ISL6424 Dual LNB Controller with I2C Interface for Advanced Satellite Set-Top Box Designs ® Application Note Introduction Communication Satellite Frequency Allocation Communication satellites operate within two frequency bands for TV/Broadband service broadcast signals, C Band and Ku Band. The C Band overall frequency spectrum is 4.0GHz - 8.0GHz, while the Ku Band overall frequency spectrum is 11.7GHz -18.0GHz. Within these bands each satellite will have specific uplink and downlink frequency allocation. For example the North American DBS system has categories assigned as follows, Ku Band high power downlink is 12.2GHz –12.7GHz and 17.3GHz-17.8GHz as the uplink frequency, C Band downlink frequency is 3.7GHz to 4.2GHz and 5.925GHz-6.425GHz as uplink frequency. Also, to use the frequencies that are available for satellite broadcast as efficiently as possible, and to accommodate additional number of channels within a given frequency band, the transmission signal can be formatted to be either vertical and horizontal, or circular right-hand and circular lefthand simultaneously per frequency. What is a Low Noise Block (LNB)? An LNB is a low noise block module, placed on the focus of the dish antenna (parabola) that provides the following functions: • Down conversion of the incoming signal from GHz range to 910MHz -2150MHz (for Europe) range called “first conversion signal.” This conversion allows the signal to be carried by an inexpensive coaxial cable towards the receiver. • Signal amplification with good noise factor. The LNB improves the first conversion signal level through the use of a built-in low noise amplifier. • Selects Vertical or Horizontal polarization. • Selects operating band by switching its internal oscillator from Low band to High band when it “receives” a 22kHz tone. Specifically the local oscillator (LO) frequency changes from 9.75GHz to 10.6GHz. C Band - LO frequency 9.75GHz Ku Band - LO frequency 10.6GHz • Miscellaneous functions based on 22kHz tone PPM encoding, as discussed later in the paper. AN1177.0 (right-hand or left-hand). Consequently, the satellite can broadcast both H and V or LH and RH polarized signals via one frequency. The “universal” LNB switches the polarization by looking at the voltage that it receives from the receiver. 12V – Horizontal, 18V – Vertical 13V – Circular right-hand, 20V – Circular left-hand Generally, only two (12V and 18V or 13V and 20V) will be used with one type of Antenna. Also 1V can be added from a receiver to any of above voltages to compensate for the voltage drop in the coaxial cable, i.e., it could be 13V (12V), 14V (13V), 19V (18V) or 21V (20V) instead. 22kHz Tone and DiSEqC™ (Digital Satellite Equipment Control) Encoding In addition to selecting the polarization, the LNB needs to select the operating band. This is done with the use of a 22kHz tone frequency. A 22kHz pulse-position modulated signal of about 0.6V amplitude is superimposed on the LNB’s DC power rail. Its coding scheme allows the remote electronics to perform more complex functions like varying the down conversion frequency to select one of multiple LNB’s for dual-dish systems or physically rotating the antenna assembly. Traditionally, when other encoding functions do not require using 22kHz tone, simple presence or absence of this tone selects the operating band by changing the local oscillator frequency of the LNB. The complex encoding of 22kHz burst is done with a more sophisticated communication bus protocol named DiSEqC standard (Digital Satellite Equipment Control). The open DiSEqC standard developed by the European Telecommunication Satellite Organization is a well accepted worldwide standard for communication between satellite receivers and satellite peripheral equipment. The 22kHz oscillator has to be a tone generator with specific rise and fall time. The wave shape will be a quasi-square wave. (Sine with flat-top). The required frequency tolerance is ±2kHz over line and temperature variations. Burst coding of this signal is accomplished by input from the microcontroller at the DSQIN pin of the IC as detailed in the datasheet. 