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FDMF6704V - XSTM DrMOS The Xtra Small, High Performance, High Frequency DrMOS Module with LDO Benefits General Description The XSTM DrMOS family is Fairchild's next-generation fullyoptimized, ultra-compact, integrated MOSFET plus driver power stage solutions for high current, high frequency synchronous buck DC-DC applications. The FDMF6704V XSTM DrMOS integrates a driver IC, two power MOSFETs and a bootstrap Schottky diode along with an integrated 5 V gate drive LDO regulator into a thermally enhanced, ultra compact 6 mm x 6 mm MLP package. With an integrated approach, the complete switching power stage is optimized with regards to driver and MOSFET dynamic performance, system inductance and RDS(ON). This greatly reduces the package parasitics and layout challenges associated with conventional discrete solutions. DrMOS uses Fairchild's high performance XSTM PowerTrenchTM 5 MOSFET technology, which dramatically reduces ringing in synchronous buck converter applications. PowerTrenchTM 5 can eliminate the need for a snubber circuit in buck converter applications. The driver IC incorporates advanced features such as SMOD for improved light load efficiency and a Tri-State PWM input for compatibility with a wide range of PWM controllers. A 5 V gate drive and an improved PCB interface, optimized for a maximum low side FET exposed pad area, ensure higher performance. This product is compatible with the new Intel 6 mm x 6 mm DrMOS specification. Single 12 V power supply operation. Ultra compact size - 6 mm x 6 mm MLP, 44 % space saving compared to conventional MLP 8 mm x 8 mm DrMOS packages. Ultra compact thermally enhanced 6 mm x 6 mm MLP package 84 % smaller than conventional discrete solutions. Fully optimized system efficiency. Clean voltage waveforms with reduced ringing. High frequency operation. Compatible with a wide variety of PWM controllers in the market. Single input voltage operation. Features Internal 12 V to 5 V regulator. Synchronous driver plus FET multichip module. High current handling of 35 A. Over 93 % peak efficiency. Tri-State PWM input. Fairchild's PowerTrench(R) 5 technology MOSFETs for clean voltage waveforms and reduced ringing. Optimized for high switching frequencies of up to 1 MHz. Skip mode SMOD [low side gate turn off] input. Fairchild SyncFETTM [integrated Schottky diode] technology in the low side MOSFET. Integrated bootstrap Schottky diode. Adaptive gate drive timing for shoot-through protection. Driver output disable function [DISB# pin]. Undervoltage lockout (UVLO). Fairchild Green Packaging and RoHS compliant. Low profile SMD package. Applications Compact blade servers V-core, non V-core and VTT DC-DC converters. Desktop computers V-core, non V-core and VTT DC-DC converters. Workstations V-core, non V-core and VTT DC-DC converters. Gaming Motherboards V-core, non V-core and VTT DC-DC converters. Gaming consoles. High-current DC-DC Point of Load (POL) converters. Networking and telecom microprocessor voltage regulators. Power Train Application Circuit VDRV VIN CVDRV CVCIN tm CVIN VDRV VCIN DISB# PWM Input OFF ON DISB# RBOOT BOOT PWM SMOD# CGND Ordering Information VIN CBOOT LOUT PHASE VSWH OUTPUT COUT PGND Figure 1. Power Train Application Circuit Order Number Marking Temperature Range Device Package Packing Method Quantity FDMF6704V FDMF6704V_1 -55 C to 150 C 40 Pin, 3 DAP, MLP 6x6 mm Tape and Reel 3000 (c)2008 Fairchild Semiconductor Corporation FDMF6704V Rev.C 1 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator August 2009 VCIN VDRV BOOT VIN GH 5V Reg Q1 DISB# Overlap VSWH Control PWM VCIN SMOD# Q2 PGND GL CGND Figure 2. Functional Block Diagram 18 43 32 19 20 21 22 23 24 25 26 27 28 1 2 3 4 5 6 7 15 36 16 35 VSWH 17 18 34 33 43 19 32 20 31 PGND PGND PGND PGND PGND PGND PGND PGND VSWH VSWH VSWH VSWH PGND PGND PGND PGND PGND PGND PGND PGND 29 31 38 37 PWM DISB# NC CGND GL VSWH VSWH VSWH VSWH VSWH 30 33 41 29 17 VSWH 42 13 40 39 14 28 34 CGND 27 16 VIN 12 26 15 35 11 8 VIN VIN NC PHASE GH CGND BOOT VDRV VCIN SMOD# 36 9 10 13 14 VIN VIN VIN VIN VSWH PGND PGND PGND PGND PGND 25 42 37 VIN VIN VIN VIN VSWH PGND PGND PGND PGND PGND 24 41 12 23 38 VIN 22 9 10 8 7 6 5 4 3 11 CGND 21 40 39 30 PWM DISB# NC CGND GL VSWH VSWH VSWH VSWH VSWH 2 1 SMOD# VCIN VDRV BOOT CGND GH PHASE NC VIN VIN Pin Configuration Bottom View Top View Figure 3. 