92HD66B Datasheet, PDF (34/286 Pages) Integrated Device Technology – FOUR CHANNEL HD AUDIO CODECS

92HD66B
FOUR CHANNEL HD AUDIO CODECS WITH DUAL CAPLESS HEADPHONE AMPLIFIERS
2.25. Digital Core Voltage Regulator
The digital core operates from 1.8V (+/- 10%). Many systems require that the CODEC use a single
3.3V digital supply, so an integrated regulator is included on die. The regulator uses pin 9, DVDD, as
its voltage source. The output of the LDO is connected to pin 1 and the digital core. A 10uF capacitor
must be placed on pin 1 for proper load regulation and regulator stability.
The digital core voltage regulator is only dependent on DVDD. DVDDIO may be either 3.3 or 1.5V
and may precede or follow DVDD in sequence. The CODEC digital logic and I/O (unless referenced
to AVDD) will operate in the absence of AVDD. DVDD and AVDD supply sequencing for the applica-
tion of power and the removal of power is neither defined nor guaranteed. It is common for desktop
systems to supply AVDD from the system standby supply and the CODEC will tolerate, indefinitely,
the condition where AVDD is active but DVDD and DVDDIO are inactive.
2.26. Analog Core Voltage Regulator
Many systems provide only a noisy 5 volt supply that is inappropriate for analog audio so an inte-
grated regulator is included on die to generate the core analog supply of 4.5V. The regulator uses
AVDD1 as its voltage source. A 10uF capacitor must be placed on the LDO output pin for proper
load regulation and regulator stability. 92HD66B may be ordered with the analog core LDO enabled
(5V operation) or bypassed (3.3V operation).
2.27. Combo Jack
The codec implements a sophisticated microphone detection algorithm to differentiate between
headphones and headsets when implementing 4-conductor “combo” jacks. A programmable sense
window (2s to ∞) provides flexibility in managing problematic slow plug insertions and partial inser-
tions. Programmable de-bounce, anti-pop delay, and headphone-microphone unsolicited response
delay controls help ensure a robust, pleasing, experience for the end user. Support for a lanyard
(“turbo”) switch using IDT’s driver further enhances combo-jack implementations by supporting
many common cellular headsets.
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92HD66B