22kHz WAVE SHAPE AND DETAILS (See Figures 1 and 2) Polarization Selection Polarization is a way to give a transmission signal specific direction. It increases the beam concentration. The signal transmitted by satellite can be polarized in one of four different ways: Linear (horizontal or vertical) or Circular 1 March 21, 2005 Carrier frequency: 22kHz ±2kHz over line and temperature Carrier amplitude: 650mVpp ±250mV Modulation mark period: 500µs ±100µs Modulation space period: 1ms ±200µs CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures. 1-888-INTERSIL or 1-888-352-6832 | Intersil (and design) is a registered trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005. All Rights Reserved All other trademarks mentioned are the property of their respective owners. Application Note 1177 Quick Start Evaluation Methods of Modulation ‘0’ DATA BIT 1.0ms ‘1’ DATA BIT 0.5ms 0.5ms 1.0ms FIGURE 1. DiSEqC™ MODULATION SCHEME ‘0’ TONE BURST (SATELLITE A) Out Of The Box The ISL6424 evaluation board is shipped in a “ready-to-test” state. The board requires an input voltage ranging from 8V to 14V and a 3.3V/5V supply. The use of an electronic load enables evaluation over a wide range of operating conditions. The evaluation kit also includes 5 samples of ISL6424EEB and ISL6424ER, a PC to I2C bus interface board (USB-I2CIO), PC to I2C bus software, a USB cable, and a connector cable to connect the USB-I2CIO board and the ISL6424EVAL board. TABLE 1. ISL6424 EVALUATION BOARDS ‘1’ DATA BURST (SATELLITE B) 12.5ms FIGURE 2. TIMING DIAGRAM FOR TONE BURST CONTROL SIGNAL BOARD NAME IC ISL6424EVAL1C ISL6424EEB 28-Ld SOIC ISL6424EVAL2C ISL6424ER 32-Ld QFN Required Test Equipment To fully test the ISL6424 chip functionality, the follow equipment is needed: ISL6424 - Provides a Complete Power Solution for Dual LNB Control • 4 channel oscilloscope with probes The ISL6424 is a highly integrated solution for supplying power and control signals from advanced satellite set-top box (STB) modules to the low noise blocks (LNBs) of two antenna ports. This dual output device is comprised of two independent current-mode boost PWMs and two low-noise linear regulators along with the circuitry required for I2C device interfacing and for providing DiSEqC standard control signals to the LNB. • 2 bench power supplies Regulator output voltages are available at two output terminals (VO1, VO2) to support simultaneous operation of two antenna ports in advanced satellite STBs. The regulator outputs for each PWM are set to 13V or 18V by independent voltage select commands (VSEL1, VSEL2) through the I2C bus. Additionally, to compensate for the voltage drop in the coaxial cable, the selected voltage may be increased by 1V with the line length compensation (LLC) feature. Separate enable commands sent on the I2C bus provide independent standby mode control for each PWM and linear combination, disabling the output to conserve power. Both independent tracking current-mode boost converters provide the linear regulators with input voltages that are set to the output voltages, plus typically 1.2V dropout to insure minimum power dissipation across each linear regulator. This maintains constant voltage drops across each linear pass element while permitting adequate voltage range for tone injection. Please refer to the ISL6424 datasheet, FN9175, for more information. 2 PACKAGE • 2 electronic loads • Precision digital multi-meters • I2C bus read/write capability Power and Load Connections Refer to the ISL6424EVAL1 and 2 schematics, the reference designators will differ. The ISL6424EVAL1 evaluation board has four sets of terminal posts and three jumpers that are used to supply the input voltages and to monitor and load the outputs. Jumper and Switch Settings - JP1, JP2, and JP3 will be shorted with shunt jumpers for quick start evaluation. JP1 and JP2 can be removed to monitor the input current for each boost regulator or the input bias current of the IC. JP3 sets the chip address to 0. The control pins for DSQIN1, DSQIN2, SEL18V1, and SEL18V2 are available at