wm8400 Wolfson Microelectronics plc, wm8400 Datasheet - Page 145

• Manufacturer Part Number: wm8400
• Description: Wolfson Audioplustm Hi-fi Audio Codec And Power Management Unit For Mobile Multimedia
• Manufacturer: Wolfson Microelectronics plc

w
Pre-Production
HIBERNATE MODE CONFIGURATION
The DC-DC Converters and LDO Regulators are placed in Hibernate Mode when the WM8400 is in
Deep Sleep mode. The DC-DC Converters can also be individually placed in Hibernate Mode using
the DC1_SLEEP and DC2_SLEEP register bits.
The behaviour of the DC-DC Converters and LDO Regulators in Hibernate Mode may be set in
software. Each of the Converters and Regulators can be selected to switch off in Hibernate Mode, or
else to adopt a low power operating state and an ‘image’ voltage output. The applicable register
fields are described in Table 91.
When a DC-DC Converter is enabled in Hibernate mode, it operates as a low power LDO converter,
and not as a buck converter. Note that the DC-DC Converters and LDO Regulators must also be
enabled in hardware or software as described earlier.
Table 91 Hibernate Mode Configuration
R65 (41h)
R66 (42h)
R67 (43h)
R68 (44h)
R70 (46h)
R71 (47h)
R72 (48h)
R73 (49h)
REGISTER
ADDRESS
BIT
9:5
9:5
9:5
9:5
6:0
6:0
10
10
10
10
10
10
LDO1_HIB_M
ODE
LDO1_VIMG
[4:0]
LDO2_HIB_M
ODE
LDO2_VIMG
[4:0]
LDO3_HIB_M
ODE
LDO3_VIMG
[4:0]
LDO4_HIB_M
ODE
LDO4_VIMG
[4:0]
DC1_HIB_MO
DE
DC1_VIMG
[6:0]
DC2_HIB_MO
DE
DC2_VIMG
[6:0]
LABEL
1b
0000000b
DEFAULT
0000000b
00000b
00000b
00000b
00000b
0b
0b
0b
0b
1b
LDO1 Hibernate Mode
0 = LDO1 disabled in Hibernate
1 = LDO1 enabled in Hibernate
LDO1 Hibernate Mode output voltage
0.9v to 1.6v in 0.05v steps,
1.7 to 3.3v in 0.10v steps
See Table 87 for details.
LDO2 Hibernate Mode
0 = LDO2 disabled in Hibernate
1 = LDO2 enabled in Hibernate
LDO2 Hibernate Mode output voltage
0.9v to 1.6v in 0.05v steps,
1.7 to 3.3v in 0.10v steps
See Table 87 for details.
LDO3 Hibernate Mode
0 = LDO3 disabled in Hibernate
1 = LDO3 enabled in Hibernate
LDO3 Hibernate Mode output voltage
0.9v to 1.6v in 0.05v steps,
1.7 to 3.3v in 0.10v steps
See Table 87 for details.
LDO4 Hibernate Mode
0 = LDO4 disabled in Hibernate
1 = LDO4 enabled in Hibernate
LDO4 Hibernate Mode output voltage
0.9v to 1.6v in 0.05v steps,
1.7 to 3.3v in 0.10v steps
See Table 87 for details.
DC1 Hibernate Mode
0 = DC1 disabled in Hibernate
1 = DC1 enabled (LDO mode) in
Hibernate
DC1 Hibernate Mode output voltage
0.85v to 4.025v in 0.025v steps
See Table 88 for details
DC2 Hibernate Mode
0 = DC2 disabled in Hibernate
1 = DC2 enabled (LDO mode) in
Hibernate
DC2 Hibernate Mode output voltage
0.85v to 4.025v in 0.025v steps
See Table 88 for details
DESCRIPTION
PP, April 2009, Rev 3.0
WM8400
145