MAX97236EVKIT+ Maxim Integrated Products, MAX97236EVKIT+ Datasheet - Page 35

• Manufacturer Part Number: MAX97236EVKIT+
• Description: Audio Modules & Development Tools MAX97236 Eval Kit
• Manufacturer: Maxim Integrated Products

Specifications of MAX97236EVKIT+

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Table 18. Status Bits Relation to Enable Bits
Power-Up, AUTO = 0x02:
1) Wait for JKIN to set.
2) Detection runs automatically, so wait for DDONE to set.
3) Read the Status registers to find out what was detected.
4) The IC is automatically placed in standby mode after
5) Pull SHDN high to turn on the IC.
6) The appropriate enable bits were automatically set
7) Read the Enable1 and Enable2 registers to see what
When AUTO = 0x01 or 0x02, the IC automatically
enables the required blocks according to what has been
detected. In case AUTO = 0x00, it is required that all
the correct blocks are enabled for unplug detection to
work properly.
enable bits for the blocks that are (need to be) enabled
for proper operation.
Power-Down, All AUTO Settings:
If audio is playing and VSEN = 0:
1) Set the headphone volume register mute bits or set
2) The VOL bit is set when the volume slew is done.
3) Pull SHDN low to go into standby mode; the current
If audio is not playing:
1) Set VSEN = 1 to disable volume slewing. If this is not
detection is done.
because AUTO = 0x02.
was turned on.
code 0x00 as the volume.
Make sure IVOL is set so that an interrupt is flagged.
jack case is remembered. Cycle RESET (low ➝ high
➝ low) to run jack detection and configuration again.
done, the volume slew down at a rate of 1ms per vol-
ume step.
STATUS BIT
MIC_IN
LINE_L
LINE_R
HP_L
HP_R
Table 18
correlates the status bits with the
Audio Amplifier with Jack Detection
ENABLE BIT
MIC_BIAS
MIC_AMP
RGHEN
RGHEN
LFTEN
LFTEN
KS
2) Set the headphone volume register mute bits or set
3) Pull SHDN to 0 to go to standby mode; the current
Proper layout and grounding are essential for optimum
performance. Use large traces for the power-supply
inputs and amplifier outputs to minimize losses due to
parasitic trace resistance, as well as route heat away
from the device. Good grounding improves audio per-
formance, minimizes crosstalk between channels, and
prevents switching noise from coupling into the audio
signal. Connect PGND and GND together at a single
point on the PCB. Route PGND and all traces that carry
switching transients away from GND, and the traces and
components in the audio signal path.
Place the charge-pump capacitors as close as possible
to the device. Bypass PVDD and PVSS with a 1FF capac-
itor to PGND. Place the bypass capacitors as close as
possible to the device.
Route the pins that connect to the jack on wide, low-
impedance traces whenever possible. RING2 or SLEEVE
ends up being the load’s ground connection; ground
impedance causes excess crosstalk and noise pickup.
Route the EXTCLK traces away from low-level audio
input nodes and the microphone bias bypass connection
to keep the audio as noise free as possible.
PGND and GND pins need to have as low an impedance
connection to the ground plane. This means liberal use
of vias and a solid ground plane.
The maximum resistance between the pins TIP and RING1
to the headphone jack should not exceed 3I.
The maximum resistance between RING2 and SLEEVE to
the headphone jack should be 0.5I or better. RING2 or
SLEEVE is used as the common connector in a headset
or headphone. Any impedance on this path decreases
crosstalk performance.
A bulk 10FF capacitor is required for proper charge-
pump operation. The capacitors are readily available in
0603 packages in the necessary voltage rating. Bypass
V
DD
code 0x00 as the volume, and the amplifiers mute
immediately.
jack case is remembered. Cycle RESET (low ➝ high
➝ low) to run jack detection and configuration again.
to PGND with 10FF.
PCB Layout and Grounding
Power-Supply Bypassing
35