Intersil ISL62381 Manuals

1 ® ISL62381, ISL62382 Quad-Output Evaluation Board User Guide Introduction The ISL62381 and ISL62382 evaluation boards demonstrate the performance of ISL62381 and ISL62382 Quad-output controllers. The ISL62381 and ISL62382 controller include two pulse-width modulation (PWM) controllers featured with Intersil’s patented R3 technology, adjustable from 0.6V to 5.5V, and two linear regulators, LDO5 and LDO3, that generate a fixed 5V and an adjustable output respectively. The evaluation board includes two independent Enable switches, two LED Power-Good indicators and various test points. Included with each switching channel is an on-board dynamic load generator for evaluating the transient-load response. There are four different evaluation boards which provide flexible evaluation options. Table 1 shows a brief description of the evaluation boards. What’s Inside The Evaluation Board Kit contains the following materials: • ISL6238xxxEVAL1Z Evaluation Board • ISL62381 and ISL62382 Datasheet • ISL62381 And ISL62382 Evaluation Board User Guide (this document) What’s Needed The following materials will be needed to perform testing: • Adjustable +25V, 30A Power Supply • +12V, 100mA Power Supply • Precision digital multi-meter • 4 Electronic Loads • 4-Channel Oscilloscope Enable Control The evaluation board provides flexible control logic to enable or disable the outputs, and to program the two PWM channels’ start-up sequence. For start-up timing sequence, please refer to the datasheet waveforms. Table 2 is the Enable controller truth table. . Resistor Current Sense Configuration The evaluation board is pre-configured with inductor DCR current sense. For more precise overcurrent protection, it also provides the option of resistor current sense. Figure 1 shows the configuration for resistor current sense. For Channel-1, the ISL62381 and ISL62382 monitors the OCSET1 pin and the ISEN1 pin voltages. Once the OCSET1 pin voltage is higher than the ISEN1 pin voltage for more than 10µs, the ISL62381 and ISL62382 declare an overcurrent fault. For a chosen overcurrent, set point IOC and current sense resistor RSENSE, the value of ROCSET is determined by Equation 1 Where: - ROCSET (Ω) is the resistor used to program the overcurrent setpoint - IOC is the output current threshold that will activate the OCP circuit - RSENSE is current sense resistor (R3 for Channel-1 and R25 for Channel-2) TABLE 1. EVALUATION BOARD DESCRIPTION EVALUATION BOARD CHANNEL-1 CHANNEL-2 OCP ISL62381LOEVAL1Z 3.3V/8A 5V/8A ~10A ISL62381HIEVAL1Z 1.05V/15A 1.5V/15A ~20A ISL62382LOEVAL1Z 3.3V/8A 5V/8A ~10A ISL62382HIEVAL1Z 1.05V/15A 1.5V/15A ~20A TABLE 2. ENABLE TRUTH TABLE EN1 EN2 START-UP SEQUENCE Low Low Both Channel outputs OFF simultaneously Low Float Both Channel outputs OFF simultaneously Float Low Both Channel outputs OFF simultaneously Float Float Both Channel outputs OFF simultaneously Low High Channel-1 OFF, Channel-2 ON High Low Channel-1 ON, Channel-2 OFF High High Both Channel outputs ON simultaneously Float High Channel-1 enabled after Channel-2 is in regulation High Float Channel-2 enabled after Channel-1 is in regulation FIGURE 1. RESISTOR CURRENT SENSE CIRCUIT PHASEx CO L VO OCSETx ISENx RO ISL62381 IL 10µA + _ VRSENSE + VROCSET _ RSENSE ROCSET ISL62382 (EQ. 1) ROCSET IOC RSENSE • 10μA ------------------------------------- = July 31, 2008 AN1396.0 Application Note 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.