WM8310GEB/V Wolfson Microelectronics, WM8310GEB/V Datasheet - Page 70

• 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

WM8310
15.7 DC-DC BOOST CONVERTER CONTROL
15.8 LDO REGULATOR CONTROL
15.9 HARDWARE CONTROL (GPIO)
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The WM8310 can indicate the status of the Dynamic Voltage Scaling via a GPIO pin configured as a
“DC-DC1 DVS Done” or “DC-DC2 DVS Done” output (see Section 21). When a GPIO pin is
configured to indicate the DVS status, this signal is temporarily de-asserted during a DVS transition
on the associated DC-DC Converter, and is subsequently asserted to indicate the transition has
completed.
Note that the GPIO DVS outputs indicate the progress of all output voltage slews; they are not limited
to transitions associated with DCm_DVS_SRC; the GPIO DVS output also indicates the status of a
slew caused by a write to the DCm_ON_VSEL register, or a slew to the DCm_SLP_VSEL voltage.
Note also that the GPIO DVS outputs are indicators of the DVS control mechanism only; they do not
confirm the output voltage accuracy. The output voltage can be checked using the voltage status bits
if required (see Section 15.2).
The DC-DC4 Boost Converter is designed as a power source for the Current Sinks described in
Section 16. The associated control registers for DC-DC4 are described in Section 15.4.2.
The Boost Converter uses one or other of the Current Sinks to provide voltage feedback in order to
control the converter output voltage. The selected Current Sink is determined by the DC4_FBSRC
register bit. If the Boost Converter is used to provide a supply for both ISINKs simultaneously, then
the DC4_RANGE and DC4_FBSRC bits should be set according to whichever of the ISINKs requires
the higher supply voltage.
It is important to follow the recommended control sequences for switching on/off the Boost Converter
and Current Sinks. These sequences are described in Section 16.
The maximum current that can be supported by the Boost Converter varies with the output voltage,
as noted in the Electrical Characteristics (see Section 7.2).
The Current Sinks are suited to controlling LED backlight circuits. At low output voltages (eg. 5V), the
DC-DC4 boost converter is capable of supporting currents which exceed the maximum current rating
of the Current Sinks. Please contact Wolfson Applications support if further guidance is required on
configuring DC-DC4 for higher current than is supported by the Current Sinks.
The LDO Regulators 1-10 can be configured to act as Current Limited Switches by setting the
LDOn_SWI field. When this bit is selected, there is no voltage regulation and the operating mode
and output voltage controls of the corresponding LDO are ignored. In Switch mode, the switch is
enabled (closed) and disabled (opened) by enabling or disabling the LDO.
Note that Switch mode cannot be selected via the OTP memory settings, and must be configured
after the WM8310 has entered the ON state.
When the LDO Regulator is disabled (and Switch mode is not selected), the output pin can be
configured to be floating or to be actively discharged. This is selected using LDOn_FLT.
The DC-DC Converters, LDO Regulators and EPE outputs may be controlled by the Hardware
Control inputs supported via the GPIO pins. The DCm_HWC_SRC, LDOn_HWC_SRC or
EPEn_HWC_SRC fields determine which of these Hardware Control inputs is effective.
See Section 21 for details of configuring the GPIO pins as Hardware Control inputs. Note that the
GPIO Hardware Control function is not the same as the GPIO Hardware Enable function.
Hardware Control is only possible when the applicable DCm_ENA, LDOn_ENA or EPEn_ENA control
bit is set (see Section 15.2), or if a Hardware Enable has been assigned to the relevant function and
is asserted.
The action taken in response to the selected Hardware Control inputs is configurable for each DC-DC
Converter, LDO Regulator or EPE output. The available options are described below.
PP, December 2009, Rev 3.0
Pre-Production
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