Application Note 1930 ISL85003EVAL2Z, ISL85003AEVAL2Z Evaluation Board User Guide Description Key Board Features The ISL85003 and ISL85003A kits are intended for use for point-of-load applications sourcing from 4.5V to 18V. The kits are used to demonstrate the performance of the ISL85003 and ISL85003A, low quiescent current high efficiency synchronous buck regulators. • Small, compact design • Switch selectable EN (enabled/disabled) • Switch selectable MODE (auto-DCM/forced-PWM) • Connectors and test points for easy probing The ISL85003 and ISL85003A are offered in a 4x3mm dual flat no lead (DFN) package. References Specifications • ISL85003, ISL85003A datasheet The boards are designed to operate at the following operating conditions: Ordering Information • Input voltage range from 4.5V to 18V PART NUMBER • Resistor programmable output voltage from 0.8V, ±1% • Up to 3A output current • Current mode control - DCM/CCM - Internal or external compensation options - 500kHz switching frequency option - External synchronization up to 2MHz on ISL85003 ISL85003EVAL2Z Evaluation Board for ISL85003FRZ and ISL85003AFRZ Evaluating the Other Output Voltage • Adjustable soft-start time on the ISL85003A • Operating junction temperature range: -40°C to +125°C Quick Setup Guide 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, the plus terminal to VIN (P4) and the negative return to PGND (P5). 3. Connect the output load to V0, the plus terminal to V0 (P8) and the negative return to PGND (P9). 4. Verify that the position is PWM or PFM for SW2. The ISL85003 and ISL85003A kit outputs are preset to 5V for VOUT; however, the output voltages are programmed using an external resistor divider that scales the feedback relative to the internal reference voltage. The output voltage programming resistor, R2, will depend on the value chosen for the feedback resistor, R1, and the desired regulator output voltage, VOUT . The value for the feedback resistor R1 is typically between 10kΩ and 400kΩ as shown in Equation 1. R 1 0.8V R 2 = ------------------------------V OUT – 0.8V (EQ. 1) If the output voltage desired is 0.8V, then R2 is left unpopulated. R1 is still required to set the low frequency pole of the modulator compensation. Switch Control 5. Verify that the position is ON for SW1. The ISL85003 and ISL85003A evaluation boards contain SW1 and SW2 for various controls of the ISL85003 and ISL85003A circuitries. Table 1 details this function. 6. Turn on the power supply. 7. Verify the output voltage is 5V for VO. TABLE 1. SWITCH SETTINGS Recommended Equipment The following materials are recommended to perform testing: • 0V to 25V power supply with at least 10A source current capability • Electronic loads capable of sinking current up to 7A DESCRIPTION SW1 ENABLE FUNCTION 1 OFF Disable V0 3 ON Enable V0 SW2 MODE • Digital multimeters (DMMs) FUNCTION 1 DCM Force DCM • 100MHz quad-trace oscilloscope 3 PWM Fixed PWM frequency at light load • Signal generator August 28, 2014 AN1930.1 1 CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2014. All Rights Reserved Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries. All other trademarks mentioned are the property of their respective owners. Application Note 1930 Components Selection VOUT 0.8V 1V 1.2V 1.5V 1.8V 2.5V 3.3V 5V C1, C2 10µF 10µF 10µF 10µF 10µF 10µF 10µF 10µF C5 22µF 22µF 22µF 47µF 47µF 47µF 47µF 47µF C6 22µF 22µF 22µF 22µF 22µF 22µF 22µF 22µF C4 Open Open Open 4.7pF 4.7pF 4.7pF 4.7pF 4.7pF L1 1.8µH 2.2µH 2.2µH 3.3µH 3.3µH 3.3µH 4.7µH 4.7µH R1 301kΩ 301kΩ 301kΩ 301kΩ 301kΩ 301kΩ 301kΩ 301kΩ R2 Open 1.2MΩ 604kΩ 344kΩ 241kΩ 142kΩ 96.3kΩ 57.6kΩ NOTE: VIN = 12V, IOUT = 3A; The components selection