6mm x 6mm, 40L MLP FDMF6704V Rev. C 2 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Functional Block Diagram Pin Name Function 1 SMOD# 2 VCIN Regulator 5 V Output. Power for gate drives and logic. A minimum 4.7 F X7R ceramic capacitor is required to be connected from this pin to CGND. 3 VDRV Regulator Input Voltage. A minimum 4.7 F X7R ceramic capacitor is required to be connected from this pin to CGND. 4 BOOT Bootstrap Supply Input. Provides voltage supply to high-side MOSFET driver. Connect bootstrap capacitor from this pin to PHASE. 5, 37, 41 CGND IC Ground. Ground return for driver IC. When SMOD# = HI, low side driver is inverse of PWM input. When SMOD# = Low, low side driver is disabled. This pin has no internal pullup or pulldown. It should not be left floating. Do not add noise filter cap. 6 GH For manufacturing test only. This pin must be floated. Must not be connected to any pin. 7 PHASE Switch node pin for easy bootstrap capacitor routing. Electrically shorted to VSWH pin. 8, 38 NC Not Connected Internally. 9-14, 42 VIN Power input. Output stage supply voltage. 15, 29-35, 43 VSWH 16-28 PGND 36 GL For manufacturing test only. This pin must be floated. Must not be connected to any pin. 39 DISB# Output disable. When low, this pin disable FET switching (GH and GL are held low). This pin has no internal pullup or pulldown. It should not be left floating. Do not add noise filter cap. 40 PWM PWM Signal Input. This pin accepts a Tri-state logic-level PWM signal from the controller. Do not add noise filter cap. Switch Node Output. Provides return for high-side bootstrapped driver and acts as a sense point for the adaptive shoot-thru protection. Power Ground. Output stage ground. Source pin of low side MOSFET(s). Absolute Maximum Rating Parameter Min Max Units VCIN, DISB#, PWM, SMOD#, GL to CGND 6 V VIN to PGND, CGND 27 V VDRV to PGND, CGND 16 V BOOT, GH to VSWH, PHASE 6 V BOOT, VSWH, PHASE, GH to GND 27 V BOOT to VCIN 22 V IO(AV)* VIN = 12 V, VO = 1.3 V fSW = 350 kHz 35 A fSW = 1 MHz 32 A IO(peak)* RJB Thermal Resistance Junction to Board Operating and Storage Junction Temperature Range -55 80 A 3.75 C/W 150 C * IO(AV) and IO(peak) are measured in FCS evaluation board. These ratings can be changed with different application setting. Recommended Operating Range Parameter Min Typ Max Units VDRV Vgate and Logic Supply Voltage 8 12 14 V VIN Output FET Supply Voltage 3* 12 14 V * May be operated at lower input voltage. See figure 10. FDMF6704V Rev. C 3 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Pin Description VIN = 12 V, VDRV = 12 V, TA = 25 C unless otherwise noted. Parameter Operating Quiescent Current Symbol IQ Conditions Min Typ Max PWM = GND 2 PWM = VCIN 2 Units mA Internal 5V Regulator Input Voltage VDRV Input Current IVDRV 8V < VIN < 14V, 1MHz 8 Output voltage VCIN VDRV = 8V, ILoad = 5mA Power Dissipation PVDRV VDRV = 12V, 1MHz VCIN Capacitor CVCIN X7R Ceramic Line Regulation 8V < VDRV < 14V, ILoad = 5mA Load Regulation VDRV = 8V, 5mA < ILoad < 100mA 14 36 4.8 5 5.2 250 4.7 V mA V mW 10 20 F mV 75 mV Short Circuit Current Limit 200 mA UVLO Threshold 7.5 V UVLO COMP Hysteresis 0.5 V 10 k PWM Input Sink Impedance PWM to GND Source Impedance PWM to VCIN Tri-State Rising Threshold 10 3.2 Tri-State Rising Hysteresis 3.4 k 3.6 100 Tri-State Falling Threshold 1.2 1.4 V mV 1.6 V Tri-State Falling Hysteresis 100 mV Tri-State Pin Open 2.5 V Tri-State Shut Off Time 100 ns SMOD# and DISB# Input High Level Input Voltage 2 V Low Level Input Voltage Input Bias Current -2 0.8 V 2 A PWM = GND, delay between SMOD# or DISB# from HI to LO to GL from HI to LO. 15 