TK15329 Datasheet, PDF (6/16 Pages) TOKO, Inc – Audio Analog Switch

TK15329
TEST CIRCUITS AND METHODS (CONT.)
RESIDUAL NOISE (FIGURE 7)
This value is not S/N ratio. This is a noise which occurs from
the device itself.
1) Connect V_CC to Pin 5, Pin 8 is the open condition or low
level.
2) Connect an AC volt meter to Pin 3.
3) Connect a capacitor from Pin 4 to GND.
4) Measure AC voltage of Pin 3. This value is the noise of
1-Ach. If the influence of noise from outside exists, use
optional filters.
5) Next, reverse conditions at Pin 5 and Pin 8.
6) Connect to GND through a capacitor from Pin 2.
7) Measure in the same way.
This value is the noise level of 1-Bch.
ISOLATION (FIGURE 8)
This is the cross talk between Ach and Bch.
1) Connect V_CC to Pin 8, Pin 5 is in the open condition or
low level.
2) Connect AC volt meters to Pin 4 and Pin 3.
3) Connect a capacitor and a resistance in series to GND
from Pin 2.
4) Input a sine wave (10 kHz, 1 Vrms) to Pin 4.
5) Measure the level of Pin 4 and name this V4.
6) Measure the level of Pin 3 and name this V3.
7) Calculate:
ISO = 20 Log (V3 / V4)
This value is the isolation to Bch from Ach.
8) Next, reverse conditions at Pin 5 and Pin 8.
9) Change line of Pin 2 and Pin 4.
10) Input the same sine wave to Pin 2.
11) Measure and calculate in the same way.
This value is the isolation to Ach from Bch.
VCC
VCC
+
+
+
10 K
+
+
Figure 7
Figure 8
Page 6
June 1999 TOKO, Inc.