USERS MANUAL ISL6238xxxEVAL1Z AN1396 Rev 0.00 ISL62381, ISL62382 Quad-Output Evaluation Board User Guide July 31, 2008 . The ISL62381 and ISL62382 evaluation boards demonstrate TABLE 2. ENABLE TRUTH TABLE the performance of ISL62381 and ISL62382 Quad-output EN1 EN2 START-UP SEQUENCE controllers. The ISL62381 and ISL62382 controller include Low Low Both Channel outputs OFF simultaneously two pulse-width modulation (PWM) controllers featured with 3 Intersils patented R technology, adjustable from 0.6V to Low Float Both Channel outputs OFF simultaneously 5.5V, and two linear regulators, LDO5 and LDO3, that Float Low Both Channel outputs OFF simultaneously generate a fixed 5V and an adjustable output respectively. Float Float Both Channel outputs OFF simultaneously The evaluation board includes two independent Enable Low High Channel-1 OFF, Channel-2 ON switches, two LED Power-Good indicators and various test High Low Channel-1 ON, Channel-2 OFF points. Included with each switching channel is an on-board dynamic load generator for evaluating the transient-load High High Both Channel outputs ON simultaneously response. There are four different evaluation boards which Float High Channel-1 enabled after Channel-2 is in regulation provide flexible evaluation options. Table 1 shows a brief High Float Channel-2 enabled after Channel-1 is in regulation description of the evaluation boards. TABLE 1. EVALUATION BOARD DESCRIPTION Resistor Current Sense Configuration EVALUATION BOARD CHANNEL-1 CHANNEL-2 OCP The evaluation board is pre-configured with inductor DCR ISL62381LOEVAL1Z 3.3V/8A 5V/8A ~10A current sense. For more precise overcurrent protection, it also provides the option of resistor current sense. Figure 1 ISL62381HIEVAL1Z 1.05V/15A 1.5V/15A ~20A shows the configuration for resistor current sense. ISL62382LOEVAL1Z 3.3V/8A 5V/8A ~10A L R SENSE I L V O ISL62382HIEVAL1Z 1.05V/15A 1.5V/15A ~20A PHASEx + V RSENSE Whats Inside ISL62381 C O ISL62382 The Evaluation Board Kit contains the following materials: 10A R OCSET OCSETx ISL6238xxxEVAL1Z Evaluation Board + V R ROCSET O ISL62381 and ISL62382 Datasheet ISENx ISL62381 And ISL62382 Evaluation Board User Guide (this document) FIGURE 1. RESISTOR CURRENT SENSE CIRCUIT Whats Needed For Channel-1, the ISL62381 and ISL62382 monitors the The following materials will be needed to perform testing: OCSET1 pin and the ISEN1 pin voltages. Once the OCSET1 pin voltage is higher than the ISEN1 pin voltage for more than Adjustable +25V, 30A Power Supply 10s, the ISL62381 and ISL62382 declare an overcurrent +12V, 100mA Power Supply fault. For a chosen overcurrent, set point I and current OC sense resistor R , the value of R is determined SENSE OCSET Precision digital multi-meter by Equation 1 4 Electronic Loads I R OC SENSE R = ------------------------------------- 4-Channel Oscilloscope OCSET (EQ. 1) 10 A Enable Control Where: The evaluation board provides flexible control logic to enable -R () is the resistor used to program the OCSET or disable the outputs, and to program the two PWM overcurrent setpoint channels start-up sequence. For start-up timing sequence, -I is the output current threshold that will activate the OC please refer to the datasheet waveforms. Table 2 is the OCP circuit Enable controller truth table. -R is current sense resistor (R for Channel-1 and SENSE 3 R for Channel-2) 25 AN1396 Rev 0.00 Page 1 of 14 July 31, 2008ISL6238xxxEVAL1Z Take Channel-1 as an example, once the value of R Dynamic Load Generator OCSET is calculated, follow the following procedure to configure the The evaluation board provides each PWM channel an resistor current sense circuit: on-board dynamic load generator for evaluating the transient-load response, which are controlled by SW1 and Step 1: Open the DCR SENSE solder bridge and connect the RESISTOR SENSE solder bridge SW2 respectively. The dynamic load generator applies a on the PCB bottom layer 300s pulse load across V and GND. The transient load OUT slew-rate can be trimmed by adjusting the resistors R , R Step 2: Remove R (R for Channel 2) 34 40 7 22 for the rising edge, and R , R for the falling edge. +12V 38 39 Step 3: Replace R (R for Channel 2) with R 3 25 SENSE power supply is needed to power the dynamic load Step 4: Replace C (C for Channel 2) with R 6 25 OCSET generator. Step 5: Replace replace R (R for Channel 2) with 19 18 R OCSET. Connections and Test Points The following table describes the function and operation of the evaluation boards. NUMBER NAME FUNCTION/OPERATION INTERFACES AND CONNECTIONS TP3 VBAT V positive power input IN TP4 GND V return power input IN TP1 VOUT1 Channel-1 positive power output TP2 GND Channel-1 return power output TP11 VOUT2 Channel-2 positive power output TP12 GND Channel-2 return power output TP20 +12V +12V positive power input, used for the power supply of the on-board dynamic-load generator TP19 GND +12V return power input TEST POINTS J1 PHASE2 Scope-probe socket for measuring Channel-2 phase node J3 PHASE1 Scope-probe socket for measuring Channel-1 phase node J2 VOUT1 Scope-probe socket for measuring Channel-1 output J5 VOUT2 Scope-probe socket for measuring Channel-2 output J4 FLOAT FCCM Remove the jumper will float the FCCM pin J6 FLOAT EN1 Remove the jumper will float the EN1 pin J7 FLOAT EN2 Remove the jumper will float the EN2 pin TP17 EN1 Test point of EN1 pin TP8 EN2 Test point of EN2 pin TP9 LDO3EN Test point of LDO3EN pin TP10 FCCM Test point of FCCM pin POWER-GOOD INDICATORS TP13 PGOOD1 Test point of PGOOD1 pin TP5 PGOOD2 Test point of PGOOD2 pin D1 Channel-1 Power-Good indicator. Green when VOUT1 is in regulation. D2 Channel-2 Power-Good indicator. Green when VOUT2 is in regulation. LINEAR REGULATORS TP14 LDO5 LDO5 linear regulator positive power output TP15 GND LDO5 linear regulator return power output TP16 LDO3IN Input of LDO3 linear regulator. Connect to connected to a voltage greater than the LDO3 set point plus the dropout voltage. TP18 LDO3FB LDO3 linear regulator output voltage feedback test point TP6 LDO3 LDO3 linear regulator positive power output TP7 GND LDO3 linear regulator return power output AN1396 Rev 0.00 Page 2 of 14 July 31, 2008