ns 10 % to 90 % 25 ns Fall Time 90 % to 10 % 20 ns Deadband Time tDTHH GL going LO to GH going HI, 10 % to 10 % 25 ns Propagation Delay tPDHL PMW going LO to GH going LO 10 ns 10 % to 90 % 25 ns Fall Time 90 % to 10 % 20 ns Deadband Time tDTLH VSWH going LO to GL going HI, 10 % to 10 % 20 ns Propagation Delay tPDLL PWM going HI to GL going LO 10 ns Delay between GH from HI to LO and GL from LO to HI if VSWH is high. 250 ns Propagation Delay Time High Side Driver Rise Time Low Side Driver Rise Time 250 ns Time Out Circuit 250 ns Time Delay FDMF6704V Rev. C 4 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Electrical Characteristics SMOD# Circuit Description The SMOD (Skip Mode) function allows for higher converter efficiency under light load conditions. During SMOD, the LS FET is disabled and it prevents discharging of output caps. When the SMOD# pin is pulled high, the sync buck converter will work in synchronous mode. When the SMOD# pin is pulled low, the LS FET is turned off. The SMOD function does not have internal current sensing. This SMOD# pin is connected to a PWM controller which enables or disables the SMOD automatically when the controller detects light load condition. This pin is Active Low. The FDMF6704V is a driver plus FET module incorporating an internal 12 V to 5 V regulator that is optimized for synchronous buck converter topology. A single PWM input signal is all that is required to properly drive the high-side and the low-side MOSFETs at speeds up to 1 MHz. PWM When the PWM input goes high, the high side MOSFET turns on. When it goes low, the low side MOSFET turns on. When it is open, both the low side and high side MOFET will turn off. The individual PWM signals from the controller will be used to dynamically enable or disable individual phases. Adaptive Gate Drive Circuit The driver IC embodies an advanced design that ensures minimum MOSFET dead-time while eliminating potential shoot-through (cross-conduction) currents. It senses the state of the MOSFETs and adjusts the gate drive, adaptively, to ensure they do not conduct simultaneously. Refer to Figure 4 for the relevant timing waveforms. DISB# The DISB# input is combined with the PWM signal to control the driver output. In a typical multiphase design, DISB# will be a common signal used to turn on all phases. To prevent overlap during the low-to-high switching transition (Q2 OFF to Q1 ON), the adaptive circuitry monitors the voltage at the GL pin. When the PWM signal goes HIGH, Q2 will begin to turn OFF after some propagation delay (tPDLL). Once the GL pin is discharged below 1 V, Q1 begins to turn ON after adaptive delay tDTHH. Gate Low The low-side driver (GL) is designed to drive a ground referenced low RDS(ON) N-channel MOSFET. The bias for GL is internally connected between VCIN and CGND. When the driver is enabled, the driver's output is 180 out of phase with the PWM input. When the driver is disabled (DISB# = 0 V), GL is held low turning the low side FET off. To preclude overlap during the high-to-low transition (Q1 OFF to Q2 ON), the adaptive circuitry monitors the voltage at the VSWH pin. When the PWM signal goes LOW, Q1 will begin to turn OFF after some propagation delay (tPDHL). Once the VSWH pin falls below 1 V, Q2 begins to turn ON after adaptive delay tDTLH. Gate High The high-side driver (GH) is designed to drive a floating N-channel MOSFET. The bias voltage for the high-side driver is developed by a bootstrap supply circuit, consisting of the internal BOOT diode and an external bootstrap capacitor (CBOOT). During start-up, VSWH is held at PGND, allowing CBOOT to charge to VCIN through the internal diode. When the PWM input goes high, GH will begin to charge the high-side MOSFET's gate (Q1). During this transition, charge is removed from CBOOT and delivered to Q1's gate. As Q1 turns on, VSWH rises to VIN, forcing the BOOT pin to VIN +VC(BOOT), which provides sufficient VGS enhancement for Q1. To complete the switching cycle, Q1 is turned off by