respective terminal posts. These are by default in the low condition. They will have to be pulled high to activate the respective function. Input Voltage - Adjust two power supplies to provide the 5V/3.3V and 12V input voltages of the evaluation board. With the power supplies turned off, connect the positive lead of the 12V supply to the VIN post (P1) and the ground lead to the GND post (P2). The second supply set for either 5V or 3.3V provides the pull-up voltage for the I2C bus clock and data line. Connect the positive lead of the second supply to the +5V/+3.3V post (P5) and the ground lead to the GND post (P10-EVAL2). AN1177.0 March 21, 2005 Application Note 1177 Output Voltage Loading and Monitoring - To exercise and monitor VOUT1, connect the positive lead of one of the electronic loads and the positive lead of a digital multimeter to the VOUT1 post (P3) and the ground lead to the GND post (P4). To exercise and monitor VOUT2, connect the positive lead of one of the electronic loads and the positive lead of a digital multimeter to the VOUT2 post (P8) and the ground leads of both to the GND post (P10). I2C Bus Communication Setup To control and exercise the ISL6424 requires communication through the I2C bus clock (SCL) and data (SDA) pins. Refer to the ISL6424 datasheet for more information about the I2C bus specification. You can use the existing I2C hardware/software, a word generator, or the PC to I2C hardware/software included in the ISL6424 evaluation kit to produce the necessary I2C waveforms. DMM (3) - 4. Windows should detect the new USB device and the ‘Found New Hardware Wizard’ should begin. This will help you install the drivers. Follow the directions on the screen until it asks you where to search for the drivers. At this point, you should select the ‘choose location’ option and browse to the C:\’some directory’ created in step one and select the drivers folder. + - USB USB CABLE USB I2C INTERFACE BOARD - + - + POWER SUPPLY (2) 1. The evaluation kit comes with a CD containing the software and drivers to control the I2C bus. Copy the contents of the CD to some directory, e.g., C:\’some directory’. 3. After the USB-I2CIO board is powered up, connect the USB cable to the USB port of a PC. + COMPUTER USB-I2CIO Board Driver Installation - To use a PC to control the I2C bus to communicate with the ISL6424 you will have to install the drivers of the USB-I2CIO board included in the kit. You will need a Windows 98/XP/2000 machine with a standard USB port. 2. Applying power to the USB-I2CIO board: The USB-I2CIO board has the option of being powered with 3.3V through the USB bus of the PC or externally with 5V connected to the +5 test point and GND test point. The I2C bus can operate at 3.3V or 5V logic. If you use external 5V then place a shunt jumper shorting pins 2 and 3 of JP3. If you are using an external 5V to power the USB-I2CIO board place a shunt jumper shorting pins 1 and 2 of JP3. POWER SUPPLY (1) O-SCOPE (1) - + - ELECTRONIC LOAD & DMM (1) + - + O-SCOPE (2) ELECTRONIC LOAD & DMM (2) FIGURE 3. ISL6424EVAL1 TEST SETUP DMM (3) - POWER SUPPLY (1) + + - COMPUTER USB USB CABLE USB I2C INTERFACE BOARD 5. Follow the remaining directions and the driver should be installed and the USB-I2CIO detected by your PC. 6. If this is successful, another ‘Found New Hardware Wizard’ window will appear. Repeat steps 4 and 5. At this point, the USB-I2CIO board should be ready to use. 7. To connect the USB-I2CIO board to the ISL6424 evaluation board, use the 5-pin to 4-pin connector cable. Connect the 5-pin connector to J4 on the USB-I2CIO board and the 4-pin connector to J3 on the ISL6424 evaluation board. Figure 3 and 4 show the test setup configuration to evaluate the ISL6424 evaluation boards. + - POWER SUPPLY (2) + - O-SCOPE (1) + - ELECTRONIC LOAD & DMM (1) - + ELECTRONIC LOAD & DMM (2) - + O-SCOPE (2) FIGURE 4. ISL6424EVAL2 TEST SETUP 3 AN1177.0 March 21, 2005 Application Note 1177 8. Turn on the power supplies to power up the ISL6424 evaluation board. 9. Run the ISL6424i2crevb.exe program copied to C:\’some directory’. Figure 5 shows the PC to I2C software application window. Click the ‘Open Device’ button. 