ld7576jps Leadtrend Technology, ld7576jps Datasheet
ld7576jps
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ld7576jps Summary of contents
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... OLP (Over Load Protection), OVP (Over Voltage Protection) and OTP (Over Temperature Protection) to prevent the circuit damage under abnormal conditions. The LD7576X series are available in DIP-8 and SOP-8 package. Typical Application Leadtrend Technology Corporation LD7576-DS-03 December 2007 LD7576/76H/76J/76K Features High-Voltage (500V) Startup Circuit Current Mode Control ...
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... LD7576/76H/76J/76K Top Mark Shipping LD7576PS 2500 /tape & reel LD7576GS 2500 /tape & reel LD7576PN 3600 /tube /Carton LD7576JPS 2500 /tape & reel 2500 /tape & reel LD7576JPN 3600 /tube /Carton LD7576HPS 2500 /tape & reel 2500 /tape & reel LD7576HPN ...
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... Connect this pin to positive terminal of bulk capacitor to provide the startup current 8 HV for the controller. When Vcc voltage trips the UVLO(on), this HV loop will be off to save the power loss on the startup circuit. Leadtrend Technology Corporation LD7576-DS-03 December 2007 FUNCTION 3 www.leadtrend.com.tw LD7576/76H/76J/76K ...
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... Block Diagram Leadtrend Technology Corporation LD7576-DS-03 December 2007 ∑ 4 www.leadtrend.com.tw LD7576/76H/76J/76K ...
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... Recommended Operating Conditions Item Supply Voltage Capacitor CC CT Value COMP Pin Capacitor Leadtrend Technology Corporation LD7576-DS-03 December 2007 Min. Max 0.047 0.1 1 ...
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... Current Sensing (CS Pin) Maximum Input Voltage Leading Edge Blanking Time Input impedance Delay to Output Oscillator for Switching Frequency Frequency Green Mode Frequency Trembling Frequency Temp. Stability Voltage Stability Leadtrend Technology Corporation LD7576-DS-03 December 2007 =15.0V) CC CONDITIONS Vcc< UVLO(on),HV=500V Vcc> UVLO(off),HV=500V V =0V COMP V ...
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... OLP Trip Level OLP Delay Time OTP (Over Temperature) OTP Level OTP Hysteresis Latch Protection CT Pin Trip Level for Latch Protection Timer for Power-on Verification De-Latch Vcc Level Leadtrend Technology Corporation LD7576-DS-03 December 2007 =15.0V) CC CONDITIONS CT=0.047μF (-40°C ~105°C) (VCC=11V-25V) VCC=15V, Io=20mA ...
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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 -40 40 Temperature (°C) Fig. 5 Frequency vs. Temperature Leadtrend Technology Corporation LD7576-DS-03 December 2007 0.88 0.86 0.84 0.82 0.80 0.78 120 125 80 -40 12 11.2 10.4 9.6 8 120 125 - ...
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... Vcc (V) 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 LD7576-DS-03 December 2007 120 125 -40 6.0 5.5 5.0 4.5 4 ...
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... Vcc capacitor C1. During the startup transient, the Vcc drops lower than the UVLO threshold so the current source Leadtrend Technology Corporation LD7576-DS-03 December 2007 will be enabled to supply 1mA current. Meanwhile, the Vcc supply current is as low as 100μA that most of the HV current is adopted to charge the Vcc capacitor ...
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... UC384X, is with 2 diodes voltage offset to feed the voltage divider with 1/3 ratio, that is × PWM COMPARATOR 3 A pull-high resistor is embedded internally to optimize the external circuit. Generally, an external capacitor in parallel to photo-coupler is required in application. Leadtrend Technology Corporation LD7576-DS-03 December 2007 maximum voltage − COMP ...
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... The OLP delay time, set by CT pin prevent the false triggering from the power-on and turn-off transient. Higher CT value will Leadtrend Technology Corporation LD7576-DS-03 December 2007 generate longer OLP delay time. The recommended CT value will be 0.1μF when OLP delay time is for around 110mS and 0.047μ ...
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... PDR (8V) Latch Released AC input Voltage AC Off OUT Switching Non- Switching Fig. 18 Leadtrend Technology Corporation LD7576-DS-03 December 2007 OVP (Over Voltage Protection) on Vcc - Auto Recovery The maximum V mostly for 30V. To prevent the V LD7576X series are implemented with OVP function on Vcc. t Whenever the Vcc voltage is higher than the OVP threshold, ...
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... R8 can provide a discharge path to avoid the MOSFET from being false-triggered by the current through the gate-to-drain capacitor C . Therefore, the MOSFET GD is always pulled low and placed in the off-state whenever the gate resistor is disconnected or opened in any case. Leadtrend Technology Corporation LD7576-DS-03 December 2007 14 www.leadtrend.com.tw LD7576/76H/76J/76K Fig ⋅ ...
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... An internal OTP circuit is embedded inside the LD7576/76J to provide the worst-case protection for this controller. When the chip temperature rises higher than the trip OTP level, the Leadtrend Technology Corporation LD7576-DS-03 December 2007 output will be disabled until the chip is cooled down below the hysteresis window. On-Chip OTP – ...
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... Reference Application Circuit --- 10W (5V/2A) Adapter Leadtrend Technology Corporation LD7576-DS-03 December 2007 16 www.leadtrend.com.tw LD7576/76H/76J/76K ...
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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 LD7576-DS-03 December 2007 Original P C51 C52 C54 C55 CT CX1 CY1 D1A D1B D1C D1D ...
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... Package Information SOP-8 Symbols θ Leadtrend Technology Corporation LD7576-DS-03 December 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 5.791 6 ...
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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 LD7576-DS-03 December 2007 Dimension in Millimeters Dimensions in Inches ...
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... Original Specification. 01 4/23/07 Oscillator for Switching Frequency updated 02 6/21/07 Electrical Characteristics updated 03 11/30/2007 1. Features: Adjustable OLP delay time 2. Detailed Description for COMP pin capacitor. 3. Electrical Characteristics/ Low Frequency Timer 4. Green package option. 5. Block Diagram revision. Leadtrend Technology Corporation LD7576-DS-03 December 2007 20 www.leadtrend.com.tw LD7576/76H/76J/76K ...