IR3624MTRPBF

Data Sheet No.PD94714 revA IR3624MPBF HIGH FREQUENCY SYNCHRONOUS PWM BUCK CONTROLLER Features • • • • • • • • • Internal 600kHz Oscillator Operates with Single 5V or 12V Supply Programmable Over Current Protection Hiccup Current Limit Using MOSFET RDS(on) sensing Precision Reference Voltage (0.6V) Programmable Soft-Start Pre-Bias Start-up Thermal Protection 10-Lead MLPD Package Description The IR3624 is a PWM controller designed for high performance synchronous Buck DC/DC applications. The IR3624 drives a pair of external N-MOSFETs using a fixed 600kHz switching frequency allowing the use of small external components. The output voltage can be precisely regulated using the internal 0.6V reference voltage for low voltage applications. Protection such as Pre-Bias startup, hiccup current limit and thermal shutdown are provided to give required system level security in the event of fault conditions. Applications • • • • • Embedded Telecom Systems Distributed Point of Load Power Architectures Computing Peripheral Voltage Regulator Graphics Card General DC/DC Converters Vin Vc Vcc HDrv OCSet U1 Comp LDrv PGnd SS / SD Gnd Fb Vout Fig. 1: Typical application Circuit ORDERING INFORMATION PKG DESIG M M PACKAGE DESCRIPTION IR3624MPBF IR3624MTRPBF PIN PARTS PARTS COUNT PER TUBE PER REEL 10 121 ------10 -------3000 T&R ORIANTAION Figure A IR3624MPBF ABSOLUTE MAXIMUM RATINGS (Voltages referenced to GND) • • • • • • Vcc Supply Voltage ................................................… -0.5V to 16V Vc Supply Voltage …………………………………….. -0.5V to 30V Storage Temperature Range ..................................... -65°C To 150°C Operating Junction Temperature Range ................... -40°C To 150°C ESD Classification …………………………………..… JEDEC, JESD22-A114 Moisture Sensitivity Level ……………………………. JEDEC Level 1 @ 260oC 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 VCC LDrv PGnd HDrv VC 1 2 3 4 5 10 9 OCSet SS/SD Gnd Comp Fb Exposed Pad 8 7 6 10-Lead MLPD, 3x3mm ΘJA = 33o C/W * ΘJC = 2.1o C/W *Exposed pad on underside is connected to a copper pad through vias for 4-layer PCB board design 2 IR3624MPBF Block Diagram Vcc 3V 20uA 40uA 3V Bias Generator 3V 0.6V Vc Thermal Shutdown SS / SD 3uA OCP POR UVLO POR HDrv Vc 0.6V Error Amp PWM Comp Vcc R Q Fb S LDrv Comp 0.3V Oscillator Set R Q S SS POR PBias PGnd Ramp OCP Gnd 20uA OCSet Fig. 2: Simplified block diagram of the IR3624 3 IR3624MPBF Pin Description Pin Name 1 Vcc Description This pin provides power for the internal blocks of the IC as well as powers the low side driver. A minimum of 0.1uF, high frequency capacitor must be connected from this pin to power ground. Output driver for low side MOSFET Power Ground. This pin serves as a separate ground for the MOSFET drivers and should be connected to the system’s power ground plane. Output driver for high side MOSFET This pin powers the high side driver and must be connected to a voltage higher than bus voltage. A minimum of 0.1uF, high frequency capacitor must be connected from this pin to power ground. Inverting input to the error amplifier. This pin is connected directly to the output of the regulator via resistor divider to set the output voltage and provide feedback to the error amplifier. Output of error amplifier. An external resistor and capacitor network is typically connected from this pin to ground to provide loop compensation. Signal ground for internal reference and control circuitry. Soft start / shutdown. This pin provides user programmable soft-start function. Connect an external capacitor from this pin to ground to set the start up time of the output voltage. The converter can be shutdown by pulling this pin below 0.3V. Current limit set point. A resistor from this pin to drain of low side MOSFET will set the current limit threshold. 2 3 4 5 LDrv PGnd HDrv Vc 6 Fb 7 8 9 Comp Gnd SS/SD 10 OCSet 4 IR3624MPBF Recommended Operating Conditions Symbol Vcc Vc Fs Tj Definition Supply Voltage Supply Voltage Operating Frequency Junction Temperature Min 4.5 10 -40 Max 14 28 660 125 Units V V kHz o C Electrical Specifications Unless otherwise specified, these specification apply over Vcc=Vc=12V, 0oC