Table of Contents

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

2.0 Features ....................................................................................................................................................... 1

3.0 Block Diagram .............................................................................................................................................. 1

4.0 Pin Assignments ........................................................................................................................................... 2

5.0 Signal Descriptions ...................................................................................................................................... 4

6.0 Typical Application ........................................................................................................................................ 5

6.1 I/O EXPANSION OPTIONS ....................................................................................................................... 5

6.2 WATCHDOG TIMER ................................................................................................................................. 5

6.3 HALT MODE .............................................................................................................................................. 5

6.3.1 ACCESS.bus Activity ........................................................................................................................... 5

6.4 KEYPAD SCANNING ................................................................................................................................ 6

6.5 COMMUNICATION INTERFACE .............................................................................................................. 6

6.5.1 Interrupts Between the Host and LM8333 ..........................................................................................6

6.5.2 Interrupt Sources ................................................................................................................................. 6

7.0 Device Operation ......................................................................................................................................... 6

7.1 EVENT CODE ASSIGNMENT .................................................................................................................. 6

7.2 I/O EXPANSION ........................................................................................................................................ 7

7.2.1 PWM Output with Programmable Duty Cycle ..................................................................................... 7

7.2.2 General-Purpose I/O (GPIO) ............................................................................................................... 8

7.2.3 External Interrupts ............................................................................................................................... 9

7.3 HOST COMMAND EXECUTION ............................................................................................................ 10

7.3.1 Command Structure ........................................................................................................................... 10

7.4 HOST WRITE COMMANDS ................................................................................................................... 10

7.5 HOST READ COMMANDS ..................................................................................................................... 10

7.6 WAKE-UP FROM HALT MODE .............................................................................................................. 11

8.0 Interrupts .................................................................................................................................................... 12

8.1 INTERRUPT CODE ................................................................................................................................. 12

8.2 ERROR CODE ........................................................................................................................................ 12

8.3 STATUS CODES ..................................................................................................................................... 12

8.4 INTERRUPT PROCESSING ................................................................................................................... 12

8.5 COMMAND EXECUTION SUMMARY .................................................................................................... 13

9.0 Electrical Characteristics ............................................................................................................................ 14

10.0 Absolute Maximum Ratings ..................................................................................................................... 14

11.0 DC Electrical Characteristics .................................................................................................................... 14

12.0 AC Electrical Characteristics .................................................................................................................... 15

13.0 Physical Dimensions ................................................................................................................................ 17

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