HA12203NT Datasheet, PDF (10/97 Pages) Hitachi Semiconductor – Audio Signal Processor for Cassette Deck(Dolby B-type NR with Recording System)

HA12203NT/HA12204NT
Reference Voltage
The reference voltage are provided for the left channel and the right channel separately. The block diagram
is shown as figure 1.
22
V_CC
+
–
V_CC
42
+
GND
–
V_EE
1
+
–
V_EE
L channel reference
Music sensor reference
R channel reference
Figure 1 Reference Voltage
Operating Mode Control
HA12203NT / 204NT provide fully electronic switching circuits. And each operating mode control is
controlled by parallel data (DC voltage).
Table 2 Control Voltage
Pin No.
Lo
Mid
12, 13, 14, 16, – 0.2 to 1.0 —
17, 18, 20
Hi
4.0 to V_CC
Unit
V
Test Condition
Input Pin
Measure
V
15, 19
– 0.2 to 1.0 2.0 to 3.0
4.0 to V_CC
V
Notes: 1. Each pins are on pulled down with 100 kΩ internal resistor.
Therefore, it will be low-level when each pins are open.
But 19 pin are mid-level when it is open.
2. Over shoot level and under shoot level of input signal must be the standardized (High: V , Low:
CC
–0.2V).
3. For reduction of pop noise, connect 1µF to 22µF capacitor with mode control pins.
But it is impossible to reduce completely in regard to Line mute, therefore, use external mute at
the same time.
Rev.3, Jun. 1999, page 10 of 97