Using the ISL6402, ISL6402A Evaluation Board ® Application Note Using the Evaluation Board The ISL6402 and ISL6402A are high performance tripleoutput controllers offering control and protection features for 2 synchronous buck PWMs and 1 linear regulator. The ISL6402, ISL6402A evaluation boards highlight the operation of the IC in embedded DC-DC converter applications. Table 1 shows the available evaluation boards. TABLE 1. EVALUATION BOARDS BOARD NAME IC PACKAGE ISL6402EVAL4 ISL6402IR 28 Ld QFN ISL6402AEVAL4 ISL6402AIR 28 Ld QFN Recommended Test Equipment • • • • A 4.5V-24V, 5A capable power supply An electronic load Four channel oscilloscope with probes Precision digital multimeters AN1130 To independently shutdown the PWMs, the SD1 or SD2 pin can be pulled to GND using the on board jumpers, JP2 and JP3 respectively. SYNC Function The ISL6402, ISL6402A can synchronize to another ISL6402, ISL6402A. The SYNC pin sends out pulses at 4 times the switching frequency for the ISL6402A and 16 times the switching frequency of the ISL6402. The SYNC function is bidirectional so if two or more ICs are SYNC, only 1 will be the master. All other ICs will SYNC to the master. The SYNC feature can be evaluated on the eval board. The SYNC pin us pulled to VCC_5V through R17. This resistor should be removed an a 1K resistor should be placed at R19. With the 1K resistor from SYNC to ground, the SYNC pulses can be observed on a scope. Power Good Power and Load Connections Input Voltage - The input power supply can be connected in two different ways depending on the input voltage supplied to the PWM power stage. When connecting to a 5.6V-20V power supply, connect the positive lead of the power supply to VIN (P1) post and the ground lead of the supply to the GND (P2) post. When connecting to a 4.5V-5.5V input, the Vin (P1) and VCC_5V (P10) posts must be shorted using the jumper (JP1) before connecting the positive lead of the supply to the Vin (P1) post and the ground lead to the GND (P2) post. The input voltage to the linear regulator can be supplied from a 3.3V/5V power supply by connecting the positive lead of the power supply to the VIN3 (P13) post and the ground terminal to the GND (P14) post. Output Adjustment Change the respective output voltage feedback resistors to modify the output voltage: R V OUT1 = 0.8 ⋅ 1 + ------7- R 8 May 2004 When both PWMs are within ±10% of their set value and the linear regulator output is within 75% of its set value, the PGOOD signal will go high. The open drain PGOOD pin is pulled HIGH to VCC_5V on the board. The PGOOD circuitry monitors the FBx pin of each regulated output to determine if the outputs are in regulation. If the linear controller is not used, the VOUT3 post P15 can be tied to VCC_5V so that the PGOOD function can be evaluated without the linear output. PGOOD can be monitored at post P8. Overcurrent Protection The overcurrent thresholds can be adjusted on the ISL6402, ISL6402A evaluation board. The current sense resistors, ISENSE, are set at 1.4K. The overcurrent set resistor is 120K. The overcurrent trip point can be adjusted by modifying ROCSET, R11 and R12: 7 ⋅ R CS R OCSET = ------------------------------------I OC ⋅ R DS ( on ) R9 V OUT2 = 0.8 ⋅ 1 + --------- R 10 R 15 - V OUT3 = 0.8 ⋅ 1 + --------R 16 Soft Start and Shutdown The soft start capacitors can be adjusted for sequencing of the output voltages, PWM startup tracking, and/or to adjust the startup current required to charge the output capacitors. 