MB3793-28A Power-Voltage Monitoring IC with Watchdog Timer Datasheet Description The MB3793 is an integrated circuit to monitor power voltage it incorporates a watchdog timer. A reset signal is output when the power is cut or falls abruptly. When the power recovers normally after resetting, a power-on reset signal is output to microprocessor units (MPUs). An internal watchdog timer with two inputs for system operation diagnosis can provide a fail-safe function for various application systems. Model No. Marking Code Detection voltage MB3793-28A 3793AR 2.8 V Features Precise detection of power voltage fall: 2.5% Detection voltage with hysteresis Low power dispersion: I = 41 A (Typ) CC Internal dual-input watchdog timer Watchdog timer halt function Independently-set watchdog and reset times Application Arcade Amusement etc. Cypress Semiconductor Corporation 198 Champion Court San Jose, CA 95134-1709 408-943-2600 Document Number: 002-08559 Rev. *C Revised June 22, 2017 MB3793-28A Contents Description ........................................................................1 8.4 Inhibition operation (Positive clock pulse) ........... 11 Features .............................................................................1 8.5 Clock pulse input supplementation Application ........................................................................1 (Positive clock pulse) ........................................................ 12 Contents ............................................................................2 9. Operation Sequence .........................................13 1. Pin Assignment ...................................................3 9.1 Positive clock pulse input .................................... 13 9.2 Negative clock pulse input ................................... 13 2. Pin Description ....................................................3 9.3 Single-clock input monitoring .............................. 13 3. Block Diagram .....................................................4 9.4 Description of Operations .................................... 13 4. Block Functions ..................................................5 10. Typical Characteristics ..................................15 4.1 Comp. S ................................................................5 11. Application Example .......................................18 4.2 Output circuit .........................................................5 11.1 Supply voltage monitor and watchdog timer ..... 18 4.3 Pulse generator .....................................................5 11.2 Supply voltage monitor and watchdog timer stop 19 4.4 Watchdog timer .....................................................5 11.3 Setting of compulsory reset .............................. 19 4.5 Logic circuit ...........................................................5 12. Usage Precaution ............................................20 5. Absolute Maximum Ratings ...............................6 13. Ordering Information ......................................20 6. Recommended Operating ConditionS ..............6 14. RoHS Compliance Information of Lead (Pb) 7. Electrical Characteristics ...................................7 Free version ...........................................................20 7.1 DC Characteristics ................................................7 7.2 AC Characteristics .................................................7 15. Package Dimensions ......................................21 8. Timing Diagram ...................................................8 16. Document History ...........................................22 8.1 Basic operation (Positive clock pulse) ..................8 Sales, Solutions, and Legal Information ......................23 8.2 Basic operation (Negative clock pulse) ................9 8.3 Single-clock input monitoring (Positive clock pulse) 10 Document Number: 002-08559 Rev. *C Page 2 of 23