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Maxim > Design Support > Technical Documents > Application Notes > Automotive > APP 655
Maxim > Design Support > Technical Documents > Application Notes > Microprocessor Supervisor Circuits > APP 655
Keywords: microprocessor supervisor, battery backup, false reset, power on reset, power good circuit, reset circuit, early warning, sleep
mode, uP supervisor, microprocessor, supervisory, supervisor ICs
APPLICATION NOTE 655
Supervisor ICs Monitor Battery-Powered Equipment
Mar 13, 2000
To ensure correct operation, most microprocessor-based systems require supervision during power-up and power-down, and when
entering or exiting shutdown or sleep mode. The supervisor may only provide a power-on reset, or it may offer additional functions,
such as backup-battery management, memory-write protection, low-line early warning, or a software watchdog (Figure 1).
Figure 1. A feature-laden µP supervisor (IC1), with the help of the µP itself, performs a variety of functions in this typical application
circuit.
You can get these functions all together or in various combinations, by selecting one of the many available microprocessor (µP)
supervisor ICs (also called power-on resets, power-good circuits, reset circuits, etc.). The following discussion helps you choose the one
best suited to your application, and offers solutions for many common µP supervisory problems.
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