Rev. 1.10
40
November 04, 2019
Rev. 1.10
41
November 04, 2019
HT45F5Q-3
Battery Charger Flash MCU
HT45F5Q-3
Battery Charger Flash MCU
Operating Mode Switching
The device can switch between operating modes dynamically allowing the user to select the best
performance/power ratio for the present task in hand. In this way microcontroller operations that
do not require high performance can be executed using slower clocks thus requiring less operating
current and prolonging battery life in portable applications.
In simple terms, Mode Switching between the FAST Mode and SLOW Mode is executed using the
CKS2~CKS0 bits in the SCC register while Mode Switching from the FAST/SLOW Modes to the
SLEEP/IDLE Modes is executed via the HALT instruction. When a HALT instruction is executed,
whether the device enters the IDLE Mode or the SLEEP Mode is determined by the condition of the
FHIDEN and FSIDEN bits in the SCC register.
FAST
f
SYS
=f
H
~f
H
/64
f
H
on
CPU run
f
SYS
on
f
SUB
on
SLOW
f
SYS
=f
SUB
f
SUB
on
CPU run
f
SYS
on
f
H
on/off
IDLE0
HALT instruction executed
CPU stop
FHIDEN=0
FSIDEN=1
f
H
off
f
SUB
on
IDLE1
HALT instruction executed
CPU stop
FHIDEN=1
FSIDEN=1
f
H
on
f
SUB
on
IDLE2
HALT instruction executed
CPU stop
FHIDEN=1
FSIDEN=0
f
H
on
f
SUB
off
SLEEP
HALT instruction executed
CPU stop
FHIDEN=0
FSIDEN=0
f
H
off
f
SUB
off