pulling GH to VSWH. CBOOT is then recharged to VCIN when VSWH falls to PGND. GH output is in phase with the PWM input. When the driver is disabled, the high-side FET is turned off. Additionally, VGS of Q1 is monitored. When VGS(Q1) is discharged low, a secondary adaptive delay is initiated, which results in Q2 being driven ON after 250 ns, regardless of VSWH state. This function is implemented to ensure CBOOT is recharged each switching cycle, particularly for cases where the power converter is sinking current and VSWH voltage does not fall below the 1 V adaptive threshold. The 250 ns secondary delay is longer than tDTLH. VDRV and VCIN The FDMF6704V incorporates an internal 12 V to 5 V regulator to allow it to be used in single 12 V supply applications. The regulator's 5V output (VCIN) is connected to pin 2 and used internally to supply power to the gate drives and to the internal logic. A 4.7 F X7R ceramic capacitor must be connected between VCIN and ground. This capacitor is part of the regulator's loop compensation so a high X7R type is required. The regulator's input VDRV is connected to pin 3. FDMF6704V Rev. C 5 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Description of Operation FDMF6704V - XSTM DrMOS with Internal 5V Regulator Timing Diagrams tPDHL Timeout PWM GL tPDLL tri-state shutoff tDTLH GH to VSWH tDTHH VSWH Figure 4. Timing Diagram Switch Node Ringing Suppression Fairchild's DrMOS products have proprietary feature* that minimizes the peak overshoot and ringing voltage on the switch node (VSWH) output, without the need of external snubbers. The following pictures show the waveforms of an FDMF6704 DrMOS part and a competitor's part tested without snubbing. The tests were done in the same test circuit, under the same operating conditions. Figure 5. FDMF6704 Figure 6. Competitor Part * Patent Pending FDMF6704V Rev. C 6 www.fairchildsemi.com VIN = 12V, VDRV = 12V, TA = 25C unless otherwise noted. 35 12 30 10 8 PLOSS, W ILOAD, A 25 VIN = 12 V VOUT = 1.3 V L = 440 nH 20 15 fSW = 1 MHz 6 4 10 VIN = 12 V VOUT = 1.3 V fSW = 1 MHz L = 440 nH 5 fSW = 350 kHz 2 0 0 0 25 50 75 100 125 0 150 5 10 15 20 25 30 35 ILOAD, A o PCB Temperature, C Figure 7. Safe Operating Area Figure 8. Module Power Loss vs. Output Current (Note: For total power loss, add 5 V regulator loss shown in Figure 18 on page 8. 1.40 1.14 1.12 1.20 PLOSS (NORMALIZED) PLOSS (NORMALIZED) 1.30 1.16 VIN = 12 V VOUT = 1.3 V IOUT = 30 A L = 440 nH 1.10 1.00 1.10 1.08 1.06 1.04 VOUT = 1.3 V IOUT = 30 A L = 440 nH fSW = 350 kHz 1.02 0.90 1.00 0.80 200 0.98 300 400 500 600 700 800 900 1000 6 8 10 fSW, kHz Figure 9. Normalized Power Loss vs. Switching Frequency 1.040 1.035 PLOSS (NORMALIZED) PLOSS (NORMALIZED) 16 1.045 VIN = 12 V IOUT = 30 A L = 440 nH fSW = 350 kHz 1.20 1.10 1.00 1.030 1.025 1.020 1.015 1.010 1.005 0.90 1.000 0.80 0.8 14 Figure 10. Normalized Power Loss vs. Input Voltage 1.40 1.30 12 Input Voltage, V 1.1 1.4 1.7 2.0 2.3 2.6 2.9 0.995 220 3.2 Output Voltage, V 275 330 385 440 Output Inductance, nH Figure 11. Normalized Power Loss vs. Output Voltage FDMF6704V Rev. C VIN = 12 V VOUT = 1.3 V IOUT = 30 A fSW = 350 kHz Figure 12. Normalized Power Loss vs. Output Inductance 7 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Typical Characteristics VIN = 12V, VDRV = 12V, TA = 25C unless otherwise noted. Driver Supply Current, mA 40 50 V DRV==1212 VRIN VV V VRIN VV DRV==1212 ffSW MHz MHz SW ==1 1 49 Driver Supply Current, mA 45 35 30 25 20 15 10 5 48 47 46 45 44 43 42 41 0 200 300 400 500 600 700 800 900 40 -50 1000 -25 0 fSW, kHz SMOD# Threshold Voltage, V PWM Tri-state Threshold Voltage, V ON STATE 4.0 3.5 3.0 TRI STATE 2.0 1.5 1.0 0.5 150 VVRIN 12 VV DRV==12 2.0 VIH 1.8 1.6 VIL 1.4 1.2 25 85 125 1.0 -50 150 -25 0 o Temperature, C 50 75 100 125 150 o Figure 16. SMOD# Threshold Voltage vs. Temperature 400 VVRIN 12V V DRV ==12 16V Power Dissipation, mW 2.0 VIH 1.8 1.6 VIL 1.4 320 240 12V 160 8V 80 1.2 1.0 -50 25 Temperature, C Figure 15. PWM Tri-state Threshold