WM8310 Datasheet, PDF (108/291 Pages) Wolfson Microelectronics plc – Processor Power Management Subsystem

WM8310
Pre-Production
ADDRESS BIT
LABEL
DEFAULT
R16387
5:4 USB100MA_START
00
(4003h)
UP [1:0
Power
State
3 USB_CURR_STS
0
2:0 USB_ILIM
010
Table 55 Configuring the USB Power Operation
DESCRIPTION
Sets the device behaviour when starting
up under USB power, when USB_ILIM
= 010 (100mA)
00 = Normal
01 = Soft-Start
10 = Only start if BATTVDD > 3.1V
11 = Only start if BATTVDD > 3.4V
In the 1X modes, if the battery voltage
is less than the selected threshold, then
the device will enable trickle charge
mode instead of executing the start-up
request. The start-up request is delayed
until the battery voltage threshold has
been met. Note that trickle charge is
only possible when CHG_ENA=1.
Indicates if the USB current limit has
been reached
0 = Normal
1 = USB current limit
Sets the USB current limit
000 = 0mA (USB switch is open)
001 = 2.5mA
010 = 100mA
011 = 500mA
100 = 900mA
101 = 1500mA
110 = 1800mA
111 = 550mA
Note that, when starting up the
WM8310 with the USBVDD supply
selected, the USB_ILIM register must
be set to 100mA or higher.
17.5 POWER PATH MANAGEMENT INTERRUPTS
The Power Path Management circuit is associated with three Interrupt event flags.
The PPM_SYSLO_EINT interrupt bit is set when the internal signal SYSLO is asserted. This indicates
a SYSVDD undervoltage condition, described in Section 24.4.
The PPM_PWR_SRC_EINT interrupt bit is set whenever the status of the Wall or USB supplies
changes, indicating a connection, disconnection, or a voltage. See Section 17.1.
The PPM_USB_CURR_EINT interrupt bit is set whenever the permitted USB current limit has been
reached. See Section 17.4.
Each of these secondary interrupts triggers a primary Power Path Management Interrupt, PPM_INT
(see Section 23). This can be masked by setting the mask bit(s) as described in Table 56.
w
PP, May 2012, Rev 3.1
108