ISL85001EVAL1Z: 1A Regulator Standard Buck PWM ® Application Note December 1, 2008 AN1443.0 Description Recommended Equipment The ISL85001EVAL1Z REV A kit is intended for use by individuals with requirements for Point-of-Load applications sourcing from 4.5V to 25V. The ISL85001EVAL1Z evaluation board is used to demonstrate the performance of the ISL85001 standard buck regulator. The Following Materials are Recommended to Perform Testing: The ISL85001 is offered in a 4mmx3mm 12 Ld DFN package with 1mm maximum height. The complete converter occupies less than 0.425in2 area. • 0V to 25V Power Supply with at Least 5A Source Current Capability, Battery, Notebook AC Adapter • One Electronic Load Capable of Sinking Current up to 5A • Digital Multimeters (DMMs) • 100MHz Quad-Trace Oscilloscope Features • Signal Generator • Standard Buck Controller with Integrated Switching Power MOSFET Quick Setup Guide • Integrated Boot Diode 1. Ensure that the circuit is correctly connected to the supply and loads prior to applying any power. • Input Voltage Range - Fixed 5V ±10% - Variable 5.5V to 25V 2. Connect the bias supply to VIN, the plus terminal to TP1 (VIN) and the negative return to TP2 (GND). • PWM Output Voltage Adjustable from 0.6V to 19V with Continuous Output Current up to 1A 4. Turn on the power supply. 3. Verify that SW1 is on ENABLE. • Voltage Mode Control with Voltage Feed-Forward 5. Verify the PG is on and the output voltage is 2.5V for VOUT(TP3). • Fixed 500kHz Switching Frequency Evaluating the Other Output Voltage • Externally Adjustable Soft-Start Time The ISL85001EVAL kit outputs are preset to 2.5V; however, it can be programmed using resistor dividers using Equation 1: • Output Undervoltage Protection • Enable Inputs R 1 ⋅ 0.6V R 2 = ---------------------------------V OUT – 0.6V • PGOOD Output • Overcurrent Protection (EQ. 1) The output voltage programming resistor R2 will depend on on the feedback resistor R1, as referred to in Figure 1. The value of R1 is typically between 1kΩ and 10kΩ. If the output voltage desired is 0.6V, then R2 is left opened. • Thermal Overload Protection • Internal 5V LDO regulator Applications VOUT • General Purpose R1 • WLAN Cards-PCMCIA, Cardbus32, MiniPCI Cards-Compact Flash Cards + EA R2 • Hand-Held Instruments • LCD Panel 0.6V REFERENCE • Set-top Box FIGURE 1. EXTERNAL RESISTOR DIVIDER What’s Inside The Evaluation Board Kit contains the following materials: • The ISL85001 EVAL REV A board • The ISL85001 datasheet TABLE 1. SWITCH 1 SETTINGS SW1 1 ENABLE SW1 OPERATING MODE Enable or disable the buck controller • This EVAL KIT document 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2008. All Rights Reserved All other trademarks mentioned are the property of their respective owners. Application Note 1443 ISL85001EVAL1Z Schematic C1 2 30K 1 R2 2200PF C2 10K VIN 1 1 1 C20 2 TP3 C8 EP 1 4 SP1 2 3 0.1UF VDD 4 SP2 1 1 2 1 1 C9 BOOT 2 8 C21 GND VOUT 1 OPEN BOOT PG L1 PHASE 2 67 13 PHASE EN 10 9 C12 5 11 47UF C13 4 VIN PHASE SS 2 EN PG COMP 3 0.1UF VIN FB 1 3 1 TP2 12 D1 C4 1 2 2 2 2 TP1 GND 1 1 2 COMP 3 1 U1 OPEN 1 C10 3.16K TP16 FB 1 PG 10UF C11 D3 1 C3 470PF R4 2N7002 Q4 2 301 220UF R3 47PF 1UF 10K R21 R1 2 R20 2.43K VDD 1 TP4 2 ISL8500IRZ TP13 R30 VIN OPEN POPULATE R30 IF VIN <6V ONLY 1 R12 100K VDD ON EN 3 SW1 1 2 OFF 2 AN1443.0 December 1, 2008 Application Note 1443 ISL85001EVAL1Z Bill of Materials PART NUMBER REFERENCE DESIGNATOR QTY UNITS DESCRIPTION