MB91F376G Fujitsu Components, MB91F376G Datasheet - Page 179

• Manufacturer Part Number: MB91F376G
• Manufacturer: Fujitsu Components

Specifications of MB91F376G

• Lead Free Status / Rohs Status: Not Compliant

(2) 4 MHz real time clock configuration (SELCLK = 1)
(3) Use of real time clock module
When the SELCLK pad is connected logic level 1, the 32 kHz oscillation is disabled regardless of the software
setting. In this configuration, the Real Time Clock Module is supplied with the 4 MHz oscillation clock signal.
The following table summaries the modes available in this configuration.
There is some additional consideration needed to operate the RTC module to achieve the desired functionality.
Because the RTC module is directly connected to the 32 kHz oscillation clock, the oscillation stabilization time
has to be taken care of by the software.This can be achieved by using another timer (e.g the Time Base Timer)
to trigger the software to start the RTC module (Setting of ST bit to “1”) .
It is also important to stop the RTC module before entering the STOP mode. Otherwise, the reactivation from
STOP mode results in unpredictable operation of the RTC module.
After the reactivation, the oscillation stabilization time has to be measured again by the software, then the RTC
module can be restarted.
RTC4M
RTC4M
STOP
STOP
Mode
Mode
RUN
RUN
Power Dissipation
Medium Low
STOP
Lowest
0
1
1
High
Don’t Care
Don’t Care
PLL1EN
0 or 1
4 M Osc.
Stop
Run
Run
Don’t Care
Don’t Care
Don’t Care
PLL2EN
32 K Osc.
Software Setting
Stop
Stop
Stop
Operation of Components
Don’t Care
OSCD1
0
1
RTC
Stop
Run
Run
MB91360G Series
Don’t Care
Don’t Care
Don’t Care
Peripheral
OSCD2
CPU &
Stop
Stop
Run
Don’t Care
Don’t Care
Don’t Care
Stop/Run
RTC32
Stop
Stop
PLL
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