Rohm LAPIS SEMICONDUCTOR ML620Q503, User Manual

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ML620Q503/Q504 User's Manual
Chapter 28 Voltage Level Supervisor
FEUL620Q504 28-4
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ENVLS (bit 8)
The ENVLS bit is used to control ON/OFF of the VLS.
VLS is turned on when ENVLS is set to "1", and off when “0”.
When the VLS reset is issued, the VLS keep the ON state.
ENVLS Description
0 VLS: OFF (initial value)
1 VLS : ON
[Note]
Set VLSLV3 to VLSLV0 bits to any one of between”3”~”B”h, before setting ENVLS bit to “1”.
Operation is not guaranteed in the case of the other setting.
•
VLSF (bit 9)
VLSF is the voltage level detection flag.
It is “0” when the power supply voltage (V
DD
) is higher than the threshold voltage (V
VLS
), or “1” when
the power supply voltage is lower than the threshold voltage. VLSF is initialized to 0 when VLS is set to
on (ENVLS=1).
VLSF Description
0 Higher than the threshold voltage (initial value)
1 Lower than the threshold voltage
•
VLSRF (bit 10)
The VLSRF flag is used to indicate whether the voltage level detection result is valid.
When the threshold voltage value becomes valid (readable from CPU), this becomes ”1”.
VLSRF Description
0 VLS is OFF or VLS is being judged (initial value)
1 VLS judgment result is valid
[Note]
Make sure that the VLSRF bit is set to ”1” before enabling the STOP mode.