dpa422 Power Integrations, Inc., dpa422 Datasheet - Page 2

• Manufacturer Part Number: dpa422
• Description: Highly Integrated Dc-dc Converter Ics For Power Over Ethernet & Telecom Applications
• Manufacturer: Power Integrations, Inc.

Rev. S 12/07
Functional Block Diagram ....................................................................................................................................... 3
Pin Functional Description ...................................................................................................................................... 3
DPA-Switch Family Functional Description ............................................................................................................ 4
Using Feature Pins ..................................................................................................................................................... 8
Typical Uses of FREQUENCY (F) Pin ...................................................................................................................... 11
Typical Uses of LINE-SENSE (L) and EXTERNAL CURRENT LIMIT (X) Pins ....................................................... 11
Application Examples .............................................................................................................................................. 14
Key Application Considerations .............................................................................................................................. 16
Product Specifi cations and Test Conditions .......................................................................................................... 21
Typical Performance Characteristics .................................................................................................................. 27
Part Ordering Information ....................................................................................................................................... 30
Package Outlines .................................................................................................................................................... 31
2
CONTROL (C) Pin Operation .................................................................................................................................... 4
Oscillator and Switching Frequency .......................................................................................................................... 5
Pulse Width Modulator & Maximum Duty Cycle ........................................................................................................ 5
Minimum Duty Cycle and Cycle Skipping ................................................................................................................. 6
Error Amplifi er .......................................................................................................................................................... 6
On-chip Current Limit with External Programmability ................................................................................................ 6
Line Under-Voltage Detection (UV) ............................................................................................................................ 6
Line Overvoltage Shutdown (OV) .............................................................................................................................. 6
Line Feed-Forward with DC
Remote ON/OFF ...................................................................................................................................................... 7
Synchronization ........................................................................................................................................................ 7
Soft-Start ................................................................................................................................................................. 8
Shutdown/Auto-Restart ........................................................................................................................................... 8
Hysteretic Over-Temperature Protection ................................................................................................................... 8
Bandgap Reference ................................................................................................................................................. 8
High-Voltage Bias Current Source ............................................................................................................................ 8
FREQUENCY (F) Pin Operation ................................................................................................................................ 8
LINE-SENSE (L) Pin Operation ................................................................................................................................. 9
EXTERNAL CURRENT LIMIT (X) Pin Operation ......................................................................................................... 9
DPA-Switch Design Considerations ........................................................................................................................ 16
DPA-Switch Layout Considerations ........................................................................................................................ 18
Quick Design Checklist .......................................................................................................................................... 19
Design Tools .......................................................................................................................................................... 20
DPA422-426
MAX
Reduction ................................................................................................................ 6
Section List
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