STAC9250 Datasheet, PDF (17/137 Pages) Integrated Device Technology – TWO-CHANNEL HD AUDIO CODEC WITH MODEM & DUAL DIGITAL MICROPHONE INTERFACES

STAC9250/9251
TWO-CHANNEL HD AUDIO CODEC WITH MODEM & DUAL DIGITAL MICROPHONE INTERFACES
PC AUDIO
3.6. Headphone Drivers (Restrictions)
It is not recommended that users operate both Port A and Port D as headphone drivers simulta-
neously. Using both ports as headphone drivers degrades the signal quality of both outputs.¹
Note: 1) Headphone capabilities are on Port A (pins 39/41) and Port D (pins 35/36). Do NOT put
headphone loads on both sets of pins at the same time.
3.7. Universal Jacks™
IDT’s Universal Jacks™ technology allows for flexibility in board design and implementation.
On the STAC9250/9251, only one function can be selected at a time. A set of pins cannot be set as
input and output at the same time. However, the selected function can be changed at any time.
For the STAC9250/9251, the Universal Jacks capabilities are as follows
• All of the STAC9250/9251 ports support:
• Line Out
• Line In
• Mic with 0/10/20/30/40² dB Mic Boost
• Ports A and D also support:
• Headphone Out¹
Note: 1) Headphone capabilities are on Port A (pins 39/41) and Port D (pins 35/36). Do NOT put
headphone loads on both sets of pins at the same time.
Note: 2) When the 40dB mic boost feature is enabled, additional gain increases greater than 6dB
may result in significant audio quality degradation of the microphone audio input. In particular,
when the 40dB MIC boost is active, the SNR, THD+N and DC offset will significantly degrade
regardless of the input signal level.
IDT™
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TWO-CHANNEL HD AUDIO CODEC WITH MODEM & DUAL DIGITAL MICROPHONE INTERFACES
STAC9250/9251
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