10. If you receive a ‘No USB Device Detected’ error: • Make sure the drivers were installed correctly. If Windows did not detect your USB device, try running the Add/Remove Hardware Wizard in the control panel. • Make sure the USB board is powered up (internally or externally, not both). 11. If you receive the ‘Incorrect Return Value’ error: • The ISL6424 evaluation board may not be powered up. Check the power connections. system register bits. They are read and updated continuously. The OLF1/2 and OTF flag in system register 1 and 2 are read only bits and they provide diagnostic status of the ISL6424. The switch, SW1, allows you to change the I2C address of the ISL6424 by toggling the ADDR pin high or low. With the switch in its default position the ADDR pin is low. The application software will not be able to communicate with the ISL6424 if the ADDR pin is high. Performance Characterization Startup The ISL6424 features internal soft-start to reduce external number of components. Figure 6 shows typical soft-start waveform. Typical soft-start time is 4.6ms. • Make sure SCL and SDA are connected correctly. The 5-pin connector to the USB-I2CIO board only fits one way. Try reversing the 4-pin connector at J3 of the ISL6424 evaluation board. VOUT1 5V/DIV VOUT2 5V/DIV 100µs/DIV FIGURE 6. SOFT-START Shutdown Both LNB outputs of ISL6424 can be independently shutdown using ENx bits via I2C. Figure 7 shows typical shutdown waveforms. VO1 5V/DIV FIGURE 5. PC TO I2C APPLICATION WINDOW VO2 5V/DIV Using the PC to I2C Application After opening the application window and clicking on the ‘Open Device’ button, the program will detect the USB-I2CIO board and initialize the I2C system registers of the ISL6424. To evaluate the ISL6424 functionality, toggle the system register bits as needed and then click on the ‘Write I2C’ button to write to the system registers. The lower portion of the application window shows the current values of the 4 100µs/DIV FIGURE 7. SHUTDOWN USING I2C ENABLE AN1177.0 March 21, 2005 Application Note 1177 Boost PWM Efficiency Overcurrent Hiccup Mode The Boost PWM architecture allows close to 90% efficiency at full load as shown in Figure 8. Figure 10 shows a typical overcurrent trip. 100 95 PWM2 EFFICIENCY (%) 90 IO1 200mA/DIV PWM1 85 80 75 VO1 10V/DIV 70 65 50µs/DIV 60 50 150 250 350 450 550 650 750 FIGURE 10. OVERCURRENT TRIP IOUT (mA) FIGURE 8. BOOST PWM1 AND PWM2 EFFICIENCY vs LOAD DiSEqC Implementation The ISL6424 has a built-in 22kHz tone generator that can be controlled either by the I2C interface or by a dedicated pin (DSQIN) that allows immediate DiSEqC data encoding for the DiSEqC compliance. When the I2C tone enable bit (ENT) is set to HIGH, a continuous 22kHz tone is generated regardless the status of the DSQIN pin. The ENT pin must be LOW when DSQINx pins are being used for DiSEqC encoding. Figure 9 shows the 22kHz tone waveform with 350mA load. When the DCL (dynamic current limiting) bit is set LOW, the overcurrent protection circuit works dynamically; as soon as an overload is detected, the output is shutdown for a time tOFF, typically 900ms. The output is resumed for a time tON = 20ms. At the end of tON, if the overload condition is still detected, the protection circuit will cycle again through tOFF and tON. Figure 12 shows the typical waveforms for the overcurrent hiccup mode. 200mV/DIV IO1 200mA/DIV VO1 10V/DIV 22kHz TONE 500ms/DIV FIGURE 11. OVERCURRENT HICCUP MODE tRISE = 8µs tFALL = 7.4µs 20µs/DIV FIGURE 9. 