MAX14579E Datasheet, PDF (9/11 Pages) Maxim Integrated Products – Low-Power Headset Detectors with SEND/END Button Support Low-Power Microphone Mode

Low-Power Headset Detectors
with SEND/END Button Support
Supported Accessories
The devices support all standard configurations of
headsets with a microphone and SEND/END button on a
TRS or TRRS 3.5mm jack. Figure 2 shows the supported
connections of the speakers, SEND/END button, and
microphone to the jack.
Headset with No Microphone
When the 3.5mm jack in Figure 2a is inserted, the MIC
input is pulled low permanently by the ground con-
nection on the sleeve and the SWD output is logic-low
permanently. This type of headset is supported by imple-
menting a timeout period in software to recognize that
the permanent logic-low is not due to a very long SEND/
END button press event.
Headset with Microphone and Normally
Open SEND/END Button in Parallel
When the 3.5mm jack in Figure 2b is inserted, the MIC
input is pulled below the threshold only during a SEND/
END button press event. The SWD output is logic-high
when the SEND/END button is pressed for more than the
debounce time.
Headset with Normally Open SEND/END Button
and Resistive Remote Control
The devices support the 3.5mm jack with a microphone
and two buttons in Figure 2c that is the standard Windows
Mobile™ configuration. The threshold is set to detect a
button press, regardless of which button is pressed.
High-ESD Protection
Electrostatic discharge (ESD)-protection structures are
incorporated on all pins to protect against electrostatic
discharges up to Q2kV Human Body Model (HBM)
encountered during handling and assembly. DETIN
and MIC are further protected against ESD up to Q15kV
(HBM) without damage. After an ESD event, all the
devices continue to function without latchup.
12 3 4
SPEAKER
SPEAKER
(a)
12 3 4
SPEAKER
SPEAKER
(b)
12 3 4
SEND/
END
MICROPHONE
SPEAKER
SPEAKER
SEND/
END
600Ω 200Ω ^MICROPHONE
(c)
Figure 2. Supported 3.5mm Accessory Configurations
Windows Mobile is a registered trademark of Microsoft Corporation.
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