AME5170
AME5170 is Low Cost Micro Power Boost DC/DC Converter manufactured by AME.
Description
The AME5170 is a fixed off-time step-up DC/DC converter 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 ponents. AME5170 is designed to drive up to four white LEDs in series with a constant current from a single Li-lon battery. 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.
Low Cost Micro Power Boost DC/DC Converter n Typical Application
VIN 1.5V to 5V CIN 4.7µF L1 2.2µH VOUT = 5V COUT 4.7µF R1 100KΩ EN CF 20p F
R2 33KΩ
Figure.1 Typical 5V Application
VIN 1.5V to 5.5V CIN 4.7µF L1 10µH n Features l 0.7Ω Internal Switch l Use Small Surface Mount ponents 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 Ro HS Standards
VOUT = 12V COUT 1µF R1 240K Ω
EN GND FB
R2 27K Ω
Figure.2 Typical 12V Application n Applications l LCD Bias Supplies l White LED Back-Lighting l Handheld Devices l Digital Cameras l Portable Applications
EN VIN 1.5V to 5.5V CIN 4.7µF L1 10µH VOUT = 20V COUT 1µF R1 510KΩ
R2 33KΩ
Figure.3 Typical 20V Application
Rev.A.02 1
AME, Inc.
AME5170 n Typical Application
VIN 2.7V to 5.5V C IN .. 4.7µF L1 10µH VOUT COUT 1µF
Low Cost Micro Power Boost DC/DC Converter
FB R2 62Ω
Figure.4 White LED Application n Function Block Diagram
IN SW
+ FB
Enable p
1:8 VREF VIN
CL Adjust
Current Limit 400ns one Shot
Cs
+
Logic Control
Driver
Figure.5 Function Block Diagram
Rev.A.02
AME, Inc.
AME5170 n Pin Configuration
SOT-25/TSOT-25 Top...
