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Mini57
Apr. 06, 2017
Page 121 of 475
Rev.1.00
MINI5
7
S
E
RI
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TECH
NIC
A
L R
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F
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RE
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CE
MA
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UA
L
6.3.8
Register Description
Power-down Control Register (CLK_PWRCTL)
Except the BIT[6], all the other bits are protected, and programming these bits need to write 0x59,
0x16, 0x88 to address 0x5000_0100 to disable register protection. Refer to the SYS_REGLCTL
register at address 0x100.
Register
Offset
R/W
Description
Reset Value
CLK_PWRCT
L
0x00
R/W
System Power-down Control Register
0x0000_001C
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
15
14
13
12
11
10
9
8
Reserved
HXTGAIN
PDLXT
Reserved
7
6
5
4
3
2
1
0
PDEN
PDWKIF
PDWKIEN
PDWKDLY
LIRCEN
HIRCEN
XTLEN
Bits
Description
[31:12]
Reserved
Reserved.
[11:10]
HXTGAIN
HXT Gain Control (Write Protect)
This is a protected register. Please refer to open lock sequence to program it.
Gain control is used to enlarge the gain of crystal to make sure crystal work normally. If
gain control is enabled, crystal will consume more power than gain control off.
00 = HXT frequency is lower than from 8 MHz.
01 = HXT frequency is from 8 MHz to 12 MHz.
10 = HXT frequency is from 12 MHz to 16 MHz.
11 = HXT frequency is higher than 16 MHz.
Note:
This bit is write protected. Refer to the SYS_REGLCTL register.
[9]
PDLXT
LXT Alive in Power-down
0 = LXT will be turned off automatically when chip enters Power-down.
1 = If XTLEN[1:0] are 0x2, LXT keeps active in Power-down.
[8]
Reserved
Reserved.
[7]
PDEN
System Power-down Enable Bit (Write Protect)
When this bit is set to 1, Power-down mode is enabled.
When chip wakes up from Power-down mode, this bit is auto cleared. Users need to set
this bit again for next Power-down.
In Power-down mode, HXT and the HIRC will be disabled in this mode, but LXT and LIRC
are not controlled by Power-down mode.
In Power-down mode, the system clocks are disabled, and ignored the clock source
selection. The clocks of peripheral are not controlled by Power-down mode, if the