Onkyo TA-RW255 - Dual Cassette Deck, Service Manual, Page: 47 / 106

HA12167FB/HA12169FB
25
A deck
PB EQ
REC IN VRI 1
VRI 2 VRI 3 REC OUT
PB EQ
Compensation
of low
frequency
reagion
EQ IN
EQ OUT
HA12167/9
B deck
PB REC
PB OUT
Figure 6 Application for Dubbing Deck
Injector Current
HA12167FB/HA12169FB has logic circuit which is fabricated by I
2
L into IC. To operate this circuit, it is
required enough injector current. Injector current goes into from the INJ pin (pin 38) and external resistor
is required to connect to this pin for adequate current. The value of external resistor is obtained by using
following equations. And put them with ±10% tolerance value which is calculated. V
INJ
can allow to
connect to V
CC
shown below. Large injector current fear to cause mis-operation of Logic under the
condition of high temperature. Also, small injector current fear to cause mis-operation (stop operation).
Under the condition of low temperature. Therefore, pay attention to have good stability of V
INJ
.
INJ
INJ
R
V
– 0.7
3.6
k
=
[ ]
Ω
Single supply
INJ
INJ EE
R
V
+ V – 0.7
3.6
k
=
[ ]
Ω
Split supply
Gain Control of Electronic Volume
HA12167FB/HA12169FB is designed in order to change the gain by DAC fabricated into IC. To reduce
the click noise when changing volume gain instantaneously, required to connect the capacitor and resistor
(CR time constant) to CONT pin (pin 13, 48, 68, 73). These terminals are also be used as output pin of
DAC. Therefore, by forcing voltage and current to these terminals, it is applicable to control volume gain
directly. But, voltage forced to these terminals must be from V
CC
/2 –2 V to V
CC
/2 (for split supply use, –2
V to 0 V) in this case. And, this case, change of a gain depending on a temperature gets large.
www. xiaoyu163. com
QQ 376315150
9 9
2
8 9
4 2
9 8
TEL 13942296513 9 9 2 8 9 4 2 9 8 0 5 1 5 1 3 6 7 3
Q Q
TEL 13942296513 QQ 376315150 892498299 TEL 13942296513 QQ 376315150 892498299
http://www.xiaoyu163.com
http://www.xiaoyu163.com