0.8V t SS ( PWM1 ) = C 6 ⋅ -----------5µA ROCSET is the overcurrent set resistor, RCS is the current sense resistor, IOC is the desired overcurrent trip point, and rDS(ON) is the on resistance of the respective PWM’s lower MOSFET. Refer to the ISL6402, ISL6402A datasheets for more information on how to select the current sense and overcurrent select resistors. 0.8V t SS ( PWM2 ) = C 5 ⋅ -----------5µA 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 321-724-7143 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2004. All Rights Reserved All other trademarks mentioned are the property of their respective owners. ISL6402AEVAL4 Schematic 2 Application Note 1130 Application Note 1130 ISL6402AEVAL4 Bill of Materials ITEM REFERENCE QTY PART NUMBER PART TYPE 1 U1 1 ISL6402AIR IC, Linear Dual PWM Controller, 1.4MHz 28 QFN Intersil 2 D1, D2 2 BAT54WT1 Diode, Schottky 30V, 200mA SOT-323 On Semi 3 Q1, Q2 2 FDS6990S MOSFET, Dual N-Chan, 30V, 7.5A, 0.022Ω SOIC-8 Fairchild 4 Q3 1 IRF7404 MOSFET, Power, HEXFET P-Chan, 20V, 6.7A, 0.04Ω SOIC-8 IR 5 L1, L2 2 ETQP6F3R2HFA Power Choke Coil 3.2µH, 25%, 8.6A PCC-N6 PANASONIC 6 L3 1 BLM21PG300SN1 Ferrite Bead SM_0805 Murata 7 C1, C3 2 TMK325BJ106KM Capacitor, Ceramic, X5R 10µF, 10%, 25V SM_1210 Taiyo Yuden/Generic 8 C2 1 12103D475KAT2A Capacitor, Ceramic, XR5 4.7µF, 10%, 25V SM_1210 AVX/Generic 9 C4, C24, C28 3 12063C105KAT2A Capacitor, Ceramic, X7R 1.0µF, 10%, 25V SM_1206 AVX/Generic 10 C9, C10, C13, C14 4 0805ZC105KAT2A Capacitor, Ceramic, X7R 1.0µF, 10%, 10V SM_0805 AVX/Generic 11 C11A, C12A 2 10TPB150ML CASE-D3L SANYO 12 C11B, C11C, C12B, C12C (DNP) 4 Capacitor, Tantalum DESCRIPTION 150µF, 20%, 10V Capacitor, Tantalum PKG. VENDOR CASE-D3L SANYO 13 C15, C16 (DNP) 2 SM_0805 AVX/Generic 14 C5, C6, C7, C8, C17, C18, C20 7 08053C104KAT2A Capacitor, Ceramic, X7R 0.1µF, 10%, 25V Capacitor, Ceramic SM_0805 AVX/Generic 15 C19 1 16TPB47M Capacitor, Tantalum 47µF, 20%, 16V CASE-D3 SANYO 16 C21 1 25SP56M Capacitor, Aluminum 56µF, 20%, 25V Radial SANYO 17 C22 1 0603YC104KAT2A Capacitor, Ceramic, X7R 0.1µF, 10%, 16V SM_0603 AVX/Generic 18 C23 1 1210ZC106MAT2A Capacitor, Ceramic, X7R 10µF, 20%, 10V SM_1210 AVX/Generic 19 R1, R2, R17, R18 4 Resistor, Film 100kΩ, 1%, .1W SM_0603 Panasonic 20 R3, R4 2 Resistor, Film 1.4kΩ, 1%, .1W SM_0603 Panasonic 21 R5, R6 (DNP) 0 Resistor, Film TBD SM_0805 Panasonic 22 R7 1 Resistor, Film 23.7kΩ, 1%, 1/16W SM_0603 Panasonic 23 R8 1 Resistor, Film 7.50kΩ, 1%, 1/16W SM_0603 Panasonic 24 R9 1 Resistor, Film 4.02kΩ, 1%, 1/16W SM_0603 Panasonic 25 R10 1 Resistor, Film 8.06kΩ, 1%, 1/16W SM_0603 Panasonic 26 R11, R12 2 Resistor, Film 120kΩ, 1%, 1/16W SM_0603 Panasonic 27 R13 1 Resistor, Film 100Ω, 1%, .1W SM_0805 Panasonic 28 R14 1 Resistor, Film 2.7Ω, 5%, 1/16W SM_0603 Panasonic 29 R15 1 Resistor, Film 17.4kΩ, 1%, 1/16W SM_0603 Panasonic 30 R16 1 Resistor, Film 8.25kΩ, 1%, 1/16W SM_0603 Panasonic 31 R19 (DNP) 1 Resistor, Film SM_0603 Panasonic Misc. 32 P1 - P16 16 1514-2 Turrett Post Terminal post, through hole, 1/4 inch tall PTH 33 JP1, JP2, JP3 3 68000-236-1X2 Header 1X2 Break Strip GOLD [email protected]" 34 JP1 (DNP) 0 S9001-ND Jumper 2 pin jumper Digikey 35 JP2 - JP3 2 