ld7575a Leadtrend Technology, ld7575a Datasheet
ld7575a
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ld7575a 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 LD7575A 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 LD7575A PS LD7575A GS LD7575A PN The LD7575A is ROHS Complaint/ Green Package. 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), 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 LD7575A-DS-00a November 2007 HV 1mA internal bias & Vref VCC OK Vref OK PWM Comparator ∑ Slope Compensation + OCP 0.85V Comparator 30mS Delay ...
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... Recommended Operating Conditions Item Supply Voltage Vcc Vcc Capacitor Switching Frequency Leadtrend Technology Corporation LD7575A-DS-00a November 2007 Min. Max ...
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... 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 LD7575A-DS-00a November 2007 =15.0V) CC CONDITIONS Vcc< UVLO(on), HV=500V Vcc> ...
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... Temperature (°C) Fig Current Source vs. Temperature (HV=500V, Vcc=0V) 18.0 17.2 16.4 15.6 14.8 14.0 - Temperature (°C) Fig. 3 UVLO (on) vs. Temperature - Temperature (°C) Fig. 5 Frequency vs. Temperature Leadtrend Technology Corporation LD7575A-DS-00a November 2007 0.90 0.89 0.88 0.87 0.86 0.85 80 120 125 -40 12 11.2 10.4 9.6 8 120 125 - ...
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... Fig. 7 Frequency vs. Vcc - Temperature ( ° C) Fig. 9 Max Duty vs. Temperature 7.0 6.5 6.0 5.5 5.0 4.5 - Temperature ( ° C) Fig open loop voltage vs. Temperature COMP Leadtrend Technology Corporation LD7575A-DS-00a November 2007 120 125 -40 6.0 5.5 5.0 4.5 4.0 3 ...
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... Whenever the Vcc voltage is higher than UVLO(on) to power on the LD7575A 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 ...
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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 LD7575A 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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... On/Off Control The LD7575A can be controlled to turn off by pulling COMP pin to lower than 1.2V. The gate output pin of LD7575A will be disabled immediately under such condition. The off mode can be released when the pull-low signal is removed. Dual-Oscillator Green-Mode Operation ...
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... The Vcc OVP function in LD7575A is an auto-recovery type protection. If the OVP condition, usually caused by the feedback loop opened, is not released, the Vcc will tripped the OVP level again and re-shutdown the output. The Vcc is working as a hiccup mode. operation. On the other hand, if the OVP condition is removed, the Vcc level will get back to normal level and the output is automatically returned to the normal operation ...
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... Thanks to the Leadtrend’s proprietary Hi-V technology, there is no such parasitic SCR in LD7575A. shows the equivalent circuit of LD7575A’s Hi-V structure. So that LD7575A is with higher capability to sustain negative voltage than similar products. However, a 10KΩ resistor is recommended to implement on the Hi-V path to Leadtrend Technology Corporation ...
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... Reference Application Circuit --- 10W (5V/2A) Adapter Schematic Leadtrend Technology Corporation LD7575A-DS-00a November 2007 Pin < 0.15W when Pout = 0W & Vin = 264Vac 13 www.leadtrend.com.tw LD7575A ...
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... 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 LD7575A-DS-00a November 2007 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 LD7575A-DS-00a November 2007 Dimensions in Millimeters MIN MAX 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 0.254 0.004 5 ...
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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 LD7575A-DS-00a November 2007 Dimension in Millimeters Dimensions in Inches Min ...
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... Revision History Rev. Date Change Notice 00 1/8/2007 Original Specification. 00a 11/29/2007 Green Package option. Leadtrend Technology Corporation LD7575A-DS-00a November 2007 17 www.leadtrend.com.tw LD7575A ...