SG6846ALSZ Fairchild Semiconductor, SG6846ALSZ Datasheet
SG6846ALSZ
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SG6846ALSZ Summary of contents
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... Number Temperature Range SG6846ALSY -40 to +105°C SG6846ACSY -40 to +105°C SG6846ALSZ -40 to +105°C For Fairchild’s definition of “green” Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html. © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 Description The SG6846A is especially designed for SMPS with surge-current output, incorporated with a two-level OCP function ...
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... Typical Application Block Diagram © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 Figure 1. Typical Application Figure 2. Block Diagram 2 www.fairchildsemi.com ...
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... Marking Information SG6846AFTP XXXXXXXXYWWV *The “Top Mark 2” is the updated mark. © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1 OCP Latch SOP Lead Free + ROHS Compatible Null = regular package XXXXXXXX: Wafer Lot Y: Year; WW: Week V: Assembly Location Figure 3. Top Mark 1 : Fairchild logo ...
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... VDD Power Supply 8 GATE Driver Output © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 Figure 5. Pin Configuration Description Ground. The signal from the external compensation circuit is fed into this pin. The PWM duty cycle is determined in response to the signal from this pin and the current- sense signal from pin 6 ...
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... The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not recommend exceeding them or designing to Absolute Maximum Ratings. Symbol T Operating Ambient Temperature A © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 Parameter <50°C SOP A SOP ...
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... OCP Threshold Voltage for Current Limit STH3V-2/3 t Delay Time for Over-Current Protection D-OCP Delay Time for Output Short-Circuited t D-SCP Protection t SS-65KHz Period During Startup Time t SS-130KHz © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 Test Condition Min. 15.5 9 DD-OFF +0. – 0.16V DD-ON GATE Open 22 ...
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... FB Voltage at f FB-G OSC-G S Slope for Green-Mode Modulation G f Frequency Variation vs Frequency Variation vs. Temperature f DT Deviation © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1 Timing = 1700 ms OCP Figure 6. SG6846A OCP/SCP Logic Flow Diagram (Continued) Test Condition Center Frequency R = 26kΩ, V ...
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... Operating Range NOR I RI Maximum R Value for Protection MAX I RI Minimum R Value for Protection MIN I Note: 1. The relationship between R © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1 FB-G FB-N Figure 7. PWM Frequency (Continued) Test Condition V = 15V 12V GATE = 1nF GATE = 1nF ...
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... Temperature (℃) Figure 10. Startup Current (I 2.5 2.0 1.5 1.0 0.5 0.0 -40 - 109 125 Temperature ( ℃ ) Figure 12. PWM Turn-off Threshold Voltage (V vs. Temperature © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 11.5 11.1 10.7 10 110 125 ) Figure 9. Turn-off Threshold Voltage (V DD- ...
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... VIN ( V ) Figure 16. Current-Limit Threshold vs. V 71.0 70.5 70.0 69.5 69.0 68.5 -40 -25 - 110 125 Temperature (℃) Figure 18. Output Current of RT Pin (I vs. Temperature © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 (Continued 110 125 ) Figure 15 ...
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... PWM Ω © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1 open-circuit or short-circuit to ground occurs at the RI pin, the internal protection circuit immediately shuts down the controller. Two-level Over-current Protection (OCP) The cycle-by-cycle current limiting shuts down the PWM before immediately when the switching current is over the DD peak-current threshold ...
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... Good placement and layout practices should be followed. Avoid long PCB traces and component leads. Compensation and filter components should be located near the SG6846A. © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 (Continued) Slope compensation 12 Figure 20 ...
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... R7 27KΩ +/-5% R6 330Ω +/-1% R19 102KΩ +/-1% R14 0Ω22 +/-5% R16, R17 1W 20Ω +/-5% R11 20KΩ +/-5% R12 100KΩ +/-5% R20 887KΩ +/-1% R22 10KΩ +/-1% © 2008 Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 BD1 LF2 CX2 R12 ...
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... Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or obtain the most recent revision. 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’ ...
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... Fairchild Semiconductor Corporation SG6846A • Rev. 1.1.4 15 www.fairchildsemi.com ...