SG6846G Fairchild Semiconductor, SG6846G Datasheet
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SG6846G
Related parts for SG6846G
SG6846G Summary of contents
Page 1
... UVLO lower limit. This green-mode function enables power supplies to meet international power conservation requirements. The SG6846G is designed for SMPS with surge-current output, incorporated with a two-level OCP function. Besides the cycle-by-cycle current limiting; if the switching current is higher than OCP threshold and lasts for 500ms, SG6846G shuts down immediately ...
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... Filter N VIN SG6846G Block Diagram 0.9V/0.7V VIN 3 V -TH-G DD VDD 7 UVLO 16.5V/10.5V 23. 1.05V © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0 VDD GATE 8 SENSE 6 GND Figure 1. Typical Application Over Power Compensation 1.18-0. Internal BIAS Latch Debounce OCP ...
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... Current sense. The sensed voltage is used for peak-current-mode control and cycle-by-cycle current limiting. If the switching current is higher than OCP threshold and lasts for 500ms, SG6846G turns off immediately. This two-level OCP feature is especially suitable for SMPS with surge current output. ...
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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 SG6846G • Rev. 1.0.2 Parameter <50°C A Parameter 4 Min. Max. ...
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... OCP Threshold Voltage for Current Limit STH1V-1/2 V OCP Threshold Voltage for Current Limit STH3V-1/2 t Delay Time for Over-Current Protection D-OCP t SS-65KHz Period During Startup Time t SS-130KHz © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 Test Condition Min. 15.5 9 – 0.16V DD-ON GATE Open 26kΩ 60 ...
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... Slope for Green-Mode Modulation Threshold Voltage for Zero Duty Cycle FB-ZDC f Frequency Variation vs Frequency Variation vs. Temperature f DT Deviation © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 (Continued) Test Condition Center Frequency R = 26kΩ Jitter Range Center Frequency R = 13kΩ, 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 SG6846G • Rev. 1.0.2 (Continued) Test Condition V = 15V 12V GATE = 1nF GATE = 1nF V = 20V DD ( 26kΩ ...
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... Temperature (℃ ) Figure 10. OCP Threshold Voltage for Current Limit ( 1V) vs. Temperature STH1V 1/2 IN © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 11.5 11.0 10.5 10.0 9.5 9 125 ) Figure 7. Turn-off Threshold Voltage (V DD- ...
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... 0.9 10 0.9 05 0.9 00 0 (℃ ) Figure 16. PWM Turn-on Threshold Voltage (V vs. Temperature © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 (Continued) 8 7.0 8 6.8 8 6.6 8 6.4 8 6 Figure 13 ...
Page 10
... Over-Temperature Protection (OTP) (2) An external NTC thermistor can be connected from the RT pin to GND. The impedance of the NTC decreases at high temperatures. When the voltage of the RT pin drops below 1.05V, the SG6846G is turned off. For protection-mode options, see Ordering Information 26kΩ), the I voltage ...
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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 SG6846G. © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 (Continued) Slope compensation 11 Figure 18 ...
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... R14 0Ω22 ±5% R16, R17 1W 20Ω ±5% R11 20KΩ ±5% R12 100KΩ ±5% R20 887KΩ ±1% R22 10KΩ ±1% © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 BD1 LF2 CX2 R12 ...
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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/. © 2008 Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 5.00 4.80 A 3.81 ...
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... Fairchild Semiconductor Corporation SG6846G • Rev. 1.0.2 14 www.fairchildsemi.com ...