SG6846C Fairchild Semiconductor, SG6846C Datasheet
SG6846C
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SG6846C Summary of contents
Page 1
... For over-temperature protection, an external NTC thermistor can be applied to sense the ambient temperature. When OCP, V activated, an internal latch circuit latches off the controller. The latch resets when V SG6846C is available in 8-pin SOP and DIP packages. OCP Latch -20 to +85°C Yes -20 to +85°C ...
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... Typical Application Block Diagram 0.9V/0.7V VIN 3 V -TH-G DD VDD 7 UVLO 16.5V/10.5V 23. 1.05V © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 Figure 1. Typical Application Over Power Compensation 1.18-0. Internal BIAS Latch Debounce OCP Delay 1 GND Figure 2. Block Diagram VDD Soft ...
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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 110ms, SG6846C 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 © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 Parameter DIP <50°C A SOP DIP SOP ...
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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 Start up Time t SS-130KHz © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 Test Condition Min. 15.5 9 – 0.16V DD-ON GATE Open 22 26kΩ 60 ...
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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 © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 (Continued) Test Condition Center Frequency R = 26kΩ Jitter Range Center Frequency R = 13kΩ Jitter Range ...
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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 © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 (Continued) Test Condition V = 15V 12V GATE = 1nF GATE = 1nF V = 20V DD ( 26kΩ ...
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... VIN=1V) vs Temperature 0.60 0.58 0.56 0.54 0.52 0.50 -40 -25 - Temperature (℃ ) Figure 10. OCP Threshold Voltage for Current Limit ( 1V) vs. Temperature STH1V 1/2 IN © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1 11.5 11.0 10.5 10.0 9.5 9 110 125 -40 ) Figure 7. Turn-off Threshold Voltage (V DD- erat ure 4.0 3.5 3.0 2 ...
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... urn hres olt perat u re 0.910 0.905 0.900 0.895 0.890 -40 -25 - perat u re (℃ ) Figure 16. PWM Turn-on Threshold Voltage (V vs. Temperature © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 (Continued perat ure 87.0 86.8 86.6 86.4 86.2 86 110 125 -40 ) Figure 13 ...
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... This green-mode function dramatically consumption under light-load and zero-load conditions. Power supplies using the SG6846C can meet even the most restrictive international regulations regarding standby power consumption. Oscillator Operation A resistor connected from the RI pin to GND generates a reference current source, inside the SG6846C, used to determine the PWM frequency ...
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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 SG6846C. © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 (Continued) Slope compensation 11 Figure 18 ...
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... 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% © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 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/ © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1 Figure 20 ...
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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/ © 2007 Fairchild Semiconductor Corporation SG6846C • Rev. 1.1 ...
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... Fairchild Semiconductor Corporation SG6846C • Rev. 1.1.2 15 www.fairchildsemi.com ...