22kHz TONE OPERATION 5 AN1177.0 March 21, 2005 Application Note 1177 Output Ripple Figure 12 shows the typical output ripple waveforms. VO1 is set to 19V and 750mA load. VO2 is set to 13V and 350mA load. D1 STPS2L40U ISL6424 (LLC = HIGH) LNB CD CLOAD X DEVICE VO1 20mV/DIV VO2 20mV/DIV FIGURE 14. DC BACK-BIAS PROTECTION CIRCUIT FOR ZERO LOAD CONDITION 200µs/DIV FIGURE 12. OUTPUT RIPPLE External Back-Bias Protection Some applications may need to be able to protect the ISL6424 from an inadvertent back-bias voltage condition. For the case where a 24V supply is connected to the output of the ISL6424, a series connected diode as shown in Figure 13 will protect the IC. The LLC bit can be set high through the I2C bus to increase the output voltage by 1V to compensate for the diode voltage drop. D1 STPS2L40U ISL6424 (LLC = HIGH) During the tone fall time, the capacitors are essentially in series so the charge will try to equally distribute between Cd and Cload. Cload will discharge allowing current to flow to Cd to match the falling voltage at the anode of the diode. You will have to choose a capacitor, Cd, that is large enough to absorb the Cload discharging current and to minimize the voltage drop created during the minimum tone fall time specification, 5µs. A good choice would be to use a capacitor for Cd that is 4 times the value of Cload. Figure 15 shows the tone mode operation at the cathode of the protection diode in a zero load condition and the charging current between Cd and Cload. Excessive current transients may occur from a fast dV/dt created if a 24V supply were connected to the output of the ISL6424, therefore, to use the circuit in Figure 14, the 24V supply would have to be limited to 1A maximum current considering the dV/dt voltage transient, to fully protect the IC. LNB VD CLOAD X DEVICE ICLOAD 20mA/DIV FIGURE 13. DC BACK-BIAS PROTECTION CIRCUIT The DiSEqC standard recommends a maximum bus load of 0.25µF. For the circuit in Figure 13 to provide proper 22kHz tone operation, the bus would have to have a minimum loading of 12mA. If tone operation is required at zero load conditions, a resistor can be placed from the cathode of the protection diode to ground, scaled to provide the minimum 12mA. To avoid the added dissipation of this method, a capacitor can be placed in parallel with the back-bias protection diode as shown in Figure 14. This capacitor should be scaled with the capacitive load present on the DiSEqC bus line. For a load of 0.25µF, use a 10µF capacitor. Consider the maximum load of 0.25µF and the highest output voltage of 19V and a 0.5V drop across the Schottky diode. After the tone rise time, Qd(rise)~0, Qload(rise) = 19V*0.25µF = 4750nC. 6 VO1 200mV/DIV FIGURE 15. ZERO LOAD 22kHz TONE AT CATHODE OF DIODE AND DRIVING CURRENT CHARGING AND DISCHARGING CLOAD AN1177.0 March 21, 2005 Application Note 1177 Component Selection Guidelines Inductor The ISL6424EVAL application schematics show the configuration for a dual LNB power supply. The ISL6424 operates with a 33µH standard inductor over the entire range of supply voltages and load currents. Choose an inductor that can handle at least the peak switch current without saturating, and ensure that the inductor has a low DCR (series resistance) to maximize efficiency. The inductor saturation current must be greater then the switch peak current, TCAP Capacitor A capacitor connected to the TCAP pin sets the transition time from 13V to 18V. A minimum 1µF capacitor is required for smooth transition with reduced peak currents. Figure 16 shows the transition time versus capacitor value. V SW ( max ) ⋅ I OUT V IN ( min ) V IN ( min ) I PEAK = --------------------------------------------- - + ----------------------- 1 – --------------------------2L ⋅ f SW V SW ( max ) N ⋅ V IN ( min ) (EQ. 1) 3.8 where, RISE/FALL TIME (ms) 3.3 L = Inductance 33µH 2.8 fSW = PWM switching frequency, 220kHz Typical 2.3 N = Efficiency, 92% at maximum load 1.8 TABLE 2. RECOMMENDED INDUCTORS 1.3 PART NUMBER ISAT (A) DCR (mΩ) PACKAGE Coilcraft MSS1260-333MX 2.2 75 SMD Falco SD1016 2.8 66 SMD VENDOR 0.8 0.3 0.15 0.65 1.15 TCAP (µF) 1.65 2.15 FIGURE 16. TCAP CAPACITOR VALUE vs OUTPUT TRANSITION TIME The programmed output voltage rise and fall times can be set by an external capacitor. The output rise and fall times will be approximately 3400 times the TCAP value. For the recommended range of 0.47µF to 2.2µF, the rise and fall time would be 1.6ms to 7.6ms. Use of a 0.47µF capacitor insures the PWM will stay below its overcurrent threshold when charging a 120µF VSW filter cap during the worst case 13V to 19V transition. This