FAN2108 Fairchild Semiconductor, FAN2108 Datasheet
FAN2108
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FAN2108 Summary of contents
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... For Fairchild’s definition of Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html. © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 Description The FAN2108 TinyBuck™ highly efficient, small footprint, 8A, synchronous buck regulator. IN The FAN2108 contains both synchronous MOSFETs and a controller/driver with optimized interconnects in ...
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... Typical Application Block Diagram © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 Figure 1. Typical Application Diagram Figure 2. Block Diagram 2 www.fairchildsemi.com ...
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... No Connect. This pin is not used. Ramp Amplitude. A resistor (R 25 RAMP and provides voltage feedforward functionality. © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 ) from this pin to AGND can be used to program the current- ILIM ) from this pin to AGND sets the PWM switching T ) connected from this pin to V ...
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... Power Dissipation Note: 1. Typical thermal resistance when mounted on a four-layer, two-ounce PCB, as shown in Figure 24. Actual results are dependent on mounting method and surface related to the design. © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 Conditions Conditions VCC to AGND VIN to PGND FAN2108MPX FAN2108EMPX ...
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... Fault Discharge Hysteresis FLT_HYS Soft-Start Regulation (T0.8) SS OUT t Fault Enable/SSOK (T1.0) EN Note: 2. Specifications guaranteed by design and characterization; not production tested. © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 Conditions SW=Open, FB=0.7V =600KHz SW Shutdown: EN= Rising V CC Hysteresis R =50KΩ =24KΩ ...
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... R EN Pull-Up Resistance Discharge Current Drive Resistance FB V PGOOD Threshold PG V PGOOD Output Low PG_L © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 (Continued) Conditions Auto-Restart Mode FB < V REF FB > V REF I < 2mA OUT 6 Min. Typ. Max. Unit 1.35 2.00 ...
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... Figure 4. Reference Voltage (V vs. Temperature, Normalized 1500 1200 900 600 300 Figure 6. Frequency vs. R 1.4 1.2 1 0.8 0.6 -50 0 Temperature (°C) Figure 8. R vs. Temperature, Normalized © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 1.20 1.10 1.00 0.90 0.80 50 100 150 - 1.02 1.01 1.00 0.99 0.98 -50 80 100 120 140 (K Ω Figure 7. T 1.04 1.02 Q1 ~0.32%/° ...
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... Efficiency Over V OUT Efficiency@ Vin=12V, Vo=1. Load Current (A) Figure 13. 1.8V Efficiency Over Frequency OUT vs. Load © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 Figure 10. Application Circuit: 1. 100 vs. Load Figure 12. 3.3V IN 0.8012 0.801 ...
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... Figure 15. Startup, 3A Load V PGOOD EN Figure 17. Shutdown, 1A Load V OUT I OUT Figure 19. Transient Response, 2-8A Load © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 (Continued) V OUT PGOOD Figure 16. Startup with 1V Pre-Bias on V OUT Figure 20. MOSFET Temperature – Still Air at Room 9 =12V, V =5V, unless otherwise specified. ...
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... If the parallel combination of R1 and R internal SS ramp is not released and the regulator does not start. Bias Supply The FAN2108 requires a 5V supply rail to bias the IC and provide gate-drive energy. Connect a ≥ 1.0µf X5R or X7R decoupling capacitor between VCC and PGND. Since V ...
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... KHz. Setting the Current Limit There are two levels of current-limit thresholds in FAN2108. The first level of protection is through an internal default limit set at the factory to limit output current beyond normal usage levels. The second level of protection is externally settable at the ILIM pin. ...
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... After a fault, EN pin is discharged by a 1µA current sink to a 1.1V threshold before the internal 800KΩ pull-up is restored. A new soft-start cycle begins when EN charges above 1.35V. Depending on the external circuit, the FAN2108 can be configured to remain latched-off or to automatically restart after a fault. Table 1. Fault / Restart Configurations ...
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... Fairchild products. Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings: http://www.fairchildsemi.com/packaging/. © 2008 Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 2X ALL VALUES TYPICAL EXCEPT WHERE NOTED A) DIMENSIONS ARE IN MILLIMETERS. B) DIMENSIONS AND TOLERANCES PER ...
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... Fairchild Semiconductor Corporation FAN2108 • Rev. 1.0.1 14 www.fairchildsemi.com ...