Diodes AP3012 User Manual
Data Sheet
1.5MHz STEP-UP DC-DC CONVERTER AP3012
General Description
The AP3012 is a high power, constant frequency, current mode PWM, inductor based, step-up (boost) converter. The converter operates at high frequency
(1.5MHz) so that a small, low profile inductor can be
used.
The AP3012 has built-in overvoltage protection (OVP)
to allow the device goes into shutdown mode when the
output voltage exceeds the OVP threshold of 29V.
The AP3012 is available in standard SOT-23-5 package.
Features
· High Efficiency up to 81%
· Adjustable Output Voltage up to 29V
· Shutdown Current 1
· 1.5MHz Switching Frequency
· 36V 500mA Rugged Integrated Bipolar Switch
· Built-in Soft-start to Reduce Inrush Current Dur-
ing Start-up
· On-chip Overvoltage Protection
· Uses Low ESR Ceramic Output Capacitor
· Uses Small Inductor
µA Typical
Applications
· LCD/OLED Display Bias Supply
· White LED Driver for LCD Display Backlights
· Cellular Phones
SOT-23-5
Figure 1. Package Type of AP3012
May 2010 Rev. 1. 6 BCD Semiconductor Manufacturing Limited
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Data Sheet
1.5MHz STEP-UP DC-DC CONVERTER AP3012
Pin Configuration
K Package
(SOT-23-5)
1
SW
GND
FB
Figure 2. Pin Configuration of AP3012 (Top View)
2
34
5
V
IN
SHDN
Pin Description
Pin Number Pin Name Function
Switch Pin. Connect inductor/diode here. The output voltage can go up to 29V but should not
1SW
2 GND Ground Pin. Connect directly to local ground plane
3 FB Feedback Pin. Internally compares to 1.25V. Connect R1 and R2 resistor divider here. Calcu-
4 SHDN
5V
IN
exceed this limit. If the voltage on this pin is higher than the overvoltage protection (OVP)
threshold, the device can go into shutdown mode. It can be restarted by a low to high pulse on
the SHDN pin, or by a power on reset on the VIN supply
late the Output Voltage according to the formula: V
Shutdown Pin. Connect to 1.5V or higher to enable device (ON), 0.4V or lower to disable
device (OFF)
Input Supply Pin. Must be locally bypassed
=1.25V * (1+R1/R2)
OUT
May 2010 Rev. 1. 6 BCD Semiconductor Manufacturing Limited
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Data Sheet
1.5MHz STEP-UP DC-DC CONVERTER AP3012
Functional Block Diagram
1
Q1
0.2 Ω
SW
GND
2
FB
V
IN
SHDN
OVP
3
A1
5
V
REF
1.25V
SOFT
START
COMPARATOR
R
C
C
C
A2
DRIVER
R
Q
S
Σ
4
SHUTDOWN
RAMP
GENERATOR
1.5MHz
OSCILLATOR
Figure 3. Functional Block Diagram of AP3012
May 2010 Rev. 1. 6 BCD Semiconductor Manufacturing Limited
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Data Sheet
1.5MHz STEP-UP DC-DC CONVERTER AP3012
Ordering Information
AP3012 -
Circuit Type
Package
K: SOT-23-5
Package
SOT-23-5
BCD Semiconductor's Pb-free products, as designated with "E1" suffix in the part number, are RoHS compliant. Products with
"G1" suffix are available in green package.
Temperature
Range
-40 to 85
o
AP3012KTR-E1 AP3012KTR-G1 E6B G6B Tape & Reel
C
Part Number Marking ID
Lead Free Green Lead Free Green
E1: Lead Free
G1: Green
TR: Tape and Reel
Packing Type
May 2010 Rev. 1. 6 BCD Semiconductor Manufacturing Limited
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