wm8351 Wolfson Microelectronics plc, wm8351 Datasheet - Page 131

• Manufacturer Part Number: wm8351
• Description: Wolfson Audioplus? Stereo Codec With Power Management
• Manufacturer: Wolfson Microelectronics plc

Production Data
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The DC2_ILIM bits defined in Table 76 should be set according to the intended output load
conditions.
R183 (B7h)
DC-DC2 Control
Table 76 Operating Mode Control for DC-DC Converter 2
DC-DC Converter 2 can also be controlled by the device HIBERNATE bit, or by hardware input
signals L_PWR1, L_PWR2 and L_PWR3. Several GPIO pins can be assigned as L_PWR pins. The
converter can be assigned to one of these three signals, or else to the device HIBERNATE bit. The
signals are active high and the converter’s response to the selected signal is programmable as
defined in Table 77.
Note that, when a GPIO pin is configured as a Hibernate input pin, and this input is asserted, then all
DC-DC Converters will be placed in Hibernate mode.
In order to use GPIO pins as L_PWR pins, they must be configured by setting the respective
GPn_FN, and GPn_DIR bits to the appropriate value (see Section 20).
ADDRESS
BIT
4:3
1:0
14
6
DC2_MODE
DC2_ILIM
DC2_RMPH
DC2_RMPL
DC2_FBSRC
[1:0]
LABEL
DEFAULT
01
00
0
0
DC-DC2 Converter Mode
0 = boost mode
1 = switch mode
DC-DC2 peak current limit select
0 = Higher peak current
1 = Lower peak current
DC-DC2 compensation ramp
{DC2_RMPH, DC2_RMPL}
00 = 20V < VOUT ≤ 30V
01 = 10V < VOUT ≤ 20V
10 = 5V < VOUT ≤ 10V
11 = VOUT ≤ 5V (will be chosen
automatically if DC2_FBSRC=11)
DC-DCn voltage feedback selection
00 = voltage feedback (using external
resistor divider on pin FBn)
01 = current sink ISINKA used as
feedback
10 = Reserved
11 = voltage feedback (using internal
resistor divider on pin USB)
DESCRIPTION
PD, June 2009, Rev 4.1
WM8351
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