Application Note 1365 ISL8013AEVAL2Z: 3A Low Quiescent Current 1MHz High Efficiency Synchronous Buck Regulator Description Quick Setup Guide The ISL8013AEVAL2Z kit is intended for use by individuals with requirements for Point-of-Load applications sourcing from 2.7V to 5.5V. The ISL8013AEVAL2Z evaluation board is used to demonstrate the performance of the ISL8013A low quiescent current mode converter. The ISL8013A is offered in a 4mmx4mm 16 Ld QFN package with 1mm maximum height. The complete converter occupies less than 0.4in2 area. The ISL8014A is pin-to-pin compatible with the ISL8013A. Key Features • High Efficiency Synchronous Buck Regulator with up to 95% Efficiency • Power-Good (PG) Output with 1ms Delay 1. Ensure that the circuit is correctly connected to the supply and loads prior to applying any power. 2. Connect the bias supply to VIN. Plus terminal to P4 (VIN) and negative return to P5 (GND). 3. Verify that position is ON for SW1. 4. Turn on the power supply. 5. Verify the output voltage is 1.8V for VOUT Evaluating the Other Output Voltage The ISL8013AEVAL2Z kit output is preset to 1.8V; however, output voltages can be adjusted from 0.8V to 3.3V using Equations 1 and 2: R 1⎞ ⎛ V OUT = 0.8 ⎜ 1 + -------⎟ R 2⎠ ⎝ • 2.7V to 5.5V Supply Voltage Let’s set R1 = 124kΩ • 3% Output Accuracy Over-Temperature/Load/Line ( R1 ) R 2 = ------------------------------V OUT ⎛ ----------------⎞ – 1 ⎝ 0.8 ⎠ • 3A Guaranteed Output Current • Start-up with Pre-biased Output • Internal Digital Soft-Start - 1ms • Soft-Stop Output Discharge During Disabled (EQ. 1) (EQ. 2) Note: If desired output is 0.8V, then short R1 and open R2. • 35µA Quiescent Supply Current in PFM Mode Mode Control • Selectable Forced PWM Mode and PFM Mode The ISL8013A has a SKIP pin that controls the operation mode. When the SKIP pin is driven to low or shorted to ground, the regulator operates in a PFM mode. Set SKIP pin high forced PWM mode. The controller remains in the fixed PWM frequency at light load instead of entering the skip mode. In an application where a situation requires the ISL8013A regulator to sink more than 2A valley inductor current, it is recommended to operate in PFM to avoid any possible over stress. • External Synchronization up to 4MHz • Less than 1µA Logic Controlled Shutdown Current • 100% Maximum Duty Cycle for Lowest Dropout • Internal Current Mode Compensation • Peak Current Limiting and Hiccup Mode Short Circuit Protection • Over-Temperature Protection TABLE 1. SWITCH 1 SETTINGS Recommended Equipment The following materials are recommended to perform testing: • 0V to 10V Power Supply with at least 5A source current capability or 5V battery • Electronic Loads capable of sinking current up to 5A • Digital Multimeters (DMMs) • 100MHz quad-trace oscilloscope SW1 ENABLE ON/OFF CONTROL 1 OFF Disable VOUT 3 ON Enable VOUT SW2 SKIP FUNCTION 1 PWM Fixed PWM frequency at light load 3 PFM Force continuous mode • Signal generator December 16, 2009 AN1365.3 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. 