AS3685A/AS3685B

Datasheet

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AS3685

(ptr)

Revision 2.2

2 - 24

Table of Contents

1 General Description........................................................................................................................................... 1

2 Key Features ..................................................................................................................................................... 1

3 Applications ....................................................................................................................................................... 1

4 Application Diagram .......................................................................................................................................... 1

5 Characteristics................................................................................................................................................... 3

5.1 Absolute Maximum Ratings..................................................................................................................... 3

5.2 Operating Conditions .............................................................................................................................. 3

5.3 Electrical Characteristics ......................................................................................................................... 4

6 Typical Operation Characteristics...................................................................................................................... 6

7 Detailed Functional Description......................................................................................................................... 8

7.1 Low Noise Charge Pump ........................................................................................................................ 8

7.1.1 Mode Switching........................................................................................................................ 8

7.1.2 Soft Start .................................................................................................................................. 9

7.2 Current Source (Sink).............................................................................................................................. 9

7.2.1 AS3685A Current Setting......................................................................................................... 9

7.2.2 AS3685B Current Setting....................................................................................................... 12

7.2.3 AS3685A and AS3685B TXMask Function ............................................................................ 15

7.3 Protection Functions.............................................................................................................................. 16

7.3.1 Overtemperature Protection ................................................................................................... 16

7.3.2 Flash Timeout ........................................................................................................................ 16

7.4 Layout Recommendations..................................................................................................................... 16

8 External Components ...................................................................................................................................... 17

8.1 Capacitor and Resistor Selection .......................................................................................................... 17

8.2 Usage of PCB Wire Inductance............................................................................................................. 17

8.3 External Component Specifications ...................................................................................................... 17

9 Pinout and Packaging...................................................................................................................................... 18

9.1 DFN10 3x3mm ...................................................................................................................................... 18

9.1.1 Pin Assignments DFN10 3x3mm ........................................................................................... 18

9.1.2 Pin Descriptions DFN10 3x3mm ............................................................................................ 18

9.1.3 Package Drawings and Marking DFN10 3x3.......................................................................... 19

9.2 WL-CSP 2x1.5mm (Wafer Level Chip Scale Package) ......................................................................... 21

9.2.1 Pin Assignments WL-CSP 2x1.5mm...................................................................................... 21

9.2.2 Pin Descriptions WL-CSP 2x1.5mm....................................................................................... 21

9.2.3 Package Drawings and Marking WL-CSP 2x1.5mm .............................................................. 22

10 Ordering Information........................................................................................................................................ 23