MC13135 MC13136
TEST CIRCUIT INFORMATION
Although the MC13136 can be operated with a ceramic
discriminator, the recovered audio measurements for both
the MC13135 and MC13136 are made with an LC quadrature
detector. The typical recovered audio will depend on the
external circuit; either the Q of the quad coil, or the RC
matching network for the ceramic discriminator. On the
MC13136, an external capacitor between Pins 13 and 14 can
be used with a quad coil for slightly higher recovered audio.
See Figures 10 through 13 for additional information.
Since adding a matching circuit to the RF input increases
the signal level to the mixer, the third order intercept (TOI)
point is better with an unmatched input (50
Ω
from Pin 21 to
Pin 22). Typical values for both have been included in the
Electrical Characterization Table. TOI measurements were
taken at the pins with a high impedance probe/spectrum
analyzer system. The first mixer input impedance was
measured at the pin with a network analyzer.
Figure 1a. MC13135 Test Circuit
VCC
0.84
µH
0.1
1.0 k
39.0
MHz
Xtal
20 p
5.0 p
3
5.0 k
4
0.1
120 p
50 p
5
2nd LO
6
7
8
9
Demod
10
0.1
0.1
12
0.1
0.1
11
15
14
13
39 k
455 kHz
Quad
Coil
39 k
Limiter
16
18
VCC2
19
0.1
360
20
Ceramic
Filter
10.7 MHz
VCC1
2
22
21
0.01
1st LO
1
Varicap
24
23
0.001
62 pF
0.2
µH
0.01
180 p
RF
Input
Figure 1.
10.245
MHz Xtal
Ceramic
Filter
455 kHz
AF
17
8.2 k
0.1
Figure 1b. MC13136 Quad Detector Test Circuit
AF
Demod
Limiter
16
15
12
0.1
14
13
455 kHz
Quad Coil
39 k
39 k
VCC
MOTOROLA ANALOG IC DEVICE DATA
3
MOTOROLA [ MOTOROLA, INC ]