Voltage vs. Temperature DISB# Threshold Voltage, V 125 OFF STATE 0.0 -40 2.2 100 Figure 14. Driver Supply Current vs. Temperature 2.2 2.5 75 o VVRIN 12 VV DRV==12 4.5 50 Temperature, C Figure 13. Driver Supply Current vs. Frequency 5.0 25 -25 0 25 50 75 100 125 0 200 150 o Temperature, C 400 500 600 700 800 900 1000 Switching Frequency, kHz Figure 17. DISB# Threshold Voltage vs. Temperature FDMF6704V Rev. C 300 Figure 18. Internal 5 V Regulator Power Dissipation vs. Frequency and VDRV Voltage 8 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Typical Characteristics Supply Capacitor Selection Bootstrap Circuit For the supply input (VIN) of the FDMF6704V, a local ceramic bypass capacitor is recommended to reduce the noise and to supply the peak current. Use at least a 4.7 F, X7R or X5R capacitor. Keep this capacitor close to the FDMF6704V VIN and PGND pins. The bootstrap circuit uses a charge storage capacitor (CBOOT), as shown in Figure 19. A bootstrap capacitance of 100nF, X7R capacitor is adequate. A series bootstrap resistor would be needed for specific application in order to improve switching noise immunity. Typical Application Note: For operation with VIN <8V, a separate >8V supply is required for VDRV. VIN 12V VDRV PWM DISB# SMOD# VIN CGND VCIN BOOT RBOOT CBOOT PHASE VSWH PGND FDMF6704V EN SMOD# PWM1 PWM Controller PWM2 VDRV PWM DISB# SMOD# VIN CGND VCIN BOOT RBOOT CBOOT PHASE VSWH PGND FDMF6704V VOUT PWM3 PWM4 CGND Signal GND Power GND VDRV PWM DISB# SMOD# VIN CGND VIN BOOT RBOOT CBOOT PHASE VSWH PGND FDMF6704V VDRV PWM DISB# SMOD# VIN CGND VCIN BOOT PHASE VSWH RBOOT CBOOT PGND FDMF6704V Figure 19. Typical Application FDMF6704V Rev. C 9 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Application Information the FDMF6704V. The resistor and capacitor need to be of proper size for the power dissipation. 5. Place ceramic bypass capacitor and BOOT capacitor as close as possible to the VCIN and BOOT pins of the FDMF6704V to ensure clean and stable power. Routing width and length should be considered as well. Refer to Figure 20 for power loss testing method. Power loss calculation are as follows: (a) (b) (c) (d) (e) (f) (g) PIN PSW POUT PLOSS_MODULE PLOSS_BOARD EFFMODULE EFFBOARD = (VIN x IIN) + (VDRV x IVDRV) = VSW x IOUT = VOUT x IOUT = PIN - PSW = PIN - POUT = 100 x PSW/PIN = 100 x POUT/PIN (W) (W) (W) (W) (W) (%) (%) 6. Include a trace from PHASE to VSWH in order to improve noise margin. Keep the trace as short as possible. 7. The layout should include the option to insert a small value series boot resistor between boot cap and BOOT pin. The boot loop size, including RBOOT and CBOOT, should be as small as possible. The boot resistor is normally not required, but is effective at improving noise operating margin in multi phase designs that may have noise issues due to ground bounce and high negative VSWH ringing. The VIN and PGND pins handle large current transients with frequency components above 100 MHz. If possible, these package pins should be connected directly to the VIN and board GND planes. The use of thermal relief traces in series with these pins is discouraged since this will add inductance to the power path. This added inductance in series with the PGND pin will degrade system noise immunity by increasing negative VSWH ringing. PCB Layout Guideline Figure 21 shows a proper layout example of FDMF6704V and critical parts. All of high current flow path, such as VIN, VSWH, VOUT and GND copper, should be short and wide for better and stable current flow, heat radiation and system performance. Following is a guideline which the PCB designer should consider: 1. Input ceramic bypass capacitors must be close to VIN and PGND pin of FDMF6704V to help reduce the input current ripple component induced by switching operation. 8. CGND pad and PGND pins should be connected by plane GND copper with multiple vias for stable grounding. Poor grounding can create a noise transient offset voltage level between CGND and PGND. This could lead to fault operation of gate driver and MOSFET. 