470uF
Output
Step-Down DC/DC converter
C2
10nF
(Optional)
Vcc = 12V
P mos
Q1
1 2 3
8 7 6 5
4
OUT FB VCC COMP
GND
SCP
SS CT
C6 220nF
C5 50nF
C4 270pF
1K
4K
C1
470uF
5A
R3 30K
C4
50nF
(Optional)
1V/5A