FAN1577A Fairchild Semiconductor, FAN1577A Datasheet
FAN1577A
Related parts for FAN1577A
FAN1577A Summary of contents
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... The fixed-frequency is programmable from 61kHz to 340kHz. The Over-Current Protection (OCP) level can be programmed by an external current-sense resistor. It has two integrated sets of internal MOSFET drivers. FAN1577A is available in a 20-pin small-outline package (SOP). -40°C to +85°C 20-Lead, Small-Outline Package October 2010 ...
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... Application Diagram Internal Block Diagram © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Figure 1. Typical Application Figure 2. Functional Block Diagram 2 www.fairchildsemi.com ...
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... Compensation IN2 19 Feedback GND 20 Analog Ground The reference of internal control circuits. © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 F: Fairchild Logo T: Assembly Plant Code A: Year Code H: Week Code AA: Die Run Code Figure 4. Marking Legend Description An external resistor connecting this pin to GND can program the switching frequency ...
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... Fairchild does not recommend exceeding them or designing to absolute maximum ratings. Symbol V Supply Voltage CC T Operating Ambient Temperature A © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Parameter Human Body Model (HBM) Charged Device Model (CDM) Parameter 4 Min. Max. Unit 16 ...
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... Total Operating Current I Operating Supply Current CC_OP I Standby Current (Disabled) CC_SBY Notes: 1. Not tested in production; 30 pieces sampled. 2. When V falls less than 2V relative © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Conditions V Ramp- Ramp-Down CC R =OPEN RT R =GND RT 20kΩ＜R ...
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... Timing Diagram © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Figure 6. Timing Chart of Two-Stage Soft-Start 6 www.fairchildsemi.com ...
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... Typical Characteristics Figure 7. f vs. Temperature SW Figure 9. Operating Current vs. Temperature Figure 11. First Soft-Start Charge © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Figure 8. V vs. Temperature CC_ON Figure 10. Internal Reference Voltage (V vs. Temperature Figure 12. Over-Current Sink Current (I vs. Temperature 7 ) REF ) OCSET www.fairchildsemi.com ...
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... Typical Performance Characteristics Unless otherwise noted, values are for V Figure 13. Power On at 0.3A Load Figure 15. Power Load Figure 17. Power Off with 0.3A Load © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 =12V, T =+25°C, C =150nF, and SS1/ENB Figure 14. Power On at 3.6A Load Figure 16 ...
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... Typical Performance Characteristics Unless otherwise noted, values are for V Figure 19. Phase Shift at 0.3A Load Figure 21. Dead Time at 0.3A Load (Rising Edge) Figure 23. Dead Time at 18A Load (Rising Edge) © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 (Continued) =12V, T =+25°C, C =150nF, and C CC ...
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... Unless otherwise noted, values are for V Figure 25. Load Transient Response (Step-Up) 20kΩ/22nF in Compensation Loop Figure 27. Over-Current Protection (OCP) Figure 29. Over-Voltage Protection (OVP) © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 (Continued) =12V, T =+25°C, C =150nF, and SS1/ENB Figure 26. Load Transient Response (Step-Down) 20kΩ ...
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... SS2 t μ 4 Setting the Output Voltage 35 A The FAN1577A can be set from 0. output voltages are independently adjusted by voltage dividers (R external resister dividers can be calculated by: V OUT Output Driver The bootstrapping circuit to provide the required boost voltage. The highest gate driver’s output (15V is the ...
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... Type II Compensation Design (for Output Capacitors with High ESR) FAN1577A is a voltage-mode controller. The control loop is a single-voltage feedback path, including an error amplifier and PWM comparator, as shown in Figure 30. To achieve fast transient response and accurate output regulation, an adequate compensator design is necessary. A stable control loop has a 0dB gain crossing with -20dB/decade slope and a phase margin greater than 45° ...
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... INx and COMPx pins). Position those components close to their pins with a local, clear, GND connection or directly to the ground plane. © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 Place the bootstrap capacitor near the BSTx and CLNx pins. The resistor on the RT pin should be near this pin ...
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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/. © 2010 Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 13.00 12.60 A 11.43 ...
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... Fairchild Semiconductor Corporation FAN1577A • Rev. 1.0.0 15 www.fairchildsemi.com ...