table is a suggestion for typical application using internal compensation mode. For applications that require high output capacitance greater than 200µF, R1 should be adjusted to maintain a loop response bandwidth about 40kHz. ISL85003EVAL2Z Evaluation Board FIGURE 1. TOP VIEW Submit Document Feedback 2 FIGURE 2. BOTTOM VIEW AN1930.1 August 28, 2014 Submit Document Feedback ISL85003EVAL2Z Rev B Schematic D2 VOUT U1 VOUT SYNC 1 PG 2 EN 3 SYNC BOOT PG VDD 12 DNP 11 VCC P7 3 VCC R4 20 EN VIN ISL85003 4 VIN C3 0.1uF 9 DNP 5 DNP C4 C8 R11 0 6 COMP PHASE AGND PHASE EPAD 301k GND P8 7 4.7uH VOUT C5 47uF 13 R2 57.1k D1 LTST-C190KGKT AN1930.1 August 28, 2014 Q1 2N7002 2 VIN R6 200k SYNC SW2 PWM SYNC R9 DNP DCM R7 200k P6 ENABLE SW1 ON EN R8 DNP P9 GND 1 J1 2 J2 VCC P2 C6 22uF VOUT PHASE R5 2k VIN P5 L1 DNP VCC PG + C10 150uF C2 10uF 8 1 P1 C1 10uF OFF Application Note 1930 R3 R14 200k C9 1uF C7 R1 4.7p FB P4 10 Application Note 1930 Bill of Materials PART NUMBER QTY UNITS REFERENCE DESIGNATOR DESCRIPTION MFR INTERSIL MFR PART # ISL85003FRZ 1 ea U1 IC-3A BUCK REGULATOR, 12P, DFN, 4X3, ROHS ISL85003AFRZ 1 ea U1 IC-3A BUCK REGULATOR PWM, 12P, DFN, 4X3, INTERSIL ROHS ISL85003AFRZ EEE-FK1H151P-T 1 ea C10 CAP, SMD, 10.3mm, 150µF, 50V, 20%, ROHS, PANASONIC ALUM.ELEC. EEE-FK1H151P H1044-004R7-50VR25-T 1 ea C4 CAP, SMD, 0402, 4.7pF, 50V, 0.25pF, NPO, ROHS GRM36COG4R7C050AQ H1044-DNP 0 ea C7, C8, CSS H1045-00104-50V10-T 1 ea C3 CAP, SMD, 0603, 0.1µF, 50V, 10%, X7R, ROHS AVX 06035C104KAT2A H1045-00105-16V10-T 1 ea C9 CAP, SMD, 0603, 1µF, 16V, 10%, X5R, ROHS GRM188R61C105KA12D H1065-00106-25V10-T 2 ea C1, C2 CAP, SMD, 1206, 10µF, 25V, 10%, X7R, ROHS VENKEL C1206X7R250-106KNE H1065-00226-25V10-T 2 ea C5, C6 CAP, SMD, 1206, 22µF, 25V, 10%, X5R, ROHS MURATA GRM31CR61E226KE15L RLF7030T-4R7M3R4 1 ea L1 COIL-PWR INDUCTOR, SMD, 7.3X6.8mm, 4.7µH, 20%, 3.5A, ROHS RLF7030T-4R7M3R4 131-4353-00 2 ea J1, J2 1514-2 4 ea P4, P5, P8, P9 CONN-TURRET, TERMINAL POST, TH, ROHS KEYSTONE 1514-2 5002 4 ea P1, P2, P6, P7 CONN-MINI TEST POINT, VERTICAL, WHITE, ROHS KEYSTONE 5002 BAT54C-T 1 ea D2 DIODE-RECTIFIER, SMD, SOT23, 3P, 30V, 200mA, ROHS FAIRCHILD BAT54C LTST-C190KGKT-T 1 ea D1 LED, SMD, 0603, GREEN CLEAR, 2V, 20mA, 571nm, 35mcd, ROHS LITEON/VISHAY LTST-C190KGKT 2N7002LT1G-T 1 ea Q1 TRANSISTOR-MOS, N-CHANNEL, SMD, SOT23, ON 60V, 115mA, ROHS SEMICONDUCTOR 2N7002LT1G H2510-00R00-1/16W-T 1 ea R11 RES, SMD, 0402, 0Ω, 1/16W, 5%, TF, ROHS CR0402-16W-00T H2510-03013-1/16W1-T 1 ea R1 RES, SMD, 0402, 301k, 1/16W, 1%, TF, ROHS YAGEO RC0402FR-07301KL H2510-05762-1/16W1-T 1 ea R2 RES, SMD, 0402, 57.6k, 1/16W, 1%, TF, ROHS PANASONIC ERJ-2RKF5762X H2510-DNP 0 ea R3 RES, SMD, 0402, DNP, DNP, DNP, TF, ROHS H2511-00200-1/10W1-T 1 ea R4 RES, SMD, 0603, 20Ω, 1/10W, 1%, TF, ROHS PANASONIC ERJ-3EKF20R0V H2511-02001-1/10W1-T 1 ea R5 RES, SMD, 0603, 2k, 1/10W, 1%, TF, ROHS RK73H1JTTD2001F H2511-02003-1/10W1-T 3 ea R6, R7, R14 H2511-DNP 0 ea R8, R9 GT11MSCBE-T 2 ea SW1, SW2 SWITCH-TOGGLE, SMD, 6PIN, SPDT, 2POS, ON- ITT INDUSTRIES/ ON, ROHS C&K DIVISION GT11MSCBE SJ-5003-BLACK 4 ea Bottom four corners BUMPONS, 0.44inW x 0.20inH, DOMETOP, BLACK SJ-5003SPBL MURATA ISL85003FRZ CAP, SMD, 0402, DNP-PLACE HOLDER, ROHS MURATA TDK CONN-SCOPE PROBE TEST PT, COMPACT, PCB TEKTRONIX MNT, ROHS VENKEL KOA RES, SMD, 0603, 200k, 1/10W, 1%, TF, ROHS VENKEL 131-4353-00 CR0603-10W-2003FT RES, SMD, 0603, DNP-PLACE HOLDER, ROHS 3M 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 Submit Document Feedback 4 AN1930.1 August 28, 2014 Application Note 1930 PCB Layout FIGURE 3. TOP LAYER FIGURE 4. INNER LAYER 1 FIGURE 5. INNER LAYER 2 FIGURE 6. BOTTOM LAYER Submit Document Feedback 5 AN1930.1 August 28, 2014