AME5170 Datasheet, PDF (1/13 Pages) Analog Microelectronics – Low Cost Micro Power Boost DC/DC Converter

AME, Inc.
AME5170
Low Cost Micro Power
Boost DC/DC Converter
n General Description
The AME5170 is a fixed off-time step-up DC/DC con-
verter in a small SOT-25 package. The AME5170 is ideal
for LCD panels requiring low current and high efficiency
as well as LED application for cellular phone backlighting,
PDAs, and other hand-held devices. The low 400ns off
time allows the use of tiny external components.
AME5170 is designed to drive up to four white LEDs in
series with a constant current from a single Li-lon bat-
tery. To control LED brightness, the LED current can be
adjusted by applying a PWM (pulse width modulated)
signal with a frequency range of 100Hz to 50KHz to the
EN pin.
n Typical Application
V_IN
1.5V to 5V
C_IN
4.7µF
L1
2.2µH
IN
SW
AME5170
EN
R1
100KΩ
V_OUT = 5V
CF
20pF
C_OUT
4.7µF
GND
FB
R2
33KΩ
n Features
l 0.7Ω Internal Switch
l Use Small Surface Mount Components
l Adjust Output Voltage up to 28V
l Input under Voltage Lockout
l 0.1µA Shutdown Current Typical
l Small SOT-25 Package
l All AME's Lead Free Products Meet RoHS
Standards
n Applications
l LCD Bias Supplies
l White LED Back-Lighting
l Handheld Devices
l Digital Cameras
l Portable Applications
Figure.1 Typical 5V Application
V_IN
1.5V to 5.5V
C_IN
4.7µF
L1
10µH
IN
SW
AME5170
EN
GND
FB
V_OUT = 12V
R1
240KΩ
C_OUT
1µF
R2
27KΩ
Figure.2 Typical 12V Application
V_IN
1.5V to 5.5V
C_IN
4.7µF
L1
10µH
IN
SW
AME5170
EN
GND
FB
V_OUT = 20V
R1
510KΩ
C_OUT
1µF
R2
33KΩ
Rev.A.02
Figure.3 Typical 20V Application
1