USERS MANUAL ISL85410DEMO1Z, ISL854102DEMO1Z, ISL85418DEMO1Z AN1908 Rev.3.00 Demonstration Boards User Guide Nov 18, 2016 Description Key Features The ISL85410DEMO1Z, ISL854102DEMO1Z, and Wide input voltage range 3V to 40V ISL85418DEMO1Z boards are intended for use in point-of-load Synchronous operation for high efficiency applications sourcing from 3V to 40V. The boards are used to No compensation required demonstrate the performance of the ISL85410, ISL854102, and ISL85418 wide V , low quiescent current, high-efficiency Integrated high-side and low-side NMOS devices IN synchronous buck regulators with 1A (ISL85410), 1.2A Selectable PFM or forced PWM mode at light loads (ISL854102), and 800mA (ISL85418) output current. Internal fixed (500kHz) or adjustable switching frequency The ISL85410, ISL854102, and ISL85418 are offered in a 300kHz to 2MHz 4mmx3mm 12 Ld DFN package with 1mm maximum height. Continuous output current up to 1A (ISL85410), 1.2A 2 The converter occupies 1.516cm area. (ISL854102) and 800mA (ISL85418) Internal or external soft-start Key Specifications Minimal external components required These boards have been configured and optimized for the Power-good and enable functions available following operating conditions: V = 24V IN Related Literature V = 3.3V OUT For a full list of related documents, visit our website I = 1A (ISL85410), 1.2A (ISL854102), and MAX - ISL85410, ISL854102, and ISL85418 product pages 800mA (ISL85418) f = 500kHz SW Ordering Information Peak efficiency: >84% at 50% load PART NUMBER DESCRIPTION Output ripple: <10mV at 1.2A ISL85410DEMO1Z Demonstration Board (1A output current) Dynamic response: 4.5% ISL854102DEMO1Z Demonstration Board (1.2A output current) - 0A to 1.2A and 1.2A to 0A steps, PWM, di/dt = 1A/s) ISL85418DEMO1Z Demonstration Board (800mA output current) Board temperature: +25C 66 )6 SYNC 6<1& &203 %227 ISL85410 )% ISL854102 VIN ISL85418 9,1 9&& VOUT PG 3+ 6( 3* EN 3*1 (1 FIGURE 1. BLOCK DIAGRAM AN1908 Rev.3.00 Page 1 of 14 Nov 18, 2016Demonstration Boards User Guide ISL85410DEMO1Z, ISL854102DEMO1Z, ISL85418DEMO1Z Frequency Control Recommended Equipment The ISL85410, ISL854102, and ISL85418 have an FS pin that The following materials are recommended to perform testing: controls the frequency of operation. Programmable frequency 0V to 50V power supply with at least 2A source current allows for optimization between efficiency and external capability component size. It also allows low frequency operation for low V s when minimum on-time would limit the operation OUT Electronic loads capable of sinking current up to 2A otherwise. Default switching frequency is 500kHz when FS is tied Digital Multimeters (DMMs) to VCC (R = 0). By removing R , the switching frequency can 10 10 100MHz quad-trace oscilloscope be changed from 300kHz (R = 340k) to 2MHz (R = 32.4k). 12 12 Please refer to datasheets ISL85410, ISL854102 and ISL85418 for Signal generator calculating the value of R . Do not leave this pin floating. 10 Quick Setup Guide SYNC Control 1. Ensure that the circuit is correctly connected to the supply and The ISL85410, ISL854102, and ISL85418 demo boards have a loads prior to applying any power. SYNC pin that allows external synchronization frequency to be = 200k to V , which applied. Default board configuration has R 2. Connect the bias supply to VIN, the plus terminal to VIN (P4) 6 CC defaults to PWM operation mode and also to the preselected and the negative return to GND (P5). switching frequency set by R (see datasheet and previous 12 3. Turn on the power supply. section Frequency Control for details). If this pin is tied to GND, 4. Verify the output voltage is 3.3V for V . the IC will operate in PFM mode. The S2 switch allows forced OUT PFM or PWM modes. Evaluating the Other Output Voltage Soft-Start/COMP Control The ISL85410DEMO1Z, ISL854102DEMO1Z, and ISL85418DEMO1Z board outputs are preset to 3.3V however, R selects between internal (R = 0) and external soft-start. 15 15 output voltages can be adjusted from 0.6V to 15V. The output R selects between internal (R = 0) and external 11 11 , will depend on the desired voltage programming resistor, R compensation. For applications where repetitive restarts of the 2 output voltage of the regulator and the value of the feedback IC are required, it is recommended to add a 350k resistor in resistor R , as shown in Equation 1. 1 parallel to CSS in order to allow its fast discharge. Please refer to 0.6 Pin Description Table of the ISL85410, ISL854102 and ISL85418 ------------------------------ R = R (EQ. 1) 2 1 V 0.6 datasheets. OUT If the output voltage desired is 0.6V, then R is shorted. Please 1 note that if V is less than 1.8V, the switching frequency and OUT compensation must be changed for 300kHz operation due to minimum on-time limitation. Please refer to datasheets ISL85410, ISL854102 and ISL85418 for further information. Table 1 shows the component selection that should be used for the respective V . OUT TABLE 1. EXTERNAL COMPONENT SELECTION V +C L C R R C R R C OUT 1 5 6 1 2 4 12 3 7 (V) (H) (F) (k ) (k ) (pF) (k ) (k ) (pF) 12 22 2x22 90.9 4.75 22 115 150 470 5 22 47+22 90.9 12.4 27 DNP 100 470 (Note 1) 3.3 22 47+22 90.9 20 27 DNP 100 470 (Note 1) 2.5 22 47+22 90.9 28.7 27 DNP 100 470 (Note 1) 1.8 12 47+22 90.9 45.5 27 DNP 70 470 (Note 1) NOTE: 1. Connect FS to VCC. AN1908 Rev.3.00 Page 2 of 14 Nov 18, 2016