HA12167FB Datasheet, PDF (24/73 Pages) Hitachi Semiconductor – Audio Signal Processor for Cassette Deck (Deck 1 Chip)

HA12167FB/HA12169FB
A deck
PB EQ
Compensation
of low
frequency
reagion
PB EQ
B deck
VRI 2 VRI3
REC OUT
REC IN VRI 1
HA12167/9
EQ IN
EQ OUT
REC
PB
PB OUT
Figure 6 Application for Dubbing Deck
Injector Current
HA12167FB/HA12169FB has logic circuit which is fabricated by I²L 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.
R_INJ
=
VINJ – 0.7
3.6
[kΩ]
Single supply
[ ] R_INJ
=
VINJ +
VEE
3.6
–
0.7
kΩ
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.
Rev.3, Jun. 1997, page 24 of 73