2. The VSWH copper trace serves two purposes. In addition to being the high frequency current path from the DrMOS package to the output inductor, it also serves as heatsink for the lower FET in the DrMOS package. The trace should be short and wide enough to present a low impedance path for the high frequency, high current flow between the DrMOS and inductor in order to minimize losses and temperature rise. Please note that the VSWH node is a high voltage and high frequency switching node with high noise potential. Care should be taken to minimize coupling to adjacent traces. Additionally, since this copper trace also acts as heatsink for the lower FET, tradeoff must be made to use the largest area possible to improve DrMOS cooling while maintaining acceptable noise emission. 9. Ringing at the BOOT pin is most effectively controlled by close placement of the boot capacitor. Do not add an additional BOOT to PGND capacitor. This may lead to excess current flow through the BOOT diode. 10. SMOD#, DISB# and PWM pins don't have internal pull up or pull down resistors. They should not be left floating. These pins should not have any noise filter caps. 11. Use multiple vias on each copper area to interconnect top, inner and bottom layers to help smooth current flow and heat conduction. Vias should be relatively large and of reasonable inductance. Critical high frequency components such as RBOOT, CBOOT, the RC snubber and bypass caps should be located close to the DrMOS module and on the same side of the PCB as the module. If not feasible, they should be connected from the backside via a network of low inductance vias. 3. Output inductor location should be as close as possible to the FDMF6704V to minimize lower power loss due to copper trace. Care should be taken so that inductor dissipation does not heat the DrMOS. 4. The PowerTrench(R) 5 MOSFETs used in the output stage are very effective at minimizing ringing. In most cases, no snubber will be required. If a snubber is used, it should be placed near CVDRV CVCIN IVDRV A CVIN VCIN DISB# PWM Input SMOD# VDRV DISB# VIN CBOOT PHASE VSWH SMOD# CGND VDRV VIN RBOOT BOOT PWM A IIN PGND LOUT V VSW IOUT A VOUT COUT Figure 20. Power Loss Measurement Block Diagram FDMF6704V Rev. C 10 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Power Loss and Efficiency Measurement and Calculation FDMF6704V - XSTM DrMOS with Internal 5V Regulator TOP VIEW BOTTOM VIEW Figure 21. Typical PCB Layout Example FDMF6704V Rev. C 11 www.fairchildsemi.com FDMF6704V - XSTM DrMOS with Internal 5V Regulator Dimensional Outline and Pad layout FDMF6704V Rev. C 12 www.fairchildsemi.com TRADEMARKS The following includes registered and unregistered trademarks and service marks, owned by Fairchild Semiconductor and/or its global subsidiaries, and is not intended to be an exhaustive list of all such trademarks. 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Fairchild will not provide any warranty coverage or other assistance for parts bought from Unauthorized Sources. Fairchild is committed to combat this global problem and encourage our customers to do their part in stopping this practice by buying direct or from authorized distributors. PRODUCT STATUS DEFINITIONS Definition of Terms Datasheet Identification Product Status Advance Information Formative / In Design Preliminary First Production No Identification Needed Full Production Obsolete Not In Production Definition Datasheet contains the design specifications for product development. Specifications may change in any manner without notice. Datasheet contains preliminary data; supplementary data will be published at a later date. Fairchild Semiconductor reserves the right to make changes at any time without notice to improve design. Datasheet contains final specifications. Fairchild Semiconductor reserves the right to make changes at any time without notice to improve the design. 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