Application Note 1953 ISL70002SEH Dual Phase Current Share Evaluation Board User Guide ISL70002SEHEVAL2Z Specifications The ISL70002SEHEVAL2Z evaluation board is designed to evaluate the performance of the ISL70002SEH in a dual regulator current sharing configuration. The ISL70002SEH is a TID and SEE hardened 12A synchronous buck regulator IC with integrated MOSFETs intended for space applications. For more detailed information, please refer to the datasheet ISL70002SEH. This board has been configured for the following operating conditions: The ISL70002SEHEVAL2Z evaluation board accepts an input voltage of 3V to 5.5V and provides a regulated default output voltage of 1.0V configured to current share to provide 19A total output current, assuming ±27% worst-case current share accuracy. The output can be quickly adjusted to an alternate voltage using the onboard potentiometer. A PGOOD (power-good) signal goes high and lights a green LED to indicate that the output voltage is within a ±11% typical regulation window. A toggle switch (SW1) is provided to conveniently enable or disable the regulators. The ISL70002SEHEVAL2Z evaluation board can be set to run from the nominal 500kHz or 1MHz internal oscillator of the master ISL70002SEH with the two devices synchronized 180° out-of-phase to reduce input RMS ripple current. FIGURE 1. TOP VIEW September 23, 2014 AN1953.0 1 • 96% peak efficiency at 3.3V VIN, 2.5V VOUT, 500kHz • 19A max current Key Features • Dual regulator current sharing solution • Dual-sided PCB References ISL70002SEH Datasheet Ordering Information PART NUMBER DESCRIPTION ISL70002SEHEVAL2Z ISL70002SEH Dual Phase Current Share FIGURE 2. BOTTOM VIEW 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 1953 What’s Inside ISL70002SEH block diagram of the current sharing configuration. The Evaluation Board Kit contains the following materials: • ISL70002SEHEVAL2Z Evaluation Board • ISL70002SEH Datasheet. • ISL70002SEH Dual Phase Current Share Evaluation Board User Guide Recommended Test Equipment • 0 to 6V power supply with at least 35A current capability • Electronic load capable of sinking current up to 21A • Digital multimeters (DMMs) • A 500MHz dual or quad trace oscilloscope • Frequency response analyzer (0.01Hz to 10MHz) Quick Start In this master/slave configuration the two ISL70002SEH ICs operate ~180° out-of-phase to minimize the input ripple current, effectively operating as a single IC at twice the switching frequency. The master phase uses the falling edge of the SYNC clock to initiate the master switching cycle with the nonoverlap period before the rising edge of LX, while the slave phase internally inverts the SYNC input and uses the falling edge of the inverted copy to start its switching cycle. This is independent of whether the master phase is configured for an external clock (master M/S = DGND) or its internal clock (master M/S = DVDD). The master error amplifier and compensation controls the two phase regulator while the slave error amplifier is disabled. The “ISL70002SEHEVAL2Z Schematic” on page 9 shows the complete configuration connection used on this evaluation platform for the Master and Slave IC. 3V TO 5.5V 1. Toggle S1 to the OFF position. 2. Turn on the power supply. Set the output voltage to 5V. Turn off the power supply. 3. Connect the positive lead of the power supply to VIN and the negative lead of the power supply to GND. HIGH ISL70002SEH #1 VOUT WITH UP TO 19A IOUT POWER LOAD ISL70002SEH #2 4. Ensure jumpers J30, J32, J27, J29, J13 and J18 are installed. This is the default shipping configuration. 5. Connect one DMM to monitor the input voltage from TP7 to TP14 and another DMM to monitor the output voltage from TP13 to TP11. 