ld7575b Leadtrend Technology, ld7575b Datasheet
ld7575b
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ld7575b Summary of contents
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... AC/DC power applications. Furthermore, the embedded over voltage protection, over load protection and the special green-mode control provide the solution for users to design a high performance power circuit easily. The LD7575B is offered in both SOP-8 and DIP-8 package. Typical Application Leadtrend Technology Corporation ...
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... Pin Configuration Ordering Information Part number LD7575B GS LD7575B GN LD7575B PS LD7575B PN The LD7575B is ROHS Complaint. Pin Descriptions PIN NAME This pin is to program the switching frequency. By connecting a resistor to ground set the switching frequency. Voltage feedback pin (same as the COMP pin in UC384X), By connecting a ...
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... Block Diagram UVLO 32V Comparator 16.0V/ 10. OSC Green-Mode Control Vbias COMP Leading CS Edge Blanking 5.0V OLP Comparator Leadtrend Technology Corporation LD7575B-DS-00 May 2008 HV 1mA internal bias & Vref VCC OK Vref OK PWM Comparator ∑ Slope Compensation + OCP 0.85V Comparator 30mS Delay /2 PG ...
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... Recommended Operating Conditions Item Supply Voltage Vcc Vcc Capacitor Switching Frequency Leadtrend Technology Corporation LD7575B-DS-00 May 2008 30V -0.3V~500V -0.3 ~7V 150°C -20°C to 85°C -65°C to 150°C 160°C/W 100° ...
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... OLP Trip Level OLP Delay Time (note) Note: The OLP delay time is proportional to the period of switching cycle. So that, the lower RT value will set the higher switching frequency and the shorter OLP delay time. Leadtrend Technology Corporation LD7575B-DS-00 May 2008 =15.0V) CC CONDITIONS Vcc< UVLO(on), HV=500V Vcc> ...
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... Temperature (°C) Fig. 3 UVLO (on) vs. Temperature Temperature (°C) Fig. 5 Frequency vs. Temperature Leadtrend Technology Corporation LD7575B-DS-00 May 2008 0.90 0.88 0.86 0.84 0.82 0.80 120 125 80 -40 10. 8 10. 6 10. 4 10. 2 10. 0 9.8 9.6 9.4 9.2 9.0 8 100 120 24 23 ...
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... Temperature ( ° C) Fig. 9 Max Duty vs. Temperature 6.6 6.4 6 5.8 5.6 5.4 5.2 5.0 -40 - Temperature ( ° C) Fig open loop voltage vs. Temperature COMP Leadtrend Technology Corporation LD7575B-DS-00 May 2008 100 120 -40 6.0 5.5 5.0 4.5 4.0 3 100 120 ...
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... Whenever the Vcc voltage is higher than UVLO(on) to power on the LD7575B and further to deliver the gate drive signal, the high-voltage current source is off and the supply current is provided from the auxiliary winding of the transformer. Therefore, the power losses on the startup circuit can be eliminated and the power saving can be easily achieved ...
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... The typical current mode PWM controller feedbacks both current signal and voltage signal to close the control loop and achieve regulation. The LD7575B detects the primary MOSFET current from the CS pin, which is not only for the peak current mode control but also for the pulse-by-pulse current limit ...
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... LD7575B, the internal slope compensation circuit has been implemented to simplify the external circuit design. On/Off Control The LD7575B can be controlled to turn off by pulling COMP pin to lower than 1.2V. The gate output pin of LD7575B will Leadtrend Technology Corporation LD7575B-DS-00 May 2008 be disabled immediately under such condition. The off mode can be released when the pull-low signal is removed ...
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... A lot of protection features have been implemented in the LD7575B to prevent the power supply or adapter from being damaged caused by single fault condition on the open or short condition on the pin of LD7575B. Under the conditions listed below, the gate output will be off immediately to protect the power circuit --- ...
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... Thanks to the Leadtrend’s proprietary Hi-V technology, there is no such parasitic SCR in LD7575B. shows the equivalent circuit of LD7575B’s Hi-V structure. So that LD7575B is with higher capability to sustain negative voltage than similar products. However, a 40KΩ resistor is recommended to implement on the Hi-V path to be played the role as a current limit resistor whenever a negative voltage is applied in any case ...
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... Reference Application Circuit --- 10W (5V/2A) Adapter Schematic Leadtrend Technology Corporation LD7575B-DS-00 May 2008 Pin < 0.15W when Pout = 0W & Vin = 264Vac 13 LD7575B ...
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... R53 2.49KΩ, 0805, 1% R54 100Ω, 0805 R55 1KΩ, 0805 R56A 2.7KΩ, 1206 R56B N/A NTC1 5Ω, 3A FL1 20mH T1 EI-22 L51 2.7μH Leadtrend Technology Corporation LD7575B-DS-00 May 2008 Original P C51 C52 C54 C55 CX1 CY1 D1A D1B D1C D1D D2 D4 ...
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... Package Information SOP-8 Symbols θ Leadtrend Technology Corporation LD7575B-DS-00 May 2008 Dimensions in Millimeters Dimensions in Inch MIN MAX MIN 4.801 5.004 0.189 3.810 3.988 0.150 1.346 1.753 0.053 0.330 0.508 0.013 1.194 1.346 0.047 0.178 0.229 0.007 0.102 ...
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... Important Notice Leadtrend Technology Corp. reserves the right to make changes or corrections to its products at any time without notice. Customers should verify the datasheets are current and complete before placing order. Leadtrend Technology Corporation LD7575B-DS-00 May 2008 Dimension in Millimeters Dimensions in Inches Min Max Min 9 ...
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... Revision History Rev. Date Change Notice 00 5/26/2008 Original Specification. Leadtrend Technology Corporation LD7575B-DS-00 May 2008 17 LD7575B ...