cs43l43 Cirrus Logic, Inc., cs43l43 Datasheet - Page 9

• Manufacturer Part Number: cs43l43
• Description: Low-voltage Stereo D/a Converter With Headphone Amplifier
• Manufacturer: Cirrus Logic, Inc.

3.5 Recommended Power-up Sequence
3.6 Popguard
The CS43L43 uses Popguard
and power-down. This technology, when used with external DC-blocking capacitors in series with the au-
dio outputs, minimizes the audio transients commonly produced by single-ended single-supply converters.
It is activated inside the DAC when the RST pin is enabled/disabled and requires no other external control,
aside from choosing the appropriate DC-blocking capacitors.
DS479PP3
3.4.1 Stand-Alone Mode
When using Internal Serial Clock (see section 3.2.1), pin 3 is available for de-emphasis control and
selects the 44.1 kHz de-emphasis filter. Please see Table 6 for the desired de-emphasis control.
3.4.2 Control Port Mode
The Mode Control bits select either the 32, 44.1, or 48 kHz de-emphasis filter. Please see section
5.7.4 for the desired de-emphasis control.
3.5.1 Stand-Alone Mode
1. Hold RST low until the power supply and configuration pins are stable, and the master and
left/right clocks are locked to the appropriate frequences, as discussed in section 3.2. In this state, the
control port is reset to its default settings and VQ_HP will remain low.
2. Bring RST high. The device will remain in a low power state with VQ_HP low and will initiate
the Stand-Alone power-up sequence after approximately 1024 LRCK cycles.
3.5.2 Control Port Mode
1. Hold RST low until the power supply is stable, and the master and left/right clocks are locked to
the appropriate frequences, as discussed in section 3.2. In this state, the control port is reset to its de-
fault settings and VQ_HP will remain low.
2. Bring RST high. The device will remain in a low power state with VQ_HP low. The control port
will be accessible at this time.
3. Wait approximately 2 LRCK cycles and then perform an I
completion of approximately 1024 LRCK cycles. The desired register settings can be loaded while
keeping the PDN bit set to 1.
4. Set the PDN bit to 0. This will initiate the power-up sequence, which lasts approximately 50 µS
when the POR bit is set to 0. If the POR bit is set to 1, see Section 3.6 for for a complete description
of power-up timing.
®
Transient Control
®
technology to minimize the effects of output transients during power-up
Table 6. De-Emphasis Control
DEM
0
1
DESCRIPTION
44.1 kHz
Disabled
2
C write to the CP_EN bit prior to the
CS43L43
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