6. Connect oscilloscope to probe jacks LX and LXS to monitor the rectangular waveform on the LX pins of the master and slave ICs respectively. 7. Connect oscilloscope to probe jack VOUT to monitor the output voltage. Ripple voltage is customarily measured with 20MHz bandwidth limiting and AC coupling. 8. Turn on power supply and toggle S1 to the ON position. FIGURE 3. DUAL ISL70002SEH CURRENT SHARE BLOCK DIAGRAM Figure 4 shows the turn on of the ISL70002SEHEVAL2Z into a 0.1Ω load, the load sharing for the ~10A total load is ~44% for the master device and ~56% for the slave device. Figure 5 shows a transient load from 0A to 14A with a current sharing ratio of 45% to 55% for the master to slave respectively at max current. Both of these current sharing ratios are within the share guidance provided as worst case. 9. Verify the output voltage is 1.0V ±3% and the frequency of the LXx waveform is 500kHz ±10% . Evaluating ISL70002SEHEVAL2Z Dual Phase Current Share Operation Two ISL70002SEH devices are capable of operating as a single two-phase regulator with nearly twice the load current capacity. In this mode, a redundant current sharing bus balances the load current between the two devices and communicates any fault conditions. One ISL70002SEH is designated the master and the other the slave. The master ISHSL pin is connected to DGND and the slave ISHSL pin is connected to DVDD. The ISHEN pins on both master and slave are connected to DVDD. The SYNC, ISHA, ISHB, ISHC, ISHREFA, ISHREFB, ISHREFC, ISHCOM and FB pins are connected from the Master to the Slave and the REF pins are tied with a 10Ω resistor. Configured this way, the two-phase regulator nearly doubles the load current capacity, limited only by the current share match tolerance. See Figure 3 for an Submit Document Feedback 2 VOUT SLAVE CURRENT MASTER CURRENT FIGURE 4. DUAL ISL70002SEH SHARING UPON TURN-ON INTO 0.055Ω LOAD, VIN = 3.3V, VOUT = 1.0V, 1MHz AN1953.0 September 23, 2014 Application Note 1953 Changing the Turn-On Voltage The POR circuitry prevents the controller from attempting to soft-start before sufficient bias is present at the PVINx pins and is selectable on this evaluation board. The POR threshold is controlled by the PORSEL pin connection with J27. For a nominal 5V supply voltage, PORSEL should be connected to DVDD. For a nominal 3.3V supply voltage, PORSEL should be connected to DGND. For nominal supply voltages between 5V and 3.3V, PORSEL should be connected to DGND. SLAVE CURRENT MASTER CURRENT VOUT Slope Compensation FIGURE 5. DUAL ISL70002SEH SHARING of 0 TO 14A LOAD CURRENT TRANSIENT STEP, VIN = 3.3V, VOUT = 1.0V, 1MHz Loop Gain Measurements Loop measurement is needed to analyze the robustness of the power converter design. The evaluation board comes equipped with a resistor (R22) between the output voltage and the compensation network around the error amplifier, essentially breaking the loop and use test points TP9 and TP8 to inject the AC signal differentially across R22 (shorted by J32) and measure the loop response with the Frequency Response Analyzer. See Figures 26 and 27 for phase/gain plots. For more detailed information on loop measurement techniques refer to references [1] and [2]. Switching Frequency Selection The ISL70002SEH can operate at a 500kHz or a 1MHz nominal switching frequency. Jumper connector J29 labeled ‘FSEL’ is used to set the switching frequency for both the master and slave devices. Use Table 1 to configure the evaluation board to the desired switching frequency. TABLE 1. SETTINGS FOR CONNECTOR FSEL PINS CONDITION SWITCHING FREQUENCY (kHz) 1, 2 SHORT to GND 500 2, 