IRU3137

Data Sheet No. PD94700 IRU3137 8-PIN SYNCHRONOUS PWM CONTROLLER FEATURES 1A Peak Output Drive Capability 0.8V Reference Voltage Shuts off both drivers at shorted output and shutdown Operating with single 5V or 12V supply voltage Stable with ceramic capacitors Internal 200KHz Oscillator Soft-Start Function Protects the output when control FET is shorted Synchronous Controller in 8-Pin Package DESCRIPTION The IRU3137 controller IC is designed to provide a low cost and high performance synchronous Buck regulator for on-board DC to DC converter applications. The output voltage can be set as low as 0.8V and higher voltage can be obtained with an external voltage divider. High peak current gate drivers provide fast switching transition for applications requiring high output current in the range of 15A to 20A. This device features an internal 200KHz oscillator, under-voltage lockout for both Vcc and Vc 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 DDR Memory Application Low voltage distributed DC-DC Graphic Cards Low cost on-board DC to DC such as 5V to 2.5V, 1.8V or 0.8V TYPICAL APPLICATION 12V C3 1uF C4 1uF C2 4x 150uF Optional L1 1uH C1 47uF 5V Vcc Vc HDrv D1 Q1 IRF7832 L2 2.2uH Q2 IRF7832 SS/SD C8 0.1uF 2.5V @ 15A C7 3x 330uF 40mΩ , Poscap U1 LDrv IRU3137 Comp Fb R4 30K R3 2.15K R5 1K, 1% C9 3300pF Optional Gnd Figure 1 - Typical application of IRU3137. PACKAGE ORDER INFORMATION TA (°C) 0 To 70 Rev. 1.0 06/22/04 DEVICE IRU3137CS PACKAGE 8-Pin Plastic SOIC NB (S) www.irf.com FREQUENCY 200KHz 1 IRU3137 ABSOLUTE MAXIMUM RATINGS Vcc Supply Voltage .................................................. Vc Supply Voltage .................................................... Storage Temperature Range ...................................... Operating Junction Temperature Range ..................... -0.5V - 25V -0.5V - 25V -65°C To 150°C 0°C To 125°C CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. PACKAGE INFORMATION 8-PIN PLASTIC SOIC NB (S) Fb 1 Vcc 2 LDrv 3 Gnd 4 θJA=160°C/W 8 SS 7 Comp 6 Vc 5 HDrv ELECTRICAL SPECIFICATIONS Unless otherwise specified, these specifications apply over Vcc=5V, Vc=12V and TA=0 to 70°C. Typical values refer to TA=25 C. PARAMETER Reference Voltage Fb Voltage Fb Voltage Line Regulation UVLO UVLO Threshold - Vcc UVLO Hysteresis - Vcc UVLO Threshold - Vc UVLO Hysteresis - Vc UVLO Threshold - Fb UVLO Hysteresis - Fb Supply Current Vcc Dynamic Supply Current Vc Dynamic Supply Current Vcc Static Supply Current Vc Static Supply Current Soft-Start Section Charge Current SYM V FB LREG UVLO Vcc UVLO Vc UVLO Fb TEST CONDITION MIN 0.784 TYP 0.800 MAX 0.816 1.6 4.5 3.65 0.5 UNITS V mV V V V V V V mA mA mA mA µA 5