feature only affects the turn-on and programmed voltage rise and fall times. Figure 17 shows the 13V to 18V transition with TCAP=1µF. The most important parameter for the output capacitors is effective series resistance (ESR). The output ripple is directly proportional to output capacitor ESR value. A 68µF or less aluminum output filter capacitor with ESR lower than 80mΩ in parallel with a 470nF ceramic capacitor is a good choice in most application conditions. A ceramic capacitor is necessary to reduce the high frequency switching noise. A high output capacitance and low ESR will strongly reduce the output ripple voltage, output switching noise and improve efficiency. Use the lowest possible ESR capacitor for best performance. The maximum value output capacitor is restricted by transition time specifications between 13V to 18V. With a high output capacitor the boost circuit will need higher peak current from input supply to make transition from 13V to 18V in an given transition time as set by TCAP value. The Figure 16 shows the TCAP capacitor value versus transition time. Use high TCAP capacitor value for high output capacitors to allow sufficient time to charge the output capacitors in maximum load conditions. VO1 2V/DIV VO2 2V/DIV Output Capacitors 5ms/DIV The capacitor’s voltage rating should be at least 35V, but higher voltage electrolytic capacitors generally have lower ESR numbers, and for this reason, to improve efficiency and output ripple, select a capacitor with higher voltage ratings. FIGURE 17. 13V TO 18V TRANSITION 7 AN1177.0 March 21, 2005 Application Note 1177 regulator leads to a total dissipated power that is about 1.2V*750mA*2 = 1.8W. At 350mA maximum current, this power will be 1.2V*350mA*2 = 0.84W. The heat needs to be removed with a heatsink to keep the junction temperature below the over-temperature threshold. TABLE 3. VENDOR SERIES PACKAGE Sanyo OS-CON Electrolytic SMD/Through hole Panasonic EEUFC Electrolytic TH Static Current Limit The current sense resistor Rsc serves to set the peak current through the FET when in the static current limit mode. This resistor value is calculated based on peak switch current per Equation 2, V SENSE R SC < ----------------------I PEAK (EQ. 2) Where Vsense is 450mV typ. (See datasheet specification table) and Ipeak is calculated from Equation 1. Make sure the Rsc value is always lower than the Vsense/Ipeak ratio. In the typical application conditions (VCC = 12V, IPEAK (max) = 4500mA) a 100mΩ Rsc value is a good choice. If VIN < 10.5V the inductor peak current can be close to 2.5A. In the worst case with VIN = 8V, and IOUT = 500mA, low cost axial through-hole resistors could also be used, however, these are usually bigger and need a larger area on the PCB. See Table 4 for some suggested SMD resistor part numbers. TABLE 4. VENDOR SERIES KOA SR73 3A SEI Electronics RMC1 Panasonic ERJ L1W Layout Guidelines Just like all switching power supplies, a proper PC board layout is very important for a dual channel ISL6424 based power supply implementation. Protect sensitive analog grounds by using a star ground configuration. Also, minimize lead lengths to reduce stray capacitance, trace resistance, and radiated noise. Minimize ground noise by connecting PGND1/2, the input bypass capacitor ground lead, and the output filter capacitor ground lead to a single point. Place bypass capacitors as close as possible to BYP pin and PGND1/2 and the DC/DC output capacitors as close as possible to VSW1/2. The simplest solution is to use a large, continuous copper area of the ground layer to dissipate the heat. This area can be the inner ground of multi-layered pcbs, or in a dual layer pcb, or an unbroken ground area on the opposite side of the board where the IC is placed. In both cases, the thermal path between the IC ground pins and the dissipating copper area must exhibit a low thermal resistance. The EPAD SOIC package of the ISL6424 has θJA = 27°C/W and θJC = 2°C/W. The QFN package has θJA = 32°C/W and θJC = 4°C/W. Due to the presence of exposed pad connected to ground below the IC body on