3 SHORT to VIN 1000 Evaluating Other Output Voltages With a jumper installed on jumper J30, the ISL70002SEHEVAL2Z output voltage is preset to 1.0V. For quick evaluation of other output voltages, the ISL70002SEHEVAL2Z provides an on board potentiometer (R23) on the feedback network, as shown in Figure 4. To modify the output voltage through R23, flip SW1 to the OFF position. Open J30 and short J31. Enable the ISL70002SEH and measure the output voltage with a DMM. Use a small flat head screw driver to turn the potentiometer until the desired output voltage is achieved. Submit Document Feedback 3 The SC0 (J18) and SC1 (J31) pins select four levels of current mode slope compensation. In current mode buck regulators, when the duty cycle approaches and exceeds 50%, the regulator will operate in subharmonic oscillation without slope compensation. Slope compensation is widely considered unnecessary if the duty cycle is held below 40% and provides better phase margin. Transient duty cycles must be taken into consideration when selecting the level of slope compensation. Table 2 describes the amount of effective current that is added to the output power stage signal that is used in the PWM modulator. TABLE 2. FSEL SC1 SC0 SLOPE COMP (A/µs) DGND DGND DGND 0.8 DGND DGND DVDD 1.6 DGND DVDD DGND 3.3 DGND DVDD DVDD 6.6 DVDD DGND DGND 1.7 DVDD DGND DVDD 3.4 DVDD DVDD DGND 6.7 DVDD DVDD DVDD 13.4 ISL70002SEHEVAL2Z Efficiency Testing This dual current share application board is design with ISL70002SEH devices on both the top and bottom of the PCB. Because of this, the typical lab test methods of ambient air temperature control were unsuitable. In this instance we used calibrated temperature baths filled with electrically inert fluids to provide the ambient temperature the boards and ICs were exposed to. The immersion in a constantly swirling liquid controlled to within 0.1°C, makes it reasonable to assume that the ISL70002SEH case temperature is equal to the liquid’s controlled temperature. The power efficiency curves (Figures 6 through 25) were all produced using this best case thermal test condition method. This testing presents the efficiency curves with a known case temperature making the Si junction temperature calculation simpler and more robust. Testing with typical ambient air temperature control methods will result in lower efficiency. AN1953.0 September 23, 2014 Application Note 1953 Schematic and BOM A schematic and BOM of the ISL70002SEHEVAL2Z evaluation board are shown on page 9 and page 10, respectively. The schematic indicates the test points, which allow many nodes of the evaluation circuit to be monitored directly. The BOM shows components that are representative of the types needed for a design, but these components are not space qualified. Equivalent space qualified components would be required for flight applications. Layout Guidelines Layout is very important in high frequency switching converter design, particularly in a dual PWM IC configuration such as the ISL70002EVAL2Z. The resulting current transitions from one power device to another and causes voltage spikes across the interconnecting impedances and parasitic circuit elements. These voltage spikes can degrade efficiency, radiate noise into the circuit, and lead to device overvoltage stress. Careful component layout and printed circuit board design minimizes these voltage spikes. The following generic guidelines can be used: 1. Use an eight layer PCB with 2 ounce (70µm) copper or equivalent in thinner layers. 2. 2 layers should be dedicated for ground plane. 3. Top and bottom layers are used primarily for the ICs and signals, but can also be used to increase the VIN, VOUT and ground planes as required. 