2007, 2008, 2009. All Rights Reserved All other trademarks mentioned are the property of their respective owners. Application Note 1365 ISL8013AEVAL2Z Schematic J1 16 15 14 NC LX P4 P5 VIN 1 1 VIN 2 1 1 C1 22µF C2 22µF 2 2 1 2 R10 1 2 4 3 2 A L1 1.5µH LX LX 12 2 11 PG FB 5 6 7 8 R2 100k VIN 1 R5 2k 1 2 SYNCH P2 D1 PG 1 2 R7 100k 2N7002 Q1 3 SW2 1 21 31 VIN A R6 100k 2 1 P8 2 2 P3 1 2 2 A VIN 1 C6 22µF A NC A R4 100k C5 22µF 9 SGND EN P7 1 2 1 A 2 1 C4 47pF R1 124k U1 10 VDD ISL8013AIRZ SGND A 1 VOUT 1 PGND 4 SYNCH SYNCH EP 17 1 J2 13 PGND VIN 3 1 C3 OPEN LX 1 2 4 3 1 PWM 1 P6 ON OFF 1 2 2 R9 OPEN A 3 SW1 1 PFM R8 OPEN 1 1 2 2 EN A A NOTE: Pin 16 is a no connect pin which can tie to VIN, SGND, or LX 2 AN1365.3 December 16, 2009 Application Note 1365 ISL8013AEVAL2Z Bill of Materials PART NUMBER REFERENCE QTY DESIGNATOR ISL8013AEVAL2Z 1 H1045-00470-50V5-T 1 H1045-DNP 0 H1065-00226-6R3V10-T 4 DESCRIPTION MANUFACTURER PWB-PCB, ISL8013AEVAL2Z, REVA, ROHS C4 C3 CAP, SMD, 0603, 47pF, 50V, 5%, NPO, ROHS 1 L1 131-4353-00 2 J1, J2 1514-2 4 5002 LTST-C170CKT ISL8013AEVAL2ZREVAPCB AVX 06035A470JAT2A PHILLIPS 0603X7R500-562KNE MURATA GRM31CR60J226KE19L KEMET C1206C226K9PACTU AVX 12066D226KAT2A COOPER ELECTRONIC TECH. DR73-1R5-R CAP, SMD, 0603, DNP-PLACE HOLDER, ROHS C1, C2, C5, C6 CAP, SMD, 1206, 22µF, 6.3V, 10%, X5R, ROHS DR73-1R5-R MANUFACTURER PART COIL-PWR INDUCTOR, SMD, 7.5mm, 1.5µH, 20%, 6.52A, ROHS CONN-SCOPE PROBE TEST PT, TEKTRONIX COMPACT, PCB MNT, ROHS 131-4353-00 P4, P5, P7, P8 CONN-TURRET, TERMINAL POST, TH, ROHS KEYSTONE 1514-2 3 P2, P3, P6 CONN-MINI TEST POINT, VERTICAL, WHITE, ROHS KEYSTONE 5002 1 D1 LED-GaAs RED, SMD, 2mmx1.25mm, 100mW, 40mA, 10mcd, ROHS LITEON/VISHAY LTST-C170CKT ROHM SML-210LTT86 STANLEY ELECTRIC BR112H-TR ISL8013AIRZ 1 U1 IC-3A, 1MHz, BUCK REGULATOR, 16P, QFN, 4x4, ROHS INTERSIL ISL8013AIRZ 2N7002-7-F-T 1 Q1 TRANSISTOR, N-CHANNEL, 3LD, SOT-23, 60V, 115mA, ROHS DIODES, INC. 2N7002-7-F H2511-00R00-1/10W-T 1 H2511-01003-1/10W1-T 4 H2511-01243-1/10W1-T 1 H2511-02001-1/10W1-T R10 ON SEMICONDUCTOR 2N7002LT1G RESISTOR, SMD, 0603, 0Ω, 1/10W, TF, ROHS R2, R4, R6, R7 RES, SMD, 0603, 100k, 1/10W, 1%, TF, ROHS R1 1 R5 H2511-DNP 0 R8, R9 GT11MSCBE-T 2 SW1, SW2 LABEL-SERIAL NUMBER 1 RES, SMD, 0603, 124k, 1/10W, YAGEO 1%, TF, ROHS PANASONIC RES, SMD, 0603, 2k, 1/10W, 1%, TF, ROHS 9C06031A1243FKHFT ERJ-3EK1243V KOA RK73H1JTTD2001F VENKEL CR0603-10W-2001FT C&K COMPONENTS GT11MSCKE RES, SMD, 0603, DNP-PLACE HOLDER, ROHS SWITCH-TOGGLE, SMD, ULTRAMINI, 1P, SPST MINI LABEL, FOR SERIAL NUMBER AND BOM REV # 3 AN1365.3 December 16, 2009 Application Note 1365 ISL8013AEVAL2Z Board Layout ISL8013AEVAL2Z FIGURE 1. TOP COMPONENTS FIGURE 2. TOP LAYER ETCH 4 AN1365.3 December 16, 2009 Application Note 1365 ISL8013AEVAL2Z Board Layout (Continued) FIGURE 3. 2ND LAYER ETCH FIGURE 4. 3RD LAYER ETCH 5 AN1365.3 December 16, 2009 Application Note 1365 ISL8013AEVAL2Z Board Layout (Continued) FIGURE 5. BOTTOM LAYER COMPONENTS (MIRRORS) FIGURE 6. BOTTOM LAYER ETCH (MIRROR) 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 AN1365.3 December 16, 2009