WM8310GEB/V Wolfson Microelectronics, WM8310GEB/V Datasheet - Page 109

• Manufacturer Part Number: WM8310GEB/V
• Description: POWER MANAGEMENT SUBSYSTEM, 169BGA
• Manufacturer: Wolfson Microelectronics

Specifications of WM8310GEB/V

• Supply Voltage: 7V
• No. Of Step-down Dc - Dc Converters: 4
• No. Of Ldo Regulators: 11
• Digital Ic Case Style: BGA
• No. Of Pins: 169
• No. Of Regulated Outputs: 13
• Operating Temperature Range: -40°C To
• Rohs Compliant: Yes
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Pre-Production
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it is providing power to the system. The charger resumes operation automatically as soon as
sufficient current capacity is available from the main power source.
After the battery has been fully charged and the charge process has terminated, battery charging will
automatically re-start if the battery voltage falls below the charger re-start threshold.
Figure 26 A Typical Charge Cycle
17.7.2
The battery charger may be enabled when the WM8310 is in the ON or SLEEP power states. Note
that battery charging is only possible when the selected power source is within normal operating
limits.
The battery charger is enabled when the CHG_ENA register bit is set to 1. When enabled, it checks
if the conditions for charging are fulfilled and it controls the charging processes accordingly. The
status of the battery charger can be read from the CHG_ACTIVE register bit.
The target voltage for the battery is set by the CHG_VSEL field, as defined in Table 58. It is
important that this field is correctly set according to the type of battery that is connected. Incorrect
setting of this register may lead to a safety hazard condition.
The trickle charge current is selected using the CHG_TRKL_ILIM field. This is the maximum trickle
charge current - the actual charge current will be reduced if the battery is fully charged, or if the
system supply, SYSVDD, drops as described in Section 17.7.1.
When the battery reaches the target voltage, the charger enters the constant voltage charge phase,
in which the WM8310 regulates BATTVDD to the target voltage. When the charger is in the constant
voltage charge phase, then the CHG_TOPOFF bit will be set to indicate that the charge is
approaching completion.
The WM8310 incorporates thermal sensors to detect excessive temperatures within the device and
to provide self-protection (see Section 26). By default, the battery charger will be disabled if the
Thermal Warning condition occurs, and will be re-enabled after the condition has cleared. This
response can be disabled by setting CHG_CHIP_TEMP_MON = 0, allowing the battery charge to
continue. The Thermal Warning threshold is the lower of the two device temperature thresholds; the
Thermal Shutdown threshold is the higher threshold. Note that the Thermal Shutdown condition
cannot be ignored; this event causes a System Reset and a termination of battery charging.
If the WM8310 is commanded to the OFF state for any reason, then battery charging will be
terminated. The CHG_OFF_MASK bit can be used to prevent certain OFF transitions whilst the
battery charger is active. Setting the CHG_OFF_MASK bit causes a ‘Software OFF request’, ‘ON pin
request’ or GPIO OFF request to be ignored whilst the charger is active. See Section 11.3 for a full
list of OFF transition events.
The register control fields for trickle charging are described in Table 58. See Section 17.7.4 for
details of battery charge termination.
Note that the Battery Charger control registers are locked by the WM8310 User Key. These registers
can only be changed by writing the appropriate code to the Security register, as described in
Section 12.4.
BATTERY CHARGER ENABLE
PP, December 2009, Rev 3.0
WM8310
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