4. Connect all AGND, DGND and PGNDx pins directly to the ground plane. Connect all PVINx pins directly to the VIN portion of the power plane. 5. Locate ceramic bypass capacitors as close as possible to the PWM ICs. Prioritize the placement of the bypass capacitors on the pins of ICs in the order shown: PVINx, REF, AVDD, DVDD, SS, EN, PGOOD. 6. Locate the output voltage resistive divider as close as possible to the FB pin of the IC. The top leg of the divider should connect directly to the load and the bottom leg of the resistive divider should connect directly to AGND. The junction of the resistive divider should connect directly to the FB pin. 7. Use a small island of copper to connect the LXx pins of the regulator to the inductor, to minimize the routing capacitance that degrades efficiency. Separate the island from ground and power planes as much as possible. 8. Keep all signal traces as short as possible. 9. A small series snubber (R25 and C20) connected from the LXx pins to the PGNDx pins may be used to dampen ringing on the LXx pins if desired. Thermal Management for Ceramic Package For optimum thermal performance, generally place a pattern of vias on the layer of the PCB directly underneath the IC and connect the vias to the plane which serves as a heatsink. In this specific case, since the evaluation platform was size optimized even with 2 ICs, the ICs are mounted on each side of the PCB and offset from each other to provide some PCB Cu area for each IC to dissipate heat into. In general, to ensure good thermal contact, thermal interface material such as a Sil-Pad or thermally Submit Document Feedback 4 conductive epoxy should be used to fill the gap between the vias and the bottom of the IC of the ceramic package. Additionally, the ISL70002SEH comes in both a thermally enhanced package with a heat spreading bottom which can be directly soldered to the PCB Cu pattern and a non thermally enhanced package which is the option installed on the ISL70002EVAL2Z. Lead Strain Relief The package leads protrude from the bottom of the package and the leads need forming to provide strain relief. On the ceramic bottom package R64.A, the Sil-pad or epoxy maybe be used to fill the gap left between the PCB board and the bottom of the package when lead forming is completed. On the heatsink option of the package R64.C, the lead forming should be made so that the bottom of the heatsink and the formed leads are flush. General Heatsink Mounting Guidelines The R64.C package option has a heatsink mounted on the underside of the package. The following JESD-51x series guidelines may be used to mount the package: 1. Place a thermal land on the PCB under the heatsink. 2. The land should be approximately the same size as to 1mm larger than the 10.16x10.16mm heatsink. 3. Place an array of thermal vias below the thermal land. - Via array size: ~9x9 = 81 thermal vias. - Via diameter: ~0.3mm drill diameter with plated copper on the inside of each via. - Via pitch: ~1.2mm. - Vias should drop to and contact as much metal area as feasible to provide the best thermal path. Heatsink Electrical Potential The heatsink is connected to pin 50 within the package; thus the PCB design and potential applied to pin 50 will therefore define the heatsink potential. In this evaluation board pin 50 and the heatsink are connected to ground. Heatsink Mounting Materials In the case of electrically conductive mounting methods (conductive epoxy, solder, etc) the thermal land, vias and connected plane(s) below must be the same potential as pin 50. In the case of electrically nonconductive mounting methods (nonconductive