FAN2011 Datasheet | Fairchild Semiconductor

Features I I I I I I I I I 95% Efficiency, Synchronous Operation Adjustable Output Voltage from 0.8V to VIN 4.5V to 5.5V Input Voltage Range Up to 1.5A Output Current Fixed Frequency 1.3 MHz PWM Operation 100% Duty Cycle Low Dropout Operation Soft Start Excellent Load Transient Response 3x3mm 6-lead MLP Package Description The FAN2011/FAN2012 is a high-efficiency, low-noise synchronous PWM current mode DC-DC converter, designed for low voltage applications. It provides up to 1.5A continuous load current from the 4.5V to 5.5V input. The output voltage is adjustable over a wide range of 0.8V to VIN by means of an external voltage divider. The FAN2011 is always on, while the FAN2012 has an “Enable Input,” and the device can be put in the shutdown mode, in which the ground current falls below 1µA. A current mode control loop with a fast transient response ensures excellent line and load regulation. The fixed 1.3MHz switching frequency enables the user to choose a small, inexpensive external inductor and capacitor. Filtering is also easily acplished with very small ponents. Protection features include input under-voltage lockout, short circuit protection and thermal shutdown. Soft-start limits in-rush current during start-up conditions. The device is available in a 3x3mm 6-lead MLP package, making it possible to build a 1.5A plete DC/DC converter in a tiny space on the PCB. Applications I I I I I Hard Disk Drive Set Top Box Point of Load Power Notebook puters munications Equipment Typical Application R2 R1 VOUT 10K Ω FB 1 PGND 2 3 P1 (AGND) 6 5 4 NC VIN PVIN 10µF +5V R1 VOUT 4 x 10µF L1 R2 10K Ω FB 1 PGND SW 2 3 P1 (AGND) EN 6 5 4 VIN PVIN 10µF +5V L1 3.3µH 4 x 10µF 3.3µH FAN2011 Figure 1. Typical Application FAN2012 FAN2011/FAN2012 Rev. 1.0.2 .fairchildsemi. FAN2011/FAN2012 1.5A Low Voltage Current Mode Synchronous PWM Buck Regulator Pin Assignment Top View FB PGND SW 1 2 3 NC VIN PVIN FB PGND SW 1 2 3 EN VIN PVIN P1 (AGND) 5 4 P1...