MFR MANUFACTURER PART ISL85001EVAL1ZREVAPCB 1 ea See Label-Rename Board PWB-PCB, ISL85001EVAL1Z, REVA, ROHS TITAN ISL85001EVAL1ZREVAPCB C1608X7R1H104K-T 1 ea C9 CAPACITOR, SMD, 0603, 0.10µF, 50V, 10%, X7R TDK C1608X7R1H104K H1044-00104-16V10-T 1 ea C4 CAP, SMD, 0402, 0.1µF, 16V, 10%, X7R, ROHS MURATA GRM36X7R104K016AD H1044-00222-50V10-T 1 ea C1 CAP, SMD, 0402, 2200pF, 50V, 10%, X7R, ROHS PANASONIC ECJ-0EB1H222K H1044-00470-50V5-T 1 ea C2 CAP, SMD, 0402, 47pF, 50V, 5%, NPO, ROHS MURATA GRM36COG470J050AQ H1044-00471-50V10-T 1 ea C3 CAP, SMD, 0402, 470pF, 50V, PANASONIC 10%, X7R, ROHS ECJ-0EB1H471K H1045-00105-6R3V10-T 1 ea C8 CAP, SMD, 0603, 1µF, 6.3V, 10%, X5R, ROHS PANASONIC ECJ1VB0J105K H1065-00106-25V10-T 1 ea C10 CAP, SMD,1206,10µF, 25V, 10%, X5R, ROHS VENKEL C1206X5R250-106KNE H1082-00476-16V20-T 1 ea C12 CAP, SMD, 1210, 47µF, 16V, 20%, x5R, ROHS TDK C3225X5R1C476M IHLP2525CZER220M11 1 ea L1 COIL-PWR INDUCTOR, SMD, 6.9x6.5, 22µH, 20%, 7A, ROHS VISHAY IHLP2525CZER220M11 131-4353-00 2 ea SP1, SP2 CONN-SCOPE PROBE TEST TEKTRONIX PT, COMPACT, PCB MNT, ROHS 131-4353-00 1514-2 4 ea TP1 to TP4 CONN-TURRET, TERMINAL POST, TH, ROHS KEYSTONE 1514-2 5002 2 ea TP13, TP16 CONN-MINI TEST POINT, VERTICAL, WHITE, ROHS KEYSTONE 5002 B340LB-13-F-T 1 ea D1 DIODE-SCHOTTKY, SMD, SMB, 2P, 40V, 3A LOW VF, ROHS DIODES INC. B340LB-13-F LTST-C170CKT 1 ea D3 LED-GaAs RED, SMD, 2x1.25mm,100mW, 40mA, 10mcd, ROHS LITEON/VISHA Y LTST-C170CKT ISL85001IRZ 1 ea U1 IC-2A BUCK REGULATOR, 12P, DFN, 4x3, ROHS INTERSIL ISL85001IRZ 2N7002-7-F-T 1 ea Q4 TRANSISTOR, N-CHANNEL, 3LD, SOT-23, 60V, 115mA, ROHS DIODES,INC. 2N7002-7-F H2510-01002-1/16W1-T 1 ea R2 RES, SMD, 0402, 10k, 1/16W, PANASONIC 1%, TF, ROHS ERJ-2RKF1002 H2510-01003-1/16W1-T 1 ea R12 RES, SMD, 0402, 100k, 1/16W, 1%, TF, ROHS ERJ2RKF1003 H2510-03002-1/16W1-T 1 ea R1 RES, SMD, 0402, 30k, 1/16W, YAGEO 1%, TF, ROHS RC0402FR-0730KL H2510-03010-1/16W1-T 1 ea R3 RES, SMD, 0402, 301Ω, 1/16W, 1%, TF, ROHS ERJ-2RKF3010X 3 PANASONIC PANASONIC AN1443.0 December 1, 2008 Application Note 1443 ISL85001EVAL1Z Bill of Materials (Continued) PART NUMBER QTY UNITS REFERENCE DESIGNATOR DESCRIPTION MFR H2510-03161-1/16W1-T 1 ea R4 RES, SMD, 0402, 3.16k, 1/16W, 1%, TF, ROHS H2511-01002-1/10W1-T 1 ea R21 RES, SMD, 0603, 10k, 1/10W, KOA 1%, TF, ROHS RK73H1JT1002F H2511-02431-1/10W1-T 1 ea R20 RES, SMD, 0603, 2.43k, 1/10W, 1%, TF, ROHS VENKEL CR0603-10W-2431FT H2511-DNP 0 ea R30 RES, SMD, 0603, DNPPLACE HOLDER, ROHS GT11MSCBE-T 1 ea SW1 SWITCH-TOGGLE, SMD, ULTRAMINI, 1P, SPST MINI C&K COMPONENTS GT11MSCKE 4-40x1/2-SCREW 4 ea Four corners SCREW, 4-40x1/2in, PAN, NYLON, PHILLIPS, ROHS 4-40x3/4-STANDOFF 4 ea Four corners STANDOFF, 4-40x3/4in, F/F, HEX, NYLON KEYSTONE 1902D 5x8-STATIC-BAG 1 ea Place assy in bag. BAG, STATIC, 5x8, ZIP LOC INTERSIL 212403-013 DNP 0 ea C11, C13, C20, C21 DO NOT POPULATE OR PURCHASE LABEL-RENAME BOARD 1 ea RENAME PCB TO: ISL85001EVAL1Z LABEL-SERIAL NUMBER 1 ea 4 VENKEL MANUFACTURER PART CR0402-16W-3161FT LABEL, TO RENAME BRD LABEL, FOR SERIAL NUMBER AND BOM REV # AN1443.0 December 1, 2008 Application Note 1443 ISL85001EVAL1Z Board Layout ISL85001EVAL1Z FIGURE 2. TOP COMPONENTS FIGURE 3. TOP LAYER ETCH 5 AN1443.0 December 1, 2008 Application Note 1443 ISL85001EVAL1Z Board Layout (Continued) FIGURE 4. BOTTOM LAYER COMPONENTS (MIRRORED) FIGURE 5. BOTTOM LAYER ETCH (MIRRORED) 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 AN1443.0 December 1, 2008