HA12179F Datasheet, PDF (10/40 Pages) Hitachi Semiconductor – Audio Signal Processer for Car Deck and Cassette Deck(Dolby B-type NR with PB Amp)

HA12179F
Application Note
Power Supply Range
Table 1 Supply Voltage
Single supply
HA12179F
6.8 V to 16.0 V
HA12179F is designed to operate on single supply. Please consult to HITACHI sales engineers when it will
use the split supply.
1. The lower limit of supply voltage depends on the line output reference level.
The minimum value of the overload margin is specified as 12 dB by Dolby Laboratories.
2. In the reverse-voltage conditions such as 'D-GND is higher than VCC' or 'D-GND is lower than GND',
excessive current flows into the D-GND to destroy this IC. To prevent such destruction, pay attention
to the followings on using.Therefore, Short-circuit the D-GND and GND directory on the board
mounting this IC.
Reference Voltage
For the single supply operation this device provides the reference voltage of half the supply voltage that is
the signal grounds. As the peculiarity of these devices, the capacitor for the ripple filter is very small about
1/100 compared with their usual value. The Reference voltage are provided for the left channel and the
right channel separately. The block diagram is shown as figure 1.
22 _VCC
49 50
GND
40
+
RIP
C22
1µ
47 VREF (L)
+
–
L channel
reference
+
–
30 MS VREF
Music sensor
reference
+
R channel
–
reference
52 VREF (R)
Figure 1 The Block Diagram of Reference Voltage Supply
Rev.1, Apr. 1994, page 10 of 40