S9001-ND Jumper 2 pin jumper Digikey 36 SP1, SP2 2 129-0701-202 Terminal, Scope Probe Terminal, Scope Probe Johnson 3 Application Note 1130 ISL6402AEVAL4 Layout TOP SILK LAYER 1 LAYER 2 LAYER 3 LAYER 4 BOTTOM SILK 4 ISL6402EVAL4 Schematic 5 Application Note 1130 Application Note 1130 ISL6402EVAL4 Bill of Materials ITEM REFERENCE QTY PART NUMBER PART TYPE 1 U1 1 ISL6402IR IC, Linear Dual PWM Controller, 300kHz 28 QFN 2 D1, D2 2 BAT54WT1 Diode, Schottky 30V, 200mA SOT-323 On Semi 3 Q1, Q2 2 FDS6990S MOSFET, Dual N-Chan, 30V, 7.5A, 0.022Ω SOIC-8 Fairchild 4 Q3 1 IRF7404 MOSFET, Power, HEXFET P-Chan, 20V, 6.7A, 0.04Ω SOIC-8 IR 5 L1, L2 2 ETQP6F6R4HFA Power Choke Coil PCC-N6 PANASONIC 6 L3 1 BLM21PG300SN1 Ferrite Bead 7 C1, C3 2 TMK325BJ106KM Capacitor, Ceramic, X5R 10µF, 10%, 25V SM_1210 Taiyo Yuden/Generic 8 C2 1 12103D475KAT2A Capacitor, Ceramic, XR5 4.7µF, 10%, 25V SM_1210 AVX/Generic 9 C4, C24, C28 3 12063C105KAT2A Capacitor, Ceramic, X7R 1.0µF, 10%, 25V SM_1206 AVX/Generic 10 C9, C10, C13, C14 4 0805ZC105KAT2A Capacitor, Ceramic, X7R 1.0µF, 10%, 10V SM_0805 AVX/Generic 11 C11A, C11B, C12A, C12B 4 10TPB220M 220µF, 20%, 10V CASE-D4 SANYO 12 C11C, C12C (DNP) 2 Capacitor, Tantalum CASE-D4 SANYO 13 C15, C16 (DNP) 2 Capacitor, Ceramic SM_0805 AVX/Generic 14 C5, C6, C7, C8, C17, C18, C20 7 08053C104KAT2A Capacitor, Ceramic, X7R 0.1µF, 10%, 25V SM_0805 AVX/Generic 15 C19 1 16TPB47M Capacitor, Tantalum 47µF, 20%, 16V CASE-D3 SANYO 16 C21 1 25SP56M Capacitor, Aluminum 56µF, 20%, 25V Radial 17 C22 1 0603YC104KAT2A Capacitor, Ceramic, X7R 0.1µF, 10%, 16V SM_0603 AVX/Generic 18 C23 1 1210ZC106MAT2A Capacitor, Ceramic, X7R 10µF, 20%, 10V SM_1210 AVX/Generic 19 R1, R2, R17, R18 4 Resistor, Film 100kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 20 R3, R4 2 Resistor, Film 1.4kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 21 R5, R6 (DNP) 0 Resistor, Film TBD SM_0805 Panasonic/Generic 22 R7 1 Resistor, Film 23.7kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 23 R8 1 Resistor, Film 7.50kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 24 R9 1 Resistor, Film 4.02kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 25 R10 1 Resistor, Film 8.06kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 26 R11, R12 2 Resistor, Film 120kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 27 R13 1 Resistor, Film 100Ω, 1%, 0.1W SM_0805 Panasonic/Generic 28 R14 1 Resistor, Film 2.7Ω, 5%, 1/16W SM_0603 Panasonic/Generic 29 R15 1 Resistor, Film 17.4kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 30 R16 1 Resistor, Film 8.25kΩ, 1%, 1/16W SM_0603 Panasonic/Generic 31 R19 (DNP) 1 Resistor, Film Capacitor, Tantalum DESCRIPTION 6.4µH, 30%, 6.2A PKG. VENDOR Intersil SM_0805 Murata SANYO SM_0603 Panasonic/Generic Misc. 32 P1 - P16 16 1514-2 Turrett Post Terminal post,through hole, 1/4 inch tall PTH 33 JP1, JP2, JP3 3 68000-236-1X2 Header 1X2 Break Strip GOLD [email protected]" 34 JP1 (DNP) 0 S9001-ND Jumper 2 pin jumper Digikey 35 JP2 - JP3 2 S9001-ND Jumper 2 pin jumper Digikey Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that the Application Note or Technical Brief is current before proceeding. For information regarding Intersil Corporation and its products, see www.intersil.com 6 Application Note 1130 ISL6402EVAL4 Layout TOP SILK LAYER 1 LAYER 2 LAYER 3 LAYER 4 BOTTOM SILK 7