HA12226F Datasheet, PDF (15/86 Pages) Hitachi Semiconductor – Audio Signal Processor for Cassette Deck(Dolby B-type NR with Recording System)

HA12226F/HA12227F
REC Equalizer
The outlines of REC Equalizing frequency characteristics are shown by figure 9. Those peak level can be
set up by supplying voltage. (0 V to 5 V, GND = 0 V) to pin 10 (GPCAL).
And whole band gain can be set up by supplying voltage (0 V to 5 V, GND = 0 V) to pin 11 (RECCAL).
Both setting up range are ±4.5 dB. In case that you do not need setting up, pin 10, pin 11 should be open
bias.
Note:
Depending on the employed REC/PB head and test tape characteristics, there is a rare case that the
REC-EQ characteristics of this LSI can not be matched to the required characteristics because of
built-in resistors which determined the REC-EQ parameters in this care, please inquire the
responsible agent because of the adjustment of built-in resistor is necessary.
RECCAL
GPCAL
Frequency (Hz)
Figure 9 Frequency Characteristics of REC Equalizer
Bias Switch
The HA12215F built-in DC voltage generator for bias oscillator and its bias switches.
External resistor R20, R21 which corresponded with tape positions and bias out voltage are relater with
below.
Vbias =^..
R22
(R20 or R21) + R22
× (V_CC − 0.7)
[V]
Bias switch follows to a logic of pin 19 (B / Norm / Crom).
Note: A current that flows at bias out pin, please use it less than 5 mA.
Rev.6, Dec. 2000, page 15 of 86