both the EPAD SOIC and the QFN packages, the θJC is much lower. As a result, a much smaller copper area is required to dissipate heat than standard SOIC packages. Conclusion The ISL6424 dual output voltage regulator makes an ideal choice for advanced satellite set-top box and personal video recorder applications. The ISL6424EVAL1 and ISL6424EVAL2 are complete reference designs for providing power and control functions to the LNB in advanced satellite set-top box applications. References Intersil documents are available on the web at http://www.intersil.com. [1] ISL6424 Data Sheet, Intersil Corporation, File No. FN9175 [2] DiSEqC Bus Functional Specification, EUTELSAT http://www.eutelsat.com/docs/diseqc [3] More information on the USB-I2CIO PC to I2C interface board available at http://www.DeVaSys.com Place TCAP1/2 capacitors very close to the IC pins and have shortest possible ground return path. Thermal Design During normal operation, the ISL6424 dissipates some power. The power dissipation of the output linear regulator dominates the total power dissipated in the ISL6424. At the maximum rated output current, the voltage drop on the linear 8 AN1177.0 March 21, 2005 ISL6424 EVAL1 Rev B Schematic 9 Application Note 1177 AN1177.0 March 21, 2005 Application Note 1177 Bill of Materials ISL6424EVAL1 Rev. B ITEM REFERENCE QTY PART NUMBER PART TYPE DESCRIPTION PACKAGE VENDOR 1 U1 1 ISL6424EEB IC, Linear Current mode PWM Controller 28 SOIC Intersil 2 Q1, Q2 2 FDS6612A MOSFET Single N-channel, 30V, 0.022Ω, 8.4A SOIC8 Fairchild 3 D1, D2, D3, D4 4 STPS2L40U Diode, Schottky, Low Drop Power Schottky, 30V, 2A DO-214AA STMicroelectronics 4 D5, D6 2 S1A/B Diode, Rectifying Rectifying, 50V SMB Diodes Inc. 5 D7, D8 (DNP) 0 BZT52C5V6 Diode, Zener Zener, 5.6V, 500mW SOD123 Diodes Inc. 6 L1, L2 2 MSS-1260-333MX Inductor 33µH, 20%, 2.2A MSS1260 CoilCraft 7 L3, L4 2 1008PS-472K Inductor 4.7µH, 10%, 1.0A SM CoilCraft CAPACITORS 8 C1, C4, C15, C18 4 25SP56M Capacitor, Aluminum 56µF, 20%, 25V CASE-CC Sanyo 9 C2, C5, C6, C8, C16, C19, C20, C22 8 C3225X7R1E106M Capacitor, Ceramic, X7R 10µF, 20%, 25V SM_1210 TDK/Generic 10 C3, C17 2 DNP SM_0603 TDK/Generic 11 C7, C13, C14, C21 4 C2012X7R1E105K Capacitor, Ceramic, X7R 1.0µF, 10%, 25V SM_0805 TDK/Generic 12 C9, C23 2 C1608X7R1H101K Capacitor, Ceramic, X7R 100pF, 10%, 50V SM_0603 TDK/Generic 13 C10, C25 2 C1608COG1H330K Capacitor, Ceramic, COG SM_0603 TDK/Generic 14 C11, C24 2 C1608X7R1H152K Capacitor, Ceramic, X7R 1500pF, 10%, 50V SM_0603 TDK/Generic 15 C12, C28, C31, C32, C33 5 C1608X7R1H104K Capacitor, Ceramic, X7R 0.1µF, 20%, 50V SM_0603 TDK/Generic 16 C26 1 C1608X7R1H102K Capacitor, Ceramic, X7R 1000pF, 10%, 50V SM_0603 TDK/Generic 17 C27 1 C1608X7R1H473K Capacitor, Ceramic, X7R 0.047µF, 10%, 50V SM_0603 TDK/Generic 18 C29, C30 2 C2012X7R1E224K Capacitor, Ceramic, X7R 0.22µF, 10%, 25V SM_0603 TDK/Generic DNP Resistor, Film SM_0603 Panasonic/Generic 33pF, 10%, 50V RESISTORS 19 R1, R6 (DNP) 0 20 R2, R4 2 Resistor, Power metal strip 0.1Ω, 1%, 1W SM_2512 Panasonic/Generic 21 R3, R5 2 Resistor, Film 68.1kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 22 R7, R8 2 Resistor, Film 1kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 23 R9, R10 2 Resistor, Film 470Ω, 1%, 0.1W SM_0603 Panasonic/Generic 24 R11, R12 2 Resistor, Film 10kΩ, 5%, 0.1W SM_0603 Panasonic/Generic 25 R13, R14, R16, R17 (DNP) 4 SM_0603 Panasonic/Generic 26 R15, R20, R21 3 Resistor, Film 100kΩ, 5%, 0.1W SM_0603 Panasonic/Generic 27 R18, R19 2 Resistor, Film 18.2Ω, 1%, 0.1W SM_0603 Panasonic/Generic DNP 10 Resistor, Film AN1177.0 March 21, 2005 Application Note 1177 Bill of Materials ISL6424EVAL1 Rev. B ITEM REFERENCE QTY PART NUMBER (Continued) PART TYPE DESCRIPTION PACKAGE VENDOR OTHERS 28 J1 1 22-03-2041 Connector Header Strip, 1X4 29 JP1, JP2, JP3 3 68000-236-1X2 Header 1X2 Break Strip GOLD 30 JP1, JP2, JP3 3 S9001-ND Jumper 2 pin jumper Digikey 31 SP1, SP2 2 131-4353-00 Terminal, Scope Probe Terminal, Scope Probe Tektronix 32 P1 - P12 12 160-2043-02-01-00 Turrett Post Terminal post, through PTH hole Cambion 33 4 1x4 @ .1" Molex Bumpers