max97236 Maxim Integrated Products, Inc., max97236 Datasheet - Page 15

• Manufacturer Part Number: max97236
• Description: Audio Amplifier With Jack Detection
• Manufacturer: Maxim Integrated Products, Inc.

There are two types of keypads that can be connected
to the IC:
• A single-button hook switch or MIC switch that
• A passive multibutton headset
Two registers, 0x15 and 0x16, control the key switch
debounce time, t
The debounce time, 0x15, is the time from when the
switch stops bouncing and when the ADC converts.
The delay time, 0x16, is set long to ensure that an unplug
event is not encoded as a keypress. See
The PRESS bit alerts the system to whether the current
interrupt was caused by a button press or release.
Figure 6. Single-Button, Passive Multibutton Hook Switch/Microphone Switch Timing
grounds out the microphone bias when pressed
SINGLE BUTTON KEYPRESS OR PASSIVE MULTIBUTTON HEADSET (MBH) PLAY/MUTE, NORMAL SPEED
V
SINGLE BUTTON KEYPRESS OR PASSIVE
MULTIBUTTON HEADSET (MBH) PLAY/MUTE, FAST SPEED
V
GND
GND
BIAS
BIAS
DEB
, and delay time, t
t
ADC CONVERT
t
DEB
DEB
ADC CONVERT
Key Switch Encoder Timing
Audio Amplifier with Jack Detection
Key Switch Encoder
DELAY
The PRESS Bit
t
Figure
DELAY
t
DELAY
.
MCSW PRESS IRQ AND REPORT VALUE
9.
t
DEB
AND REPORT VALUE
MCSW PRESS IRQ
Figure 5. Passive Single-Button Hook Switch
MIC BIAS
t
DELAY
t
DEB
MAX97236
MCSW RELEASE IRQ
t
DELAY
MCSW RELEASE IRQ
15