FDMF6823B Fairchild Semiconductor, FDMF6823B Datasheet
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FDMF6823B
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FDMF6823B Summary of contents
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... A thermal warning function warns of a potential over-temperature situation. The FDMF6823B also incorporates a Skip Mode (SMOD#) for improved light-load efficiency. The FDMF6823B also provides a 3-state 5V PWM input for compatibility with a wide range of PWM controllers. Applications High-Performance Gaming Motherboards ...
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... UVLO DISB# 10µA V CIN R UP_PWM Input PWM 3- State Logic R DN_PWM THWN# Temp. Sense CGND © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 VDRV VCIN VIN R BOOT DISB# BOOT PWM FDMF6823B PHASE SMOD# VSWH THWN# PGND CGND Figure 1. Typical Application Circuit VDRV ...
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... LOW). This pin has a 10µA internal pull-down current source. Do not add a noise filter capacitor. 40 PWM PWM signal input. This pin accepts a three-state 5V PWM signal from the controller. © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 Figure 4. Top View Description 3 www.fairchildsemi.com ...
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... MOSFET switching transients. For reliable DrMOS operation, VSWH-to-GND and BOOT-to-GND must remain at or below the Absolute Maximum Ratings shown in the table above. Refer to the “Application Information” and “PCB Layout Guidelines” sections of this datasheet for additional information. © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 Parameter Referenced to CGND Referenced to CGND ...
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... High-Level Input Voltage IH_SMOD V Low-Level Input Voltage IL_SMOD I Pull-Up Current PLU t Propagation Delay PD_SLGLL t Propagation Delay PD_SHGLH © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0 5V, and +25°C unless otherwise noted. CIN DRV A J Condition PWM=LOW or HIGH or Float Q VCIN ...
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... PD_PHGLL Delay Exiting 3-State Propagation t PD_TSGLH Delay Boot Diode V Forward-Voltage Drop F V Breakdown Voltage R © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0 5V, and +25°C unless otherwise noted. CIN DRV A J Condition I =5mA PLD SW=0V, Delay Between GH from HIGH to LOW and GL from LOW to HIGH = 30A +25° ...
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... V IH_PWM PWM VSWH VSWH t PD_PHGLL t D_DEADON © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 90% 1.0V 10 PLGHL Figure 5. PWM Timing Diagram 7 V IL_PWM 10% 90% 1.2V t D_TIMEOUT ( 250ns Timeout) 2.2V t D_DEADOFF www.fairchildsemi.com ...
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... Module Switching Frequency, F Figure 8. Power Loss vs. Switching Frequency 1. 12V 1V 300kHz OUT SW 1.10 1.05 1.00 0.95 0.90 4.0 4.5 Driver Supply Voltage, V Figure 10. Power Loss vs. Driver Supply Voltage © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 =1V, V =5V, V =5V, L =250nH, T CIN DRV OUT 1000kHz ...
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... Driver Supply Voltage, V Figure 14. Driver Supply Current vs. Driver Supply Voltage 3.2 3.1 3.0 2.9 2.8 2.7 2.6 - Driver IC Junction Temperature, T Figure 16. UVLO Threshold vs. Temperature © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 =1V, V =5V, V =5V, L =250nH, T CIN DRV OUT 60 = 300kHz 1V 30A SW OUT OUT 100 ...
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... Driver IC Junction Temperature, T Figure 20. SMOD# Threshold vs. Temperature 2 25°C A 2.0 1.8 1.6 1.4 1.2 4.50 4.75 5.00 Driver IC Supply Voltage, V Figure 22. DISB# Threshold vs. Driver Supply Voltage © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 =5V, T =25°C, and natural convection cooling, unless otherwise specified. A 2.2 V IH_PWM 2.0 V TRI_HI 1.8 V HIZ_PWM 1.6 V TRI_LO 1.4 V IL_PWM 1.2 ...
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... DRV 12 CIN 11.5 11.0 10.5 10.0 9.5 9.0 - Driver IC Junction Temperature, T Figure 24. DISB# Pull-Down Current vs. Temperature © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 =5V, T =25°C, and natural convection cooling, unless otherwise specified. A 500 450 400 350 300 250 200 150 100 55 100 125 150 ( o ...
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... PWM input goes from three-state to LOW, the low-side MOSFET is turned on. If the PWM input goes from Driver State three-state to HIGH, the high-side MOSFET is turned on. This is illustrated in Figure 27. The FDMF6823B design allows for short propagation delays when exiting the three-state window (see Electrical Characteristics). Low-Side Driver ...
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... PD_SHGLH GS IH_SMOD © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 HIGH, Q2 begins to turn off after a propagation delay (t PD_PHGLL Q1 begins to turn on after adaptive delay t To preclude overlap during the HIGH-to-LOW transition (Q1 off to Q2 on), the adaptive circuitry monitors the voltage at the GH-to-PHASE pin pair ...
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... D_DEADOFF D_DEADON © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 When the SMOD# pin is pulled HIGH, the synchronous buck converter works in Synchronous Mode. This mode allows for gating on the Low Side MOSFET. When the SMOD# pin is pulled LOW, the low-side MOSFET is gated off ...
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... ON Open - Drain Output © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 VCIN Filter The VDRV pin provides power to the gate drive of the high-side and low-side power MOSFET. In most cases, it can be connected directly to VCIN, the pin that provides power to the logic section of the driver. For additional noise immunity filter can be inserted between the VDRV and VCIN pins ...
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... MOSFET, balance using the largest area possible to improve DrMOS cooling while maintaining acceptable noise emission output inductor should be located close to the FDMF6823B to minimize the power loss due to the V copper trace. Care should also be taken so the SWH inductor dissipation does not heat the DrMOS. ® ...
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... Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 Figure 31. PCB Layout Example (Top View) Figure 32. PCB Layout Example (Bottom View) 17 www.fairchildsemi.com ...
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... Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically the warranty therein, which covers Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2011 Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 B PIN#1 INDICATOR 6. ...
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... Fairchild Semiconductor Corporation FDMF6823B • Rev. 1.0.2 19 www.fairchildsemi.com ...