CS43130 Datasheet, PDF (34/137 Pages) Cirrus Logic – 130-dB, 32-Bit High-Performance DAC with Integrated Headphone Driver

CS43130
4.5 Headphone Presence Detect and Output Load Detection
the sense pin is shorted to the output signal and, therefore, is pulled below a certain threshold via the output stage of the
HP amp. Thus, a low level at the sense pin indicates plug inserted, and a high level at the sense pin indicates plug
removed.
4.5.1.3 Headphone Detect Registers
This section describes the behavior and interaction of the headphone-detect debounce register fields. See Fig. 4-10 for
reference.
HP Detect Block
HPDETECT_CTRL p. 112
HP Detect
Debounced Status
HPDETECT_PLUG_DBC p. 112
HPDETECT_UNPLUG_DBC
p. 113
HP_DETECT
HPDETECT_RISE_DBC_TIME p. 112
No
Delay
0
RISE DEBOUNCE
1
FALL_DEBOUNCE
HPDETECT_INV
p. 112
No
Delay
HPDETECT_FALL_DBC_TIME p. 112
HP Detect
Plug/Unplug
Detect
Interrupt Handler Block
HP Detect
Plug/Unplug Interrupt
Mask
HPDETECT_PLUG_INT_
INT
MASK p. 117
HPDETECT_UNPLUG_
INT_MASK p. 118
HP Detect
Plug/Unplug Interrupt
Status
HPDETECT_PLUG_INT
p. 115
HPDETECT_UNPLUG_
INT p. 115
Read
Deasserts INT
Figure 4-10. Headphone Detect Block Diagram
• HPDETECT_CTRL configures the operation of the HP detect circuit.
• HPDETECT_INV inverts the signal from the HP detect circuit.
• HPDETECT_FALL_DBC_TIME configures the HP_DETECT falling debounce time.
• HPDETECT_RISE_DBC_TIME configures the HP_DETECT rising debounce time.
• HPDETECT_PLUG_DBC shows the falling-edge-debounced version of HP_DETECT signal.
• HPDETECT_UNPLUG_DBC shows the rising-edge-debounced version of HP_DETECT signal.
• HPDETECT_PLUG_INT shows the headphone plug-in event status.
• HPDETECT_UNPLUG_INT shows the headphone unplug event status.
• HPDETECT_PLUG_INT_MASK is the interrupt mask of headphone plug-in event status.
• HPDETECT_UNPLUG_INT_MASK is the interrupt mask of headphone unplug event status.
4.5.1.4 Headphone Detect and Interrupts Setup Instructions
The following steps are required for activation of headphone-detect debounce interrupt status:
1. Ensure the I²C is ready to respond to control port command.
2. Clear the interrupt masks.
3. Write to HPDETECT_RISE_DBC_TIME and HPDETECT_FALL_DBC_TIME (see p. 112) to enable debounce for
presence detect plug/unplug.
4. Set HPDETECT_CTRL to 11 to enable the HPDETECT functions.
The interrupt status bits can be found in Section 7.6.1. The status does not contain an event-capture latch (a read always
yields the current condition).
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