MAX13301 Datasheet, PDF (28/37 Pages) Maxim Integrated Products – 4-Channel, Automotive Class D Audio Amplifier Feedback After the Filter

4-Channel, Automotive Class D Audio Amplifier
Table 29. Status Register 3
BIT #
NAME
OSTAT3
7
6
5
4
3
2
1
0
—
—
—
VER
VOS3
VOS2
VOS1
VOS0
Table 30. Status Register 3 Bit Description
BIT
BIT DESCRIPTION
VER
Version Indicator.
0 = Reserved
1 = MAX13301
VOS[3:0]
Offset Voltage Indicator. VOS[3:0] indicates whether an offset voltage exists between the differential outputs.
Read this bit in play mode after precharge with no signal on the input. This bit is not latched and is not a
valid indicator of offset when an input signal is present. An offset voltage indicator is available for each out-
put: VOS3 is for output 3, VOS2 is for output 2, etc.
0 = The differential offset voltage between OUT_+ and OUT_- exceeds Q1V (typ).
1 = The differential offset voltage between OUT_+ and OUT_- is within Q1V (typ).
Table 31. Fault Conditions
FAULT
Overvoltage
MONITORING STATE
All
Undervoltage (PVDD)
Charge-Pump Undervoltage
Normal, Standby
Normal
Overtemperature Shutdown
Overtemperature Warning
Normal, Standby
Normal
Open Load
Shorted Load
Normal
Normal
Short-to-Ground/Battery
Clip Output
Overcurrent
DC Offset
Normal
Normal
Normal
Normal, No Music
REPORTING METHOD
I²C, FLT_OT
I²C, FLT_OT
I²C
I²C, FLT_OT
I²C, FLT_OT
I²C
I²C
I²C, FLT_OT
I²C, CL0, MUTE_CL1
I²C, FLT_OT
I²C
ACTION
OUT_ to 1/2 VPVDD
High-Z All
High-Z All
High-Z All
None
None
High-Z Channel
High-Z Channel
None
High-Z Channel
None
LATCHED
No
No
No
No
No
No
Yes
Yes
No
Yes
No
Fault Detection
The device integrates fault detection and protection
circuitry. Table 31 lists all fault events that each device
can encounter, the modes in which they are detected,
the method with which they are reported, the devices'
response to them, and whether they cause the outputs
to latch into a high-impedance state.
Load Diagnostics
The device incorporates built-in diagnostics to detect
external wire harness faults that can occur during instal-
lation or over time. Load diagnostics include short circuit
to ground or battery, shorted or open speaker, and
open tweeter. Load diagnostics can be run at any time
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when the device is in normal mode (i.e., not in standby
mode) with the outputs three-stated. The presence of
any of these faults is indicated by software through the
status registers and by hardware through the CL0 and
MUTE_CL1 open-drain outputs if the status bits have
been mapped to the outputs.
Short-to-Ground/Battery Diagnostic
The diagnostic for short-to-battery and ground is done
with CTRL3.SDET = 1. None of the results are latched
so the OSTAT2 register must be read while running this
diagnostic to get a valid status.
If the load is present, a short on either of the differential
outputs results in a short on the other output. Therefore,