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AX5031

2

Table of Contents

1. Overview.......................................................................................................................................4

1.1. Features .............................................................................................................................................. 4

1.2. Applications....................................................................................................................................... 4

2. Block Diagram..............................................................................................................................5

3. Pin Function Descriptions ............................................................................................................6

3.1. Pin List.................................................................................................................................................. 6

3.2. Pinout Drawing.................................................................................................................................. 7

4. Specifications ...............................................................................................................................8

4.1. Absolute Maximum Ratings ............................................................................................................ 8

4.2. DC Characteristics ........................................................................................................................... 9

Supplies ............................................................................................................................................... 9

Logic .................................................................................................................................................. 11

4.3. AC Characteristics ......................................................................................................................... 12

Crystal Oscillator.............................................................................................................................. 12

RF Frequency Generation Subsystem (Synthesizer).................................................................. 13

Transmitter ........................................................................................................................................ 14

SPI Timing .......................................................................................................................................... 15

5. Circuit Description......................................................................................................................16

5.1. Voltage Regulator.......................................................................................................................... 17

5.2. Crystal Oscillator ............................................................................................................................. 17

5.3. SYSCLK Output ................................................................................................................................ 18

5.4. Power-on-reset (POR) .................................................................................................................... 18

5.5. RF Frequency Generation Subsystem......................................................................................... 18

VCO ................................................................................................................................................... 19

VCO Auto-Ranging ........................................................................................................................ 19

Loop Filter and Charge Pump ...................................................................................................... 19