TDA8596_15 Datasheet, PDF (19/48 Pages) NXP Semiconductors – I2C-bus controlled 4 ´ 45 W power amplifier with symmetrical inputs

NXP Semiconductors
TDA8596
I²C-bus controlled 4 × 45 W power amplifier with symmetrical inputs
Example: at an AC output voltage of 2 V peak the total impedance must be less than 4 Ω
to detect an AC coupled load or above 9 Ω to guarantee the detection of a DC load. Refer
to Table 6 for the interpretation AC load detection bits.
Table 6. AC load detection translation table
Normal DC load bit
DBx[D5]
Line driver DC load bit
DBx[D4]
Don’t care
0
Don’t care
1
Load indication
no AC load detected
AC load detected
The AC load detection can only be performed when the amplifier has completed its
start-up sequence. Consequently it will not conflict with the DC load detection.
20
|Z_th(load)|
(Ω)
16
12
8
4
001aad177
(1)
(2)
0
0
1
2
3
(1) I_oM < 230 mA (no load detection level).
(2) I_oM > 460 mA (load detection level).
Fig 13. AC load impedance versus output signal
4
5
V_oM (V)
7.15 I²C-bus diagnostic bits read out
The diagnostic information of the amplifier can be read out via the I²C-bus. The I²C-bus
data bits are set in case a failure event occurs and are not reset until an I²C-bus read
command is given. This implies that even when the failure mode is removed before
reading out the I²C-bus, the microcontroller will still be able to read out what kind of failure
has occurred. A consequence of this procedure is that during the I²C-bus read cycle old
information is read. When actual information is required, it is recommended to perform
two successive read actions.
The DIAG pin will give actual diagnostic information (when selected), however it does not
distinguish between the various failure modes. The DIAG pin can be used to trigger an
I²C-bus read out of the data bits to retrieve actual diagnostic information. When a failure is
no longer present, the DIAG pin will be released instantly, independently of the I²C-bus
latches.
TDA8596_2
Product data sheet
Rev. 02 — 8 November 2007
© NXP B.V. 2007. All rights reserved.
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