epoxy), the heatsink and pin 50 could have different electrical potential than the thermal land, vias and connected plane(s) below. References [1] Venable Industries, Venable Technical Paper #1, “Testing Power Sources for Stability” [2] Dr. Ray Ridley, “Loop Gain Measurement Injection Technique” AN1953.0 September 23, 2014 Application Note 1953 Typical Performance Curves Efficiency data taken with (Best Case Thermal Condition) the ISL70002SEHEVAL2Z immersed in a calibrated temperature liquid bath to ensure notated ambient and package case temperatures on both IC component sides of this evaluation board. In typical lab air ambient test condition efficiency will be lower. 100 100 +25°C 95 -55°C +25°C 90 EFFICIENCY (%) EFFICIENCY (%) 95 85 80 75 +85°C 70 65 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 75 +85°C 70 +125°C 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) FIGURE 7. EFFICIENCY vs LOAD vs CASE TEMPERATURE VIN = 3.3V, VOUT = 1.0V, fSW = 1MHz 100 100 +25°C -55°C 95 90 EFFICIENCY (%) EFFICIENCY (%) 80 60 FIGURE 6. EFFICIENCY vs LOAD vs CASE TEMPERATURE VIN = 3.3V, VOUT = 1.0V, fSW = 500kHz 85 80 +85°C 75 70 90 80 75 65 65 60 60 +125°C 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) LOAD CURRENT (A) 1.8VOUT 95 EFFICIENCY (%) 80 1.5VOUT 70 100 95 85 1.2VOUT FIGURE 9. EFFICIENCY vs LOAD vs CASE TEMPERATURE VIN = 5V, VOUT = 1.0V, fSW = 1MHz 2.5VOUT 90 1.0VOUT 0.9VOUT 65 60 +85°C 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 100 75 -55°C +25°C 85 70 +125°C FIGURE 8. EFFICIENCY vs LOAD vs CASE TEMPERATURE VIN = 5V, VOUT = 1.0V, fSW = 500kHz EFFICIENCY (%) 85 65 +125°C LOAD CURRENT (A) 95 -55°C 90 1.8VOUT 85 80 75 70 1.5VOUT 1.2VOUT 65 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) FIGURE 10. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 500kHz, -55°C CASE TEMPERATURE Submit Document Feedback 5 2.5VOUT 90 60 1.0VOUT 0.9VOUT 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) FIGURE 11. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 1MHz, -55°C CASE TEMPERATURE AN1953.0 September 23, 2014 Application Note 1953 Typical Performance Curves Efficiency data taken with (Best Case Thermal Condition) the ISL70002SEHEVAL2Z immersed in a calibrated temperature liquid bath to ensure notated ambient and package case temperatures on both IC component sides of this evaluation board. In typical lab air ambient test condition efficiency will be lower. (Continued) 100 3.3VOUT 95 95 90 90 EFFICIENCY (%) EFFICIENCY (%) 100 85 80 75 1.8VOUT 1.5VOUT 2.5VOUT 1.0VOUT 1.2VOUT 70 0.9VOUT 60 1.2VOUT 1.8VOUT 1.5VOUT EFFICIENCY (%) EFFICIENCY (%) 1.0VOUT 75 70 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) 85 80 75 65 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) 100 1.8VOUT 2.5VOUT 95 95 EFFICIENCY (%) 80 1.0VOUT 70 1.2VOUT 0.9VOUT 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) 1.8VOUT 2.5VOUT 3.3VOUT 90 85 80 75 70 1.5VOUT 1.2VOUT 1.0VOUT 65 65 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) FIGURE 16. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 500kHz, +25°C CASE TEMPERATURE Submit Document Feedback 6 1.8VOUT 1.5VOUT 0.9VOUT 100 85 1.2VOUT 1.0VOUT FIGURE 15. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 1MHz, +25°C CASE TEMPERATURE 3.3VOUT 90 1.5VOUT 2.5VOUT 90 70 0.9VOUT FIGURE 14. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 500kHz, +25°C CASE TEMPERATURE EFFICIENCY (%) 0.9VOUT 95 85 60 1.2VOUT 1.0VOUT FIGURE 13. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 1MHz, -55°C CASE TEMPERATURE 2.5VOUT 90 75 1.5VOUT 2.5VOUT 100 95 60 1.8VOUT 75 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) 100 65 80 65 FIGURE 12. