IR3637SPBF

Data Sheet No. PD94713 IR3637SPBF 1% ACCURATE SYNCHRONOUS PWM CONTROLLER FEATURES 0.8V Reference Voltage Operates with a single 5V Supply Voltage Internal 400kHz Oscillator Soft-Start Function Fixed Frequency Voltage Mode Short Circuit Protection DESCRIPTION The IR3637 controller IC is designed to provide a simple synchronous Buck regulator for on-board DC to DC applications in a small 8-pin SOIC. The output voltage can be precisely regulated using the internal 0.8V reference voltage for low voltage applications. The IR3637 operates at a fixed internal 400kHz switching frequency to reduce the component size. The device features under-voltage lockout for both input supplies, an external programmable soft-start function as well as output under-voltage detection that latches off the device when an output short is detected. APPLICATIONS Computer Peripheral Voltage Regulator Memory Power supplies Graphics Card Low cost on-board DC to DC TYPICAL APPLICATION 12V C3 5V C2 C1 Vc Vcc HDrv Q1 D1 L1 Vout Q2 C6 SS/SD C4 IR3637 LDrv Comp Fb Gnd R1 C5 R3 R2 Figure 1 - Typical application of IR3637. ORDERING INFORMATION PKG DESIG S S PACKAGE PIN PARTS PARTS T&R DESCRIPTION COUNT PER TUBE PER REEL Oriantation IR3637SPBF 8 95 -----Fig A IR3637STRPBF 8 ------2500 Rev. 1.1 06/16/05 www.irf.com 1 IR3637SPBF ABSOLUTE MAXIMUM RATINGS Vcc Supply Voltage ................................................ Vc Supply Voltage .................................................. Storage Temperature Range ..................................... Operating Junction Temperature Range ..................... ESD Classification ................................................. Moisture Sensitivity Level ........................................ 16V 25V -65°C To 150°C 0°C To 125°C HMB Class 2 (2KV) JEDEC Standard JEDEC Level 1 @ 260°C Caution: Stresses above those listed in “Absolute Maximum Rating” may cause permanent damage to the device. These are stress ratings only and function of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to “Absolute Maximum Rating” conditions for extended periods may affect device reliability PACKAGE INFORMATION Fb 1 Vcc 2 LDrv 3 Gnd 4 8 SS/SD 7 Comp 6 Vc 5 HDrv Recommended Operating Conditions Parameter Vcc Vc Min 4.5 8 Max 5.5 14 Units V V θJA=154°C/W θJC=41.2°C/W ELECTRICAL SPECIFICATIONS Unless otherwise specified, these specifications apply over Vcc=5V, Vc=12V and 0°C