User Manual

Preliminary Datasheet
380kHz, 2A Asynchronous DC-DC Buck Converter AP3201A
Mar. 2011 Rev. 1. 0 BCD Semiconductor Manufacturing Limited
5
Electrical Characteristics
V
IN
=V
EN
=12V, V
OUT
=3.3V, unless otherwise specified. Specification with standard typeface are for T
A
=25
ºC, and those in boldface type apply over the full operating temperature range (T
A
=-40 ºC to 85 ºC)
Parameter Symbol Conditions Min Typ Max Unit
Input Voltage V
IN
4.75 18 V
Quiescent Current I
Q
V
FB
=1.0V, V
EN
=2V 1.0 1.5 mA
Shutdown Supply Current I
SHDN
V
EN
=0V 1 10
µA
Feedback Voltage V
FB
0.902 0.920 0.938
V
Feedback Over Voltage
Threshold
V
FBOV
1.1 V
Feedback SCP Voltage Threshold V
FBSCP
0.6 V
Feedback Bias Current I
FB
V
FB
=1V -0.1 0.1
µA
High-side Switch On-resistance (Note 2) R
DSONH
I
SW
=0.5A
0.22
Ω
Low-side Switch On-resistance (Note 2) R
DSONL
I
SW
=0.05A
10
Ω
High-side Switch Leakage Current I
LEAKH
V
IN
=18V, V
EN
=0V
V
SW
=0V
0.1 10
µA
High-side Switch Current Limit I
LIMH
2.8 3.8 A
Low-side Switch Current Limit I
LIML
From drain to source 0.15 A
V
ENH
1.5
EN Pin Threshold
V
ENL
0.5
V
EN Pull-up Current I
EN-PH
V
EN
=0V 1.0
µA
Input UVLO Threshold V
UVLO
V
IN
Rising 3.5 3.9 4.4 V
Input UVLO Hysteresis V
HYS
0.3 V
Oscillator Frequency F
OSC1
380 kHz
Short Circuit Oscillator
Frequency
F
OSC2
90 kHz
Maximum Duty Cycle D
MAX
V
FB
=0.8V 90 %
Minimum Duty Cycle D
MIN
V
FB
=1.0V 0 %
Error Amplifier Voltage Gain (Note 3) A
EA
400 V/V
Error Amplifier Transconductance G
EA
700
µA/V
COMP to Current Sense
Transconductance
G
CS
2.4 A/V
Thermal Shutdown (Note 3) T
OTSD
160 ºC
Thermal Shutdown Hysteresis (Note 3) T
HYS
30 ºC
Soft-start Time (Note 3) t
SS
I
OUT
=500mA
C
SS
=0.1µF
10 ms
Soft-start Current I
SS
6
µA