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LD7552BPN (IC901):
The LD7552B are low cost, low startup current, current
mode PWM controllers with green-mode power- saving operation. The integrated functions
include the leading-edge blanking of the current sensing, internal slope
compensation. They provide the users a superior AC/DC power application of higher efficiency,
low external component counts, and lower cost solution. Furthermore, LD7552B feature more
protections like OLP (Over Load Protection) and OVP (Over Voltage Protection) to eliminate the
external protection circuits. It is designed for the switching adaptor with 30W~60W output,
offered in both SOP-8 and DIP-8 package.
The function of each pin and the inside circuit diagram are as follows
:
PIN Descriptions:
16
ViewSonic Corporation
Confidential - Do Not Copy
VA502mb-1
Summary of Contents for VA502mb-1
Page 10: ...7 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 13: ...10 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
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Page 16: ...PIN Descriptions 13 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 18: ...Block Diagram PIN Function 15 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 38: ...5 7 Packing Procedure 35 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 42: ...39 ViewSonic Corporation Confidential Do Not Copy VA502mb 1 6 Troubleshooting Flow Chart...
Page 43: ...7 Block Diagram 40 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 53: ...9 PCB Layout Diagrams MAIN BOARD 50 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 54: ...POWER BOARD 51 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 56: ...53 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 57: ...AUDIO BOARD 54 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 58: ...KEY BOARD 55 ViewSonic Corporation Confidential Do Not Copy VA502mb 1...
Page 61: ...58 ViewSonic Corporation Confidential Do Not Copy VA502mb 1 Packing for Shipping...