AME5170

AME, Inc. AME5170 n General 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, www.DataSheet4U.com 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 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 20pF IN SW AME5170 FB GND 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 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 VOUT = 12V COUT 1µF R1 240K Ω IN SW AME5170 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 IN SW AME5170 FB GND R2 33KΩ Figure.3 Typical 20V Appl...