IRDC3039EVAL IRU3039 EVALUATION BOARD USER GUIDE INTRODUCTION SPECIFICATION DATA The IRU3039 controller IC is designed to provide a synchronous Buck regulator and is targeted for applications where the cost and size is critical. The IRU3039 operates with a single input supply up to 20V. The output voltage can be programmed as low as 0.8V for low voltage applications. Selectable current limit is provided to tailor to external MOSFET's on-resistance for optimum cost and performance. The IRU3039 features an uncommitted error amplifier for tracking output voltage and is capable of sourcing or sinking current for applications such as DDR bus termination. Switcher: VIN = 18V VOUT = 3.3V IOUT = 8A DVOUT = 100mV FS = 200KHz This device features a programmable switching frequency set from 200KHz to 400KHz, 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. INPUT/OUTPUT CONNECTIONS The following is the input/output connections: Inputs: JP1: Input (+18V), Gnd The connection points is shown in Figure 1. Connect the power supply cables according to this figure, minimize wire lengths to reduce losses in the wire. Test point J1 provides easy connections for the oscilloscope voltage probe to monitor the output voltage. Outputs: JP2: VOUT (+3.3V), Gnd Rev. 1.0 05/30/03 www.irf.com 1 IRDC3039EVAL CONNECTION DIAGRAM Load 0 - 8A +20V Gnd Power Supply 6A Supply Figure 1 - Connection diagram of evaluation-board for IRU3039. 2 www.irf.com Rev. 1.0 05/30/03 IRDC3039EVAL LAYOUT The four layers for IRU3039 evaluation board are shown in Figures 2.1-2.4. The input capacitors are all located close to the MOSFETs. All the decoupling capacitors, charge pump capacitor and feedback components are located close to IC. The feedback resistors are tied to the output voltage at the point of regulation. The middle layers are dedicated to Power Ground and Analog Ground. Analog Ground is kept separated from the Power Ground and it is connected at a single point as shown in figure 2.1. Figure 2.1 - Top layer of evaluation-board for IRU3039. Rev. 1.0 05/30/03 www.irf.com 3 IRDC3039EVAL PGnd AnGnd Figure 2.2 - Middle layer 1. PGnd Figure 2.3 - Middle layer 2. Figure 2.4 - Bottom layer. 4 www.irf.com Rev. 1.0 05/30/03 Rev. 1.0 05/30/03 GND VIN www.irf.com Open R13 Open 0.1uF R7 14K VDDQ C2 R12 Open 5600pF C7 C1 15uF 15 VO2 C3 1uF C10 0.1uF R11 0V 20 19 18 17 VP FB VREF 1 COMP SS / SD 16 OCSET 1uH L1 NC 2 13 NC 12 RT VCC 4 LDRV PGND GND NC 5 C11 1uF VC HDRV 11 NC 6 7 8 9 10 C13A 1uF 0V 5.76K R5 R4 0V R3 15uF 25V C2C D2 BAT54 15uF 25V C2B Q2 IRF7458 Q1 IRF7466 R14 Open Figure 3 - Schematic of evaluation-board for IRU3039. NC 3 U1 IRU3039 14 NC Open R6 15uF 25V C2A L2 C5 4.7uH R8 4.7V C8 470pF Open R2 C9B C9C R10 1K R9 3.16K 330uF 330uF Open 40mV 40mV C9A D1 BAT54S 1uF C12 J1 GND VOUT C13 1uF JP2 SCHEMATIC C6 JP1 R1 0V IRDC3039EVAL 5 IRDC3039EVAL BILL OF MATERIAL Ref Desig Description Q1 MOSFET Q2 MOSFET U1 Controller D1 Schottky Diode D2 Schottky Diode L1 Inductor L2 Inductor C1,C2A,B,C Cap, Poscap C5,6,10 Capacitor C7 Capacitor C8 Capacitor C9A,B Cap, Poscap C3,11,12,13 Capacitor C13A Capacitor R4 Resistor R7 Resistor R8 Resistor R9 Resistor R10 Resistor R1,3,5,11 Resistor R2,6,12,13,14 Resistor C2,C9C Capacitor JP1,JP2 Connector J1 Scope Probe 6 Value Qty Part# 30V, 12.5mV, 11A 1 IRF7466 30V, 8mV, 14A 1 IRF7458 Synchronous PWM 1 IRU3039 Fast Switching 1 BAT54S Fast Switching 1 BAT54 1mH, 3A 1 DS1608C-102 4.7mH, 13A 1 DO5022P-472HC 15mF, 25V 4 25TQC15M 0.1mF, Y5V, 25V 3 ECJ-2VF1E104Z 5600pF, X7R, 50V 1 ECU-V1H562KBG 470pF, X7R, 50V 1 ECJ-2VC1H471J 330uF, 40mV 2 6TPB-330M 1mF, Y5V, 16V 4 ECJ-2VF1C105Z 1mF, X7R, 25V 1 ECJ-3YB1E105K 5.76K, 1% 1 14K, 1% 1 4.7V, 1% 1 3.16K, 1% 1 1K, 1% 1 0V 4 Open(NA) 5 Open 2 2 Positive Terminal 2 ED1973-ND 1 131-50310-00 www.irf.com Manuf IR IR IR IR IR Coilcraft Coilcraft Sanyo Panasonic Panasonic Panasonic Sanyo Panasonic Panasonic Web site (www.) irf.com coilcraft.com sanyo.com maco.panasonic.co.jp sanyo.com maco.panasonic.co.jp Digikey Textronix Rev. 1.0 05/30/03 IRDC3039EVAL TYPICAL OPERATING CHARACTERISTICS Test Conditions: VIN=20V, VOUT=3.3V, IOUT=0-8A, Fs=200KHz Figure 4 - Normal condition at No Load. Ch1: HDrv, Ch2: LDrv, Ch4: Inductor Current Figure 5 - Soft-Start. Ch1: VIN, Ch2: VOUT, Ch3: VOUT2, Ch4: Vss Figure 6 - Soft-Start pin grounded. Ch1: HDrv, Ch2: LDrv Figure 7 - Output Ripple. Ch1: Output Ripple, Ch2: HDrv, Ch3: LDrv, Ch4: Inductor Current Rev. 1.0 05/30/03 www.irf.com 7 IRDC3039EVAL TYPICAL OPERATING CHARACTERISTICS Test Conditions: VIN=20V, VOUT=3.3V, IOUT=0-8A, Fs=200KHz 8A 0A Efficiency (%) Figure 8 - Output shorted at start up. Ch1: VOUT, Ch3: Vss, Ch4: Inductor Current Figure 9 - Load Transient Response Ch1: VOUT, Ch3: Output Current 90 88 86 84 82 80 78 76 74 72 70 0 1 2 3 4 5 6 7 8 9 10 11 Output Current (A) Figure 10 - Efficiency Measurement. VIN=20V, VOUT=3.3V IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 TAC Fax: (310) 252-7903 Visit us at www.irf.com for sales contact information Data and specifications subject to change without notice. 02/01 8 www.irf.com Rev. 1.0 05/30/03