General Description
The LD7551C is built-in with several functions, protections and an EMI-improved solution in a SOT-26 package. It takes less components counts or circuit space, especially ideal for those cost sensitive applications.
The LD7551C integrates low startup current, green-mode power-saving operation, leading-edge blanking of the current sensing and internal slope compensation. It also features protections like OLP (Over Load Protection) and OVP (Over Voltage Protection) to prevent the circuit damage under the abnormal conditions.
Furthermore, the frequency trembling function is to reduce the noise level and help the power circuit designers for the EMI filter design with minimum component cost and developing time.
Features
• Very Low Startup Current (<20μA)
• Current Mode Control
• Non-audible-noise Green Mode Control
• UVLO (Under Voltage Lockout)
• LEB (Leading-Edge Blanking) on CS Pin
• Programmable Switching Frequency
• Internal Trembling (4KHz)
• Internal Slope Compensation
• OVP (Over Voltage Protection) on Vcc Pin
• OLP (Over Load Protection)
• 500mA Driving Capability
Applications
• Switching AC/DC Adaptor and Battery Charger
• Open Frame Switching Power Supply
Typical Application
Typical Application
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