Diodes AP5100 User Manual
Ap5100, Description, Pin assignments
AP5100
1.2A STEP-DOWN CONVERTER with 1.4MHz SWITCHING
FREQUENCY
AP5100
Document number: DS32130 Rev. 3 - 2
1 of 12
April 2012
© Diodes Incorporated
Description
The AP5100 is a current mode step-down converter with a
built-in power MOSFET to enable smallest solution size
power conversion.
With the low series resistance power switch it enables a
constant output current of up to 1.2A over a wide input supply
range. The load and line regulation has excellent response
time over the operating input voltage and temperature range.
The AP5100 is self protected, through a cycle-by-cycle
current limiting algorithm and an on chip thermal protection.
The AP5100 will provide the voltage conversion with a low
count of widely available standard external components.
The AP5100 is available in SOT26 package.
Pin Assignments
1
2
3
74
6
EN
GND
IN
FB
SOT26
5
BST
( Top View )
SW
Features
•
V
IN
4.75V to 24V
•
Load current of up to 1.2A
• Internal
Power
MOSFET
•
Stable with Low ESR Ceramic Output Capacitors
•
Up to 90% Efficiency
•
0.1µA Shutdown Mode
• Fixed
1.4MHz
Frequency
• Thermal
Shutdown
•
Cycle-by-Cycle Over Current Protection
•
Resistor divider adjustable Output: 0.81V to 15V
•
SOT26: Available in “Green” Molding Compound
(No Br, Sb)
•
Lead Free Finish/RoHS Compliant (Note 1)
Applications
• Distributed Power Systems
• Battery
Charger
• Pre-Regulator for Linear Regulators
• WLED
Drivers
Notes: 1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions applied. Please visit our website at
Typical Application Circuit
BST
SW
FB
IN
EN
C2
AP5100
R1
R2
D1
GND
V
IN
C3
.L1
C1
ON
OFF
C6
5
4
1
6
3
V
OUT
Figure 2. Typical Application Circuit
0.6
0.8
1.0
1.2
0
0.2
0.4
LOAD CURRENT (A)
Fig. 1 Efficiency vs. Load Current
E
FFI
C
IE
N
C
Y
(%)
100
90
80
70
60
50
40
V = 12V
L = 3.3µH
IN
V
= 5V
OUT
V
= 3.3V
OUT