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 500kHz, -55°C CASE TEMPERATURE 80 85 70 65 3.3VOUT 60 0.9VOUT 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) FIGURE 17. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 1MHz, +25°C CASE TEMPERATURE AN1953.0 September 23, 2014 Application Note 1953 Typical Performance Curves Efficiency data taken with (Best Case Thermal Condition) the ISL70002SEHEVAL2Z immersed in a calibrated temperature liquid bath to ensure notated ambient and package case temperatures on both IC component sides of this evaluation board. In typical lab air ambient test condition efficiency will be lower. (Continued) 100 100 1.8VOUT 90 85 80 75 1.5VOUT 1.2VOUT 70 0.9VOUT 85 80 75 1.5VOUT 1.2VOUT 1.0VOUT 65 0.9VOUT 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) LOAD CURRENT (A) FIGURE 18. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 500kHz, +85°C CASE TEMPERATURE 100 1.8VOUT 2.5VOUT 95 85 80 1.5VOUT 70 1.2VOUT 100 3.3VOUT 90 75 FIGURE 19. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 1MHz, +85°C CASE TEMPERATURE EFFICIENCY (%) EFFICIENCY (%) 95 1.8VOUT 0.9VOUT 3.3VOUT 85 80 75 1.5VOUT 1.2VOUT 65 1.0VOUT 0.9VOUT 60 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 LOAD CURRENT (A) LOAD CURRENT (A) FIGURE 20. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 500kHz, +85°C CASE TEMPERATURE FIGURE 21. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 1MHz, +85°C CASE TEMPERATURE 100 100 2.5VOUT 95 2.5VOUT 95 1.8VOUT 90 EFFICIENCY (%) EFFICIENCY (%) 2.5VOUT 90 70 1.0VOUT 65 85 80 75 1.5VOUT 70 1.2VOUT 65 1.0VOUT 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 LOAD CURRENT (A) FIGURE 22. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 500kHz, +125°C CASE TEMPERATURE Submit Document Feedback 7 85 80 75 1.5VOUT 1.2VOUT 1.0VOUT 0.9VOUT 65 0.9VOUT 1 1.8VOUT 90 70 60 0 2.5VOUT 1.8VOUT 90 70 1.0VOUT 65 60 95 2.5VOUT EFFICIENCY (%) EFFICIENCY (%) 95 60 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 LOAD CURRENT (A) FIGURE 23. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 3.3V, fSW = 1MHz, +125°C CASE TEMPERATURE AN1953.0 September 23, 2014 Application Note 1953 Typical Performance Curves Efficiency data taken with (Best Case Thermal Condition) the ISL70002SEHEVAL2Z immersed in a calibrated temperature liquid bath to ensure notated ambient and package case temperatures on both IC component sides of this evaluation board. In typical lab air ambient test condition efficiency will be lower. (Continued) 100 100 3.3VOUT 90 85 80 75 70 1.5VOUT 1.2VOUT 65 60 1 2 3 4 5 75 1.5VOUT 1.2VOUT 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 LOAD CURRENT (A) 200 150 GAIN 20 50 0 0 -50 -20 -100 -40 1k 10k FREQUENCY (Hz) 100k -200 1M -100 -40 -60 100 -150 1k 10k FREQUENCY (Hz) -200 1M 100k FIGURE 26. GAIN AND PHASE PLOTS, 9A LOAD, VIN = 3.3V, VOUT = 1.0V, fSW = 500kHz, SCO = 0, SC1 = 0 FIGURE 27. GAIN AND PHASE PLOTS, 9A LOAD, VIN = 3.3V, VOUT = 1.0V, fSW = 500kHz, SCO = 1, SC1 = 1 1.00020 1.00020 1.00015 1.00015 1.00010 1.00010 1.00005 1.00005 OUTPUT (V) OUTPUT (V) -60 100 -150 1.00000 0.99995 0.99990 1.00000 0.99995 0.99990 0.99985 0.99985 0.99980 0.99980 0.99975 0.99975 0.99970 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 LOAD CURRENT (A) FIGURE 28. 0A - 21A VOUT LOAD CURRENT REGULATION VIN = 3.3V, VOUT = 1.0V, fSW = 500kHz Submit Document Feedback 8 100 PHASE (°) -50 PHASE PHASE (°) 0 -20 1 100 50 0 0 40 GAIN (dB) PHASE 0.9VOUT 60 150 GAIN 20 1.0VOUT FIGURE 25. