wm8400 Wolfson Microelectronics plc, wm8400 Datasheet - Page 150

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

WM8400
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INTERRUPT EVENTS
The WM8400 continuously monitors its input and output voltages, device temperature and other
events. The NIRQ output pin can be used to signal events or abnormal conditions associated with
these monitoring functions. Register fields also provide the ability to read the status of these event
detection features. The debounced status of these fields is available in Register 81 (51h).
By default, each of these fields will trigger an Interrupt (IRQ) event, resulting in the corresponding bit
in Register 79 (4Fh) being set. Individual Mask bits in Register 80 (50h) can be used to prevent an
Interrupt being generated by a specific event.
In the case of MIC Current detect, MIC Short Circuit detect, Jack detect (Left) and Jack detect
(Right), an Interrupt event is triggered on rising and falling edges of the event. All other Interrupt
events occur only on the rising edge of the event (eg. when a temperature threshold is exceeded, or
an LDO goes undervoltage).
The unmasked Interrupt events are latched in Register 79 (4Fh) until a Register Read is scheduled at
that address. When any Interrupt event is latched in Register 79 (4Fh), the NIRQ pin is set logic low
(referenced to the MBVDD power domain). The NIRQ will return to its normal logic high level after the
Interrupt Status Register (R79) has been read.
The Register fields associated with the Interrupt events are described in Table 99.
R79 (4Fh)
REGISTER
ADDRESS
BIT
15
14
13
12
11
10
9
8
7
6
5
MICD_CINT
MICSCD_CINT
JDL_CINT
JDR_CINT
CODEC_SEQ_END
_EINT
CDEL_TO_EINT
CHIP_GT150_EINT
CHIP_GT115_EINT
LINE_CMP_EINT
UVLO_EINT
DC2_UV_EINT
LABEL
DEFAULT
0b
0b
0b
0b
0b
0b
0b
0b
0b
0b
0b
MIC Current Detect IRQ status
0 = MIC Current IRQ not set
1 = MIC Current IRQ set
MIC Short Circuit IRQ status
0 = MIC Short Circuit IRQ not set
1 = MIC Short Circuit IRQ set
Jack Detect (Left) IRQ status
0 = Jack Detect (Left) IRQ not set
1 = Jack Detect (Left) IRQ set
Jack Detect (Right) IRQ status
0 = Jack Detect (Right) IRQ not set
1 = Jack Detect (Right) IRQ set
CODEC softstart or shutdown status
0 = CODEC sequence normal
1 = CODEC softstart or shutdown
sequence completed
CDELAY IRQ status
0 = CDELAY normal
1 = Reset Delay Timer was triggered
by 500ms timeout OR invalid CDELAY
capacitance caused CDELAY error.
Temperature Level 2 IRQ status
0 = 150°C threshold not exceeded
1 = 150°C threshold exceeded
Temperature Level 1 IRQ status
0 = 115°C threshold not exceeded
1 = 115°C threshold exceeded
Battery Comparator IRQ status
0 = Battery Comparator normal
1 = Battery Comparator undervoltage
UVLO IRQ status
0 = UVLO disabled
1 = UVLO enabled
DC2 Converter IRQ status
0 = DC2 voltage normal
1 = DC2 undervoltage detected
DESCRIPTION
PP, April 2009, Rev 3.0
Pre-Production
150