Application Note 1366 ISL8014AEVAL2Z: 4A Low Quiescent Current 1MHz High Efficiency Synchronous Buck Regulator Description Quick Setup Guide The ISL8014AEVAL2Z kit is intended for use by individuals with requirements for Point-of-Load applications sourcing from 2.7V to 5.5V. The ISL8014AEVAL2Z evaluation board demonstrates the performance of the ISL8014A low quiescent current mode converter. The ISL8014A is offered in a 4mmx4mm 16 Ld QFN package with 1mm maximum height. The ISL8014A is pin-to-pin compatible to the ISL8013A. The complete converter occupies less than 0.4in2 area. Key Features • High Efficiency Synchronous Buck Regulator with up to 95% Efficiency • Power-Good (PG) Output with 1ms Delay • 2.7V to 5.5V Supply Voltage • 3% Output Accuracy Over-Temperature/Load/Line • 4A Guaranteed Output Current • Start-up with Pre-biased Output • Internal Digital Soft-Start - 1ms • Soft-Stop Output Discharge During Disabled • 35µA Quiescent Supply Current in PFM Mode • Selectable Forced PWM Mode and PFM Mode • 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 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 ISL8014AEVAL2Z 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⎠ ⎝ Let’s set R1 = 124kΩ ( R1 ) R 2 = ------------------------------V OUT ⎛ ----------------⎞ – 1 ⎝ 0.8 ⎠ (EQ. 2) Note: If desired output is 0.8V, then short R1 and open R2. Mode Control The ISL8014A 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 situations require the ISL8014A regulator to sink more than 2A valley inductor current, it is recommended to operate in PFM to avoid any possible over stress. • 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) (EQ. 1) 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 • 100MHz Quad-trace Oscilloscope • Signal Generator December 16, 2009 AN1366.3 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 1366 ISL8014AEVAL2Z Schematic J1 16 15 14 NC LX P4 VIN 1 VIN 2 1 1 C1 22µF C2 22µF 2 P5 1 1 2 R10 2 1 2 4 3 2 A L1 1.5µH LX NC 12 PG FB 5 6 7 8 R2 100k 1 R5 2k P2 D1 1 2 2N7002 Q1 R7 100k 1 2 SYNCH 3 SW2 1 21 31 VIN A R6 100k 2 PG P8 2 VIN 1 1 2 2 A 2 P3 C6 22µF A NC VIN 1 C5 22µF 9 SGND EN P7 1 2 1 A 2 C4 47pF R1 124k A R4 100k 1 2 11 U1 10 VDD ISL8014AIRZ 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: Pins 13 and 16 are no connect pins which can tie to VIN, SGND, or LX. Recommend connecting pin 13 to LX for compatibility to ISL8013. 2 AN1366.3 December 16, 2009 Application Note 1366 ISL8014AEVAL2Z Bill of Materials PART NUMBER REFERENCE QTY DESIGNATOR ISL8014AEVAL2Z 1 H1045-00470-50V5-T 1 H1045-DNP 0 H1065-00226-6R3V10-T 4 C4 C3 DESCRIPTION 1 L1 131-4353-00 2 J1, J2 1514-2 4 5002 3 P2, P3, P6 LTST-C170CKT 1 D1 MANUFACTURER PART PWB-PCB, ISL8014AEVAL2Z, REVA, ROHS ISL8014AEVAL2ZREVAPCB CAP, SMD, 0603, 47pF, 50V, 5%, AVX NPO, ROHS PHILLIPS 06035A470JAT2A 0603X7R500-562KNE CAP, SMD, 0603, DNP-PLACE HOLDER, ROHS C1, C2, C5, C6 CAP, SMD, 1206, 22µF, 6.3V, 10%, X5R, ROHS DR73-1R5-R MANUFACTURER MURATA GRM31CR60J226KE19L KEMET C1206C226K9PACTU AVX 12066D226KAT2A COIL-PWR INDUCTOR, SMD, 7.5mm, 1.5µH, 20%, 6.52A, ROHS COOPER ELECTRONIC DR73-1R5-R TECH. CONN-SCOPE PROBE TEST PT, COMPACT, PCB MNT, ROHS TEKTRONIX P4, P5, P7, P8 CONN-TURRET, TERMINAL POST, KEYSTONE TH, ROHS 131-4353-00 1514-2 CONN-MINI TEST POINT, VERTICAL, WHITE, ROHS KEYSTONE 5002 LED-GaAs RED, SMD, 2mmx1.25mm, 100mW, 40mA, 10mcd, ROHS LITEON/VISHAY LTST-C170CKT ROHM SML-210LTT86 STANLEY ELECTRIC BR112H-TR ISL8014AIRZ 1 U1 IC-4A, 1MHz, BUCK REGULATOR, INTERSIL 16P, QFN, 4x4, ROHS 2N7002-7-F-T 1 Q1 TRANSISTOR, N-CHANNEL, 3LD, DIODES, INC. 2N7002-7-F SOT-23, 60V, 115mA, ROHS ON SEMICONDUCTOR 2N7002LT1G H2511-00R00-1/10W-T 1 R10 RESISTOR, SMD, 0603, 0Ω, 1/10W, TF, ROHS H2511-01003-1/10W1-T 4 H2511-01243-1/10W1-T 1 H2511-02001-1/10W1-T ISL8014AIRZ 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, 1%, TF, ROHS YAGEO 9C06031A1243FKHFT PANASONIC ERJ-3EK1243V RES, SMD, 0603, 2k, 1/10W, 1%, KOA TF, ROHS VENKEL RK73H1JTTD2001F CR0603-10W-2001FT RES, SMD, 0603, DNP-PLACE HOLDER, ROHS SWITCH-TOGGLE, SMD, ULTRAMINI, 1P, SPST MINI C&K COMPONENTS GT11MSCKE LABEL, FOR SERIAL NUMBER AND BOM REV # 3 AN1366.3 December 16, 2009 Application Note 1366 ISL8014AEVAL2Z Board Layout ISL8014AEVAL2Z FIGURE 1. TOP COMPONENTS FIGURE 2. TOP LAYER ETCH 4 AN1366.3 December 16, 2009 Application Note 1366 ISL8014AEVAL2Z Board Layout (Continued) FIGURE 3. 2ND LAYER ETCH FIGURE 4. 3RD LAYER ETCH 5 AN1366.3 December 16, 2009 Application Note 1366 ISL8014AEVAL2Z 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 AN1366.3 December 16, 2009