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW = 1MHz, +125°C CASE TEMPERATURE 200 60 GAIN (dB) 80 60 6 7 8 9 10 11 12 13 14 15 16 17 LOAD CURRENT (A) 3.3VOUT 85 65 FIGURE 24. EFFICIENCY vs LOAD vs OUTPUT VOLTAGE VIN = 5V, fSW= 500kHz, +125°C CASE TEMPERATURE 40 2.5VOUT 90 70 1.0VOUT 0.9VOUT 0 1.8VOUT 95 EFFICIENCY (%) EFFICIENCY (%) 2.5VOUT 1.8VOUT 95 0.99970 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 LOAD CURRENT (A) FIGURE 29. VOUT LOAD CURRENT REGULATION VIN = 5V, VOUT = 1.0V, fSW = 500kHz AN1953.0 September 23, 2014 VIN C8 C9 3 L1 LX 3 3 J18 1 J39 1UF C24 C22 150UF C25 150UF C23 C21 150UF 10 R25 J40 TP11A C20 UNNAMED_1_SMCAP_I355_A FB R19 J32 C17 UNNAMED_1_SMCAP_I248_B J30 0 UNNAMED_1_JUMPER2_I61_IN1 UNNAMED_1_JUMPER2_I55_IN2 4700PF R21 R22 1K 100 UNNAMED_1_JUMPER2_I59_IN1 C9S 6800PF R9S R8S R10S R11S 4.02K 19.6K 19.6K 4.02K TP8A TP9A 1.5K R20 2 1 C8S 6800PF FSEL OPEN VIN C16 3 PORSEL SYNC TP2A J13 VOUT 1.0UH UNNAMED_1_SMCAP_I397_A TP1A 1 TP13A PVIN3 NC/HS 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 REF OCA OCSSA OCB OCSSB EN PVIN1 LX1 PGND1 PGND2 LX2 PVIN2 SC1 SC0 TP12A DNP MASTER 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 R18 ISHCOM C3 0.01UF PGOOD C14 0.1UF C36 1UF C34 C30 1UF PORSEL J36 TP10B 2 Application Note 1953 0.01UF ISL70002SEHVF PGOOD 1 2N7002 LX3 PGND3 PGND4 LX4 PVIN4 PVIN5 LX5 PGND5 PGND6 LX6 PVIN6 PVIN7 LX7 PGND7 PGND8 LX8 SC0 2 1000PF DVDD SS PGOOD ISHCOM TP5B U1 17 18 TDO 19 TDI 20 TPGM 21 GND 22 SYNC 23 PVIN10 24 LX10 25 PGND10 26 PGND9 27 LX9 28 PVIN9 29 M/S 30 FSEL 31 NC 32 UNNAMED_1_GT11MSCKE_I179_COM C12 2 S1 R15 3 10K 1 FB ISHA ISHREFA ISHB ISHREFB ISHC ISHREFC AVDD AGND DGND DVDD SS PGOOD ISHCOM ISHSL ISHEN SC1 UNNAMED_1_2N7002_I99_D Q1 J33 PVIN8 1K R16 TP4B TP6A 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 ISHA ISHREFA ISHB ISHREFB ISHC ISHREFC AVDD TP3A ENABLE 0.22UF C31 9 FB OPEN TP16A 2 D1 UNNAMED_1_ISL70002SEH_I462_64 UNNAMED_1_ISL70002SEH_I462_63 UNNAMED_1_ISL70002SEH_I462_62 UNNAMED_1_ISL70002SEH_I462_61 UNNAMED_1_ISL70002SEH_I462_60 VIN FSEL 1 UNNAMED_1_SMLED_I101_A 1K 1K R17 1 1 R13 R14 C13 1UF C10 1UF C7 1UF C1 1UF C15 150UF C11 150UF C4 C5 150UF R24 J2 2 1 SC0 J1 PORSEL 150UF SC1 VIN 2 C27 4.02K C26 19.6K 150UF 19.6K 150UF R11 4.02K 3 R10 J29 R8 J27 R9 J31 TP7A 6800PF 3 6800PF 150UF Submit Document Feedback ISL70002SEHEVAL2Z Schematic R23 5K TP15A VIN SC1 SC0 R24S TP4A DVDDS SSS PGOODS ISHCOM C2 C14S 0.01UF C36S 0.22UF 1UF C34S 1UF C30S PGOODS TP5A ISL70002SEHVF PORSEL FSEL PORSEL PGOODS 1 TP10A 2 FSEL TP12B L1S DRAWN BY: DATE: OSCAR MANSILLA RELEASED BY: 1UF C27S 150UF C26S 150UF C24S 150UF C22S C25S 150UF 150UF C21S C20S 1.0UH C23S UNNAMED_1_SMCAP_I502_A 150UF LXS 1000PF 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 10 LX3 PGND3 PGND4 LX4 PVIN4 PVIN5 LX5 PGND5 PGND6 LX6 PVIN6 PVIN7 LX7 PGND7 PGND8 LX8 R25S U2 UNNAMED_1_2N7002_I485_D 2N7002 PVIN3 NC/HS 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 REF FB ISHA ISHREFA ISHB ISHREFB ISHC ISHREFC AVDD AGND DGND DVDD SS PGOOD ISHCOM ISHSL ISHEN OCA OCSSA OCB OCSSB EN PVIN1 LX1 PGND1 PGND2 LX2 PVIN2 SC1 SC0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 3 Q1S J33S PVIN8 TP3B OPEN SLAVE ISHA ISHREFA ISHB ISHREFB ISHC ISHREFC AVDDS 17 18 TDO 19 TDI 20 TPGM 21 GND 22 SYNC 23 PVIN10 24 LX10 25 PGND10 26 PGND9 27 LX9 28 PVIN9 29 M/S 30 FSEL 31 NC 32 C31S DNP TP14A D1S 1K UNNAMED_1_ISL70002SEH_I519_64 UNNAMED_1_ISL70002SEH_I519_63 UNNAMED_1_ISL70002SEH_I519_62 UNNAMED_1_ISL70002SEH_I519_61 UNNAMED_1_ISL70002SEH_I519_60 0.22UF 1K R17S 1 R14S 1 R13S 1UF C13S 1UF 1UF C10S C7S 1UF C6S C15S 150UF 150UF C11S C4S 150UF C5S 150UF UNNAMED_1_SMLED_I483_A R1 ENGINEER: 03-27-2014 DATE: DATE: OSCAR MANSILLA TITLE: ISL70002SEH UPDATED BY: DATE: TIM KLEMANN DUAL UNIT OPERATION 05/06/2014 SCHEMATIC TESTER $CDS_IMAGE|intersil_color_sm.jpg|1194|282 MASK# FILENAME: ~/ISL70002SEH/ISL70002SEHEVAL2ZA HRDWR ID SHEET REV. 1 OF A 1 AN1953.0 September 23, 2014 Application Note 1953 Bill of Materials REFERENCE DESIGNATOR QTY PART NUMBER U1, U2 2 12A SYNCHRONOUS BUCK REGULATOR W/MOSFET ISL70002SEHVF L1, L1S 2 LOW PROFILE HIGH CURRENT INDUCTOR (RoHS COMPLIANT) IHLP-5050CE-ER-1R0-M-01 VISHAY J33, J36, J33S DESCRIPTION MANUFACTURER INTERSIL 3 Scope Probe Test Point PCB Mount 131-4353-00 TEKTRONIX Q1, Q1S 2 N-Channel EMF Effect Transistor 2N7002 FAIRCHILD R23 1 TRIMMER POTENTIOMETER (RoHS COMPLIANT) 3299W-1-502-LF BOURNS TP2, TP12, TP12S 3 Miniature Black Test Point 0.100 Pad 0.040 Thole 5001 KEYSTONE TP1, TP3-TP5, TP7-TP11, TP13-TP16, TP3S-TP5S, TP10S 17 Miniature White Test Point 0.100 Pad 0.040 Thole 5002 KEYSTONE TP6 1 Miniature Orange Test Point 0.100 Pad 0.040 Thole 5003 KEYSTONE J1, J2, J39, J40 4 SOLDER MOUNT BANANA PLUG 575-4 KEYSTONE C20, C20S 2 Ceramic Chip Cap C0805C102K2RAC KEMET C12, C14, C14S 3 Ceramic Chip Cap C0805C103K2RAC KEMET C8, C9, C8S, C9S 4 Multilayer Cap C0805C682K2RAC KEMET C36, C36S 2 Ceramic Chip Cap C1210C104K2RAC KEMET C17 1 Multilayer Cap C1812C472F2GAC KEMET C31, C31S 2 Ceramic Chip Cap C1825C224K2RAC KEMET C1, C7, C10, C13, C27, C30, C34, C6S, C7S, C10S, C13S, C27S, C30S, C34S 14 Multilayer Cap C2225C105K2RAC KEMET S1 1 SPDT On-None-On SMT Ultraminiture Toggle Switch (RoHS compliant) GT11MSCBE-T C&K C2, C3 2 Multilayer Cap H1045-OPEN GENERIC C16 1 Ceramic Chip Cap H1082-OPEN GENERIC R18 1 Metal Film Chip Resistor (Do Not Populate) H2505-DNP-DNP-1 GENERIC R1 1 Metal Film Chip Resistor (Do Not Populate) H2505-DNP-DNP-R1 GENERIC R19 1 Thick Film Chip Resistor H2511-00R00-1/16W1 GENERIC R24, R24S 2 Thick Film Chip Resistor H2511-01001-1/16W1 GENERIC J13, J18, J27, J29 4 Three Pin Jumper JUMPER-3-100 GENERIC J30-J32 3 Two Pin Jumper JUMPER2_100 GENERIC D1, D1S 2 AllnGaP Green LTST-C190KGKT LITEON R16 1 Metal Film Chip Resistor MCR03EZPFX1001 ROHM R17, R21, R17S 3 Thick Film Chip Resistor S0603CA1001BEB State of the Art R20 1 25ppm Thin Film Chip Resistor S0603CA1501BEZ State of the Art R8, R10, R8S, R10S 4 25ppm Thin Film Chip Resistor S0603CA1962BEZ State of the Art R9, R11, R9S, R11S 4 25ppm Thin Film Chip Resistor S0603CA4021BEZ State of the Art R22 1 100ppm Thick Film Chip Resistor S0603CPZ1000F10 State of the Art R15 1 100ppm Thick Film Chip Resistor S0603CPZ1002F10 State of the Art R13, R14, R13S, R14S 4 100ppm Thick Film Chip Resistor S0603CPZ1R00F10 State of the Art R25, R25S 2 100ppm Thick Film Chip Resistor S1206CPZ10R0F10 State of the Art C4, C5, C11, C15, C21-C26, C4S, C5S, C11S, C15S, C21S-C26S 20 High Capacitance Ultra-Low ESR Tantalum SMD Cap T530D157M010AHE006 KEMET Submit Document Feedback 10 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout FIGURE 30. TOP SILK SCREEN FIGURE 31. TOP LAYER COMPONENT PLACEMENT Submit Document Feedback 11 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout (Continued) FIGURE 32. TOP COMPONENT LAYER FIGURE 33. LAYER 2 Submit Document Feedback 12 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout (Continued) FIGURE 34. LAYER 3 FIGURE 35. LAYER 4 Submit Document Feedback 13 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout (Continued) FIGURE 36. LAYER 5 FIGURE 37. LAYER 6 Submit Document Feedback 14 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout (Continued) FIGURE 38. LAYER 7 FIGURE 39. BOTTOM COMPONENT LAYER 8 Submit Document Feedback 15 AN1953.0 September 23, 2014 Application Note 1953 ISL70002SEHEVAL2Z Layout (Continued) FIGURE 40. BOTTOM LAYER COMPONENT PLACEMENT FIGURE 41. BOTTOM SILK SCREEN 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 16 AN1953.0 September 23, 2014