Owner manual

Preliminary Datasheet
2A, 4MHz High Efficiency Synchronous Buck Converter AP3408
Jan. 2013 Rev. 1. 1
BCD Semiconductor Manufacturing Limited
6
Electrical Characteristics (Continued)
V
IN
=V
DD
=V
PVDD
=3.3V, T
A
=25℃, unless otherwise specified.
Parameters Symbol Conditions Min Typ Max Unit
OSCILLATOR SECTION
RT Pin Voltage V
RT
0.8 V
Switching Frequency f
OSC
R
OSC
=330kΩ
0.8 1 1.2 MHz
ADJ Frequency 0.3 4 MHz
Maximum Duty Cycle D
MAX
V
FB
=0.75V 100 %
POWER SWITCH SECTION
Switch Current Limit I
LIMIT
V
FB
=0.75V 2.2 3.8 A
Internal P-FET On
Resistance
R
PDSON
I
SW
=500mA 0.11 0.16
Ω
Internal N-FET On
Resistance
R
NDSON
I
SW
=-500mA 0.11 0.17
Ω
SHDN/RT SECTION
Shutdown Threshold V
DD
-0.7 V
DD
-0.4 V
PGOOD SECTION
PGOOD Voltage Range ±12.5 ±15 %
PGOOD Pull Down
Resistance
120
Ω
TOTAL DEVICE
Output Current I
OUT
V
DD
=2.6 to 5.5V
V
OUT
=2.5V
2 A
Output Voltage Line
Regulation
LNR
V
DD
=2.7 to 5.5V
I
OUT
=100mA
0.4 %/V
Output Voltage Load
Regulation
LOD I
OUT
=0.01 to 2A ±0.2 %
Soft-start Time t
SS
I
OUT
＝10mA
1.5 ms
Thermal Shutdown
Temperature
T
OTSD
160 ºC
Thermal Shutdown
Temperature Hysteresis
T
HYS
20 ºC