Rohm LAPIS SEMICONDUCTOR ML620Q503, User Manual

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ML620Q503/Q504 User's Manual
Chapter 28 Voltage Level Supervisor
FEUL620Q504 28-7
28.3 Description of Operation
The VLS can judge whether V
DD
on the CPU is lower or higher than the specified threshold voltage by reading
SFR, and also it can issue a VLS interrupt or VLS reset when V
DD
becomes lower than the specified threshold
voltage.
The VLS has a hysteresis charactristics(H
VLS
), The threshold voltage of rise is V
VLS
+ H
VLS
. For detail, see VLS
characteristic in Appendix C.
The following operation mode are provided:
Supervisor mode:
Set ENVLS to ”1” to turn on VLS for voltage judgment. When the judgment result becomes valid,
it is notified by using the VLSRF flag. The judgment still continues.
VLS interrupt or VLS reset can be set to constantly monitor the power supply voltage and issue an
interrupt or reset when it becomes lower than the threshold voltage.