ld7577ja Leadtrend Technology, ld7577ja Datasheet
ld7577ja
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ld7577ja Summary of contents
Page 1
... It provides functions of low startup current, green-mode power-saving operation, leading-edge blanking of the current sensing and internal slope compensation. Also, the LD7577JA features more protections like OLP (Over Load Protection), OVP (Over Voltage Protection), and brownout protection to prevent the circuit being damaged from the abnormal conditions. ...
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... Pin Configuration SOP-8 & DIP-8 (TOP VIEW TOP MARK YYWWPP 1 2 Ordering Information Part number Switching Freq. LD7577JA GR LD7577JA GS LD7577JA GN Note: The LD7577JA is Green packaged. Pin Descriptions SOP-8 SOP-7 NAME DIP BNO 2 2 COMP GND 5 5 OUT ...
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... Block Diagram Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 3 www.leadtrend.com.tw LD7577JA ...
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... Stresses beyond the ratings specified in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 4 www.leadtrend.com.tw LD7577JA -0 ...
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... Maximum Input Voltage(Vcs_off) Leading Edge Blanking Time Input impedance Delay to Output Oscillator for Switching Frequency Frequency Trembling Frequency Green Mode Frequency Modulation Frequency Temp. Stability Voltage Stability Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 =15.0V) CC CONDITIONS V < UVLO(on), HV=500V CC V > UVLO(off), HV=500V CC V =0V,Fsw=65KHz ...
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... Output High Level Rising Time Falling Time OLP (Over Load Protection) OLP Trip Level OLP Delay Time De_Latch VCC Level Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 IBNO=1.5μA VCC=15V, Io=20mA VCC=15V, Io=20mA Load Capacitance=1000pF Load Capacitance=1000pF Fsw=65KHz PDR (Power Down Reset) 6 www ...
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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 LD7577JA-DS-00b November 2009 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 LD7577JA-DS-00b November 2009 120 125 -40 6.0 5.5 5.0 4.5 4.0 3 ...
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... Vcc voltage is lower than the UVLO(off) threshold thus the current source supply a current of 1mA. Meanwhile, the Vcc current consumed by the D1 LD7577JA is as low as 320μA thus most of the HV current is utilized to charge the Vcc capacitor. By using such C1 configuration, the turn-on delay time will be almost the same no matter whether operation condition is under low-line or high-line ...
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... An UVLO comparator is included to detect the voltage on the V pin to ensure the supply voltage is high enough to CC power on the LD7577JA PWM controller and in addition to drive the power MOSFET. As shown in Fig. 15, a Hysteresis is provided to prevent the shutdown caused by the voltage dip during startup. The turn-on and turn-off threshold levels are set at 16V and 10 ...
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... LD7577JA, the internal slope compensation circuit has been implemented to simplify the external circuit design. On/Off Control Pulling COMP pin below 1.2V will turn off the LD7577JA and disable the gate output pin of the LD7577JA. The off-mode will be released when the pull-low signal at COMP pin is removed ...
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... Over Load Protection (OLP) To protect the circuit from being damaged under over load condition or short condition, a smart OLP function is built in with the LD7577JA, as shown in Figure 18 shows the waveforms of the OLP operation. If output voltage drops, the feedback system tends to force the voltage loop toward the saturation (5 ...
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... Switching Fig. 19 Brownout Protection & Line voltage OVP (Over voltage protection) The LD7577JA is programmable to set the brownout protection point and the line voltage OVP point though BNO pin. The voltage across the BNO pin is proportional to the bulk capacitor voltage, referred as the line voltage. ...
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... MOSFET from being false-triggered by the coupling through the gate-to-drain capacitor C . Therefore, the MOSFET gate should be GD Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 pulled low to maintain in a off-state no matter the gate resistor is disconnected or opened in any case area ...
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... The LD7577JA has eliminated the parasitic SCR efficiently. Figure 25 shows the equivalent circuit of the LD7577JA’s Hi-V structure. It illustrates the LD7577JA is capable to sustain negative voltage and superior than similar products. Even though, a 40KΩ resistor is still recommended to be placed on the Hi-V path. ...
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... Reference Application Circuit --- 10W (5V/2A) Adapter Pin < 0.15W when Pout = 0W & Vin = 264Vac Schematic Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 16 www.leadtrend.com.tw LD7577JA ...
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... Package Information SOP-7 Symbols θ Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 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 ...
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... SOP-8 Symbols θ Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 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 0.254 ...
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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 LD7577JA-DS-00b November 2009 Dimension in Millimeters Dimensions in Inches Min Max 9 ...
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... Revision History Rev. Date Change Notice 00 5/4/2009 Original Specification 00a 7/27/2009 ESD Voltage Protection, Human Body Model (except HV Pin) Leading Edge Blanking Time update 00b 11/26/2009 1. Package option: SOP-7 2. Top mark information Leadtrend Technology Corporation LD7577JA-DS-00b November 2009 20 www.leadtrend.com.tw LD7577JA 2.5KV ...