NOTES
REDUCED SUPPORT COMPONENTS
The AD1986’s many improvements reduce external support
components for particular applications.
• Multiple Microphone Sourcing: The MIC_1/2, LINE_IN
and C/LFE pins may all be selected as sources for
microphone input (boost amplifier).
• Multiple VREF_OUT Pins: Each microphone-capable pin
group (MIC_1/2, LINE_IN and C/LFE) has separate,
software controllable VREF_OUT pins, reducing the need
for external biasing components.
• Internal Microphone Mixing: Any combination of the
MIC_1/2, LINE_IN and C/LFE pins may be summed to
produce the microphone input. This removes the need for
external mixing components in those applications that
externally mixed microphone sources.
AD1986
• Advanced Jack Presence Detection: Using two CODEC
pins, eight resistors and isolated switch jacks, the AD1986
can detect jack insertion on eight separate jacks. Previous
CODECs would have required 8 CODEC pins and
16 resistors.
• Internal Microphone/Line In/C/LFE Sharing: On systems
that share the microphone with the C/LFE jack there are
no external components required. The micro-phone
selector can select the LINE_IN pins in those cases where
the microphone and line input devices are swapped.
• Internal Line In/Microphone/Surround Sharing: On
systems that share the line in with the surround jack there
are no external components required.
• Dual Headphone Amplifiers: The AD1986 can drive
headphones out of the HP_OUT or LINE_OUT pins.
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