TDF8599A NXP Semiconductors, TDF8599A Datasheet - Page 16

• Manufacturer Part Number: TDF8599A
• Description: The TDF8599A is a dual Bridge-Tied Load (BTL) car audio amplifier comprising anNDMOST-NDMOST output stage based on SOI BCDMOS technology
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDF8599A_2
Product data sheet
8.5.5 DC offset protection
DC Protection (DCP) is activated when the DC content in the demodulated output voltage
exceeds a set threshold (typically 2 V). DCP is active in both Mute mode and Operating
mode.
signal is prevented using the external capacitor (C
In I
voltage shift exceeds threshold values, the offset alarm bit DB1[D2] is set and if bit
IB1[D7] is not set, diagnostic information is also given. Any detected offset shuts down
both channels when bit IB2[D7] is not set. To restart the TDF8599A in I
EN must be toggled or DCP disabled by connecting pin DCP to pin AGND.
Fig 14. DC offset protection and diagnostic output
•
•
2
During the start-up sequence:
– When the TDF8599A is switched from standby to mute (t
During operation:
– A short to one of the supply lines trips OCP causing the amplifier channel to
C-bus mode, DC offsets generate a voltage shift around the bias voltage. When the
Figure 14
circuit on one of the output terminals (i.e. between V
start-up procedure is interrupted and the TDF8599A waits for open circuit outputs.
No large currents flow in the event of a short circuit to the supply lines because the
check is performed before the power stages are enabled.
shutdown. After 50 ms the amplifier channel restarts and WP is activated.
However, the corresponding amplifier channel will not start-up until the supply line
short circuit has been removed.
IB1[D6]
shows how false triggering of the DCP by low frequencies in the audio
V to I
Rev. 02 — 30 June 2009
IB2[D6]
DB1[D2]
S
V to I
I
2
C-bus controlled dual channel class-D power amplifier
Q
IB1[D7]
IB2[D7]
S4
S3
V
switch off channels
ref
50 k
F
) to generate a cut-off frequency.
OUT1P
OUT1N
OUT2P
OUT2N
DCP
DIAG
P
or GND) is detected, the
d(stb-mute)
TDF8599A
001aak078
2
© NXP B.V. 2009. All rights reserved.
C-bus mode, pin
C F
). When a short
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