sta335bwqs STMicroelectronics, sta335bwqs Datasheet - Page 29

• Manufacturer Part Number: sta335bwqs
• Description: 2.1-channel High-efficiency Digital Audio System With Qsound Qhd?
• Manufacturer: STMicroelectronics

STA335BWQS
7.1.3
7.1.4
7.1.5
Thermal warning recovery bypass
Table 14.
If the thermal warning adjustment is enabled (TWAB = 0), then the thermal warning
recovery determines if the -3 dB output limit is removed when thermal warning is negative.
If TWRB = 0 and TWAB = 0 then, when a thermal warning disappears, the -3 dB output limit
is removed and the gain is added back to the system. If TWRB = 1 and TWAB = 0, then
when a thermal warning disappears the -3 dB output limit remains until TWRB is changed to
zero or the device is reset.
Thermal warning adjustment bypass
Table 15.
The on-chip STA335BWQS power output block provides feedback to the digital controller
using inputs to the power control block. The TWARN input is used to indicate a thermal
warning condition. When TWARN is asserted (set to 0) for a period of time greater than
400 ms, the power control block forces a -3 dB output limit (determined by TWOCL in
coefficients RAM) to the modulation limit in an attempt to eliminate the thermal warning
condition. Once the thermal warning output limit adjustment is applied, it remains in this
state until reset, unless FDRB = 0.
Fault detect recovery bypass
Table 16.
The on-chip STA335BWQS power output block provides feedback to the digital controller
using inputs to the power control block. The FAULT input is used to indicate a fault condition
(either over-current or thermal). When FAULT is asserted (set to 0), the power control block
attempts a recovery from the fault by asserting the 3-state output (setting it to 0 which
directs the power output block to begin recovery), holds it at 0 for period of time in the range
of 0.1 ms to 1 s as defined by the fault-detect recovery constant register (FDRC registers
0x29, 0x2A), then toggles it back to 1. This sequence is repeated as log as the fault
indication exists. This feature is enabled by default but can be bypassed by setting the
FDRB control bit to 1.
Bit
Bit
Bit
5
6
7
R/W
R/W
R/W
RW
RW
RW
TWRB
TWAB
FDRB
RST
RST
RST
1
1
0
TWRB
TWAB
Name
Name
Name
FDRB
0: Thermal warning recovery enabled
1: Thermal warning recovery disabled
0: Thermal warning adjustment enabled
1: Thermal warning adjustment disabled
0: fault detect recovery enabled
1: fault detect recovery disabled
Description
Description
Description
Register description
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