ISL6424EVAL1 Rev B Layout FIGURE 18. TOP SILKSCREEN 11 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL1 Rev B Layout (Continued) FIGURE 19. LAYER 1 FIGURE 20. LAYER 2 12 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL1 Rev B Layout (Continued) FIGURE 21. LAYER 3 FIGURE 22. LAYER 4 13 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL1 Rev B Layout (Continued) FIGURE 23. BOTTOM SILKSCREEN 14 AN1177.0 March 21, 2005 ISL6424 EVAL2 Schematic Diagram 15 Application Note 1177 AN1177.0 March 21, 2005 Application Note 1177 Bill of Materials ISL6424EVAL2 Rev. A ITEM REFERENCE QTY PART NUMBER 1 U1 1 ISL6424ER 2 Q1, Q2 2 3 D1, D2, D3, D4 4 PART TYPE DESCRIPTION PACKAGE VENDOR IC, Linear Current mode PWM Controller 32LD QFN (5x5) Intersil FDS6612A MOSFET Single N-channel, 30V, 0.022Ω, 8.4A SOIC8 Fairchild 4 STPS2L40U Diode, Schottky, Low Drop Power Schottky, 30V, 2A DO-214AA STMicroelectronics D5, D6 2 S1A/B Diode, Rectifying Rectifying, 50V SMB Diodes Inc. 5 D7, D8 (DNP) 0 BZT52C5V6 Diode, Zener Zener, 5.6V, 500mW SOD123 Diodes Inc. 6 L1, L2 2 MSS-1260-333MX Inductor 33µH, 20%, 2.2A MSS1260 CoilCraft 7 L3, L4 2 1008PS-472K Inductor 4.7µH, 10%, 1.0A SM CoilCraft CAPACITORS 8 C1, C4, C15, C18 4 25SP56M Capacitor, Aluminum 56µF, 20%, 25V CASE-CC Sanyo 9 C2, C5, C6, C8, C16, C19, C20, C22 8 C3225X7R1E106M Capacitor, Ceramic, X7R 10µF, 20%, 25V SM_1210 TDK/Generic 10 C3, C17 2 DNP SM_0603 TDK/Generic 11 C7, C13, C14, C21 4 C2012X7R1E105K Capacitor, Ceramic, X7R 1.0µF, 10%, 25V SM_0805 TDK/Generic 12 C9, C23 2 C1608X7R1H101K Capacitor, Ceramic, X7R 100pF, 10%, 50V SM_0603 TDK/Generic 13 C10, C25 2 C1608COG1H330K Capacitor, Ceramic, COG 33pF, 10%, 50V SM_0603 TDK/Generic 14 C11, C24 2 C1608X7R1H152K Capacitor, Ceramic, X7R 1500pF, 10%, 50V SM_0603 TDK/Generic 15 C12, C28, C31 3 C1608X7R1H104K Capacitor, Ceramic, X7R 0.1µF, 10%, 50V SM_0603 TDK/Generic 16 C26 1 C1608X7R1H102K Capacitor, Ceramic, X7R 1000pF, 10%, 50V SM_0603 TDK/Generic 17 C27 1 C1608X7R1H473K Capacitor, Ceramic, X7R 0.047µF, 10%, 50V SM_0603 TDK/Generic 18 C29, C30 2 C2012X7R1E224K Capacitor, Ceramic, X7R 0.22µF, 10%, 25V SM_0603 TDK/Generic 19 C32, C33 2 C1608X7R1H103K Capacitor, Ceramic, X7R 0.01µF, 10%, 50V SM_0603 TDK/Generic DNP Resistor, Film SM_0603 Panasonic/Generic RESISTORS 20 R1, R6 (DNP) 0 21 R2, R4 2 Resistor, Power metal strip 0.1Ω, 1%, 1W SM_2512 Panasonic/Generic 22 R3, R5 2 Resistor, Film 68.1kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 23 R7, R8 2 Resistor, Film 1kΩ, 1%, 0.1W SM_0603 Panasonic/Generic 24 R9, R10 2 Resistor, Film 470Ω, 1%, 0.1W SM_0603 Panasonic/Generic 25 R11, R12 2 Resistor, Film 10kΩ, 5%, 0.1W SM_0603 Panasonic/Generic 26 R13, R14, R16, R17 (DNP) 4 SM_0603 Panasonic/Generic 27 R15, R20, R21 3 Resistor, Film 100kΩ, 5%, 0.1W SM_0603 Panasonic/Generic 28 R18, R19 2 Resistor, Film 18.2Ω, 1%, 0.1W SM_0603 Panasonic/Generic 29 J1 1 22-03-2041 Connector Header Strip, 1X4 1x4 @ .1" Molex 30 JP1, JP2, JP3 3 68000-236-1X2 Header 1X2 Break Strip GOLD DNP Resistor, Film OTHERS 16 AN1177.0 March 21, 2005 Application Note 1177 Bill of Materials ISL6424EVAL2 Rev. A ITEM REFERENCE QTY 31 JP1, JP2, JP3 3 S9001-ND Jumper 2 pin jumper Digikey 32 SP1, SP2 2 131-4353-00 Terminal, Scope Probe Terminal, Scope Probe Tektronix 33 P1 - P12 12 160-2043-02-01-00 Turrett Post Terminal post, through hole 34 PART NUMBER (Continued) 4 PART TYPE DESCRIPTION PACKAGE PTH VENDOR Cambion Bumpers ISL6424EVAL2 Layout FIGURE 24. TOP SILKSCREEN 17 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL2 Layout (Continued) FIGURE 25. TOP LAYER COMPONENT SIDE FIGURE 26. LAYER 2 18 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL2 Layout (Continued) FIGURE 27. LAYER 3 FIGURE 28. BOTTOM LAYER SOLDER SIDE 19 AN1177.0 March 21, 2005 Application Note 1177 ISL6424EVAL2 Layout (Continued) FIGURE 29. BOTTOM SILKSCREEN All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality Intersil products are sold by description only. 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 data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 20 AN1177.0 March 21, 2005