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CXA3117AN

Application Note

1) Power Supply

The CXA3117AN, with the built-in regulator, is designed to permit stable operation at the wide range of

2) Oscillator Input

Oscillator input method

a) Using Pins 1 and 2, input self-excited oscillation signal through the composition of a Colpitts type crystal

b) Directly input a local oscillation signal to Pin 1.

2

3

1

Ceramic

filter

2

3

1

From

local signal

Ceramic

filter

Fig. 1

3) Mixer

The mixer is of double-balance type. Pin 24 is the input pin. Input though a suitable matching circuit. The

input impedance is 2.0k

Ω.

Pin 3 serves as the output pin for the mixer, and a load resistance of 1.5k

Ω is incorporated.

4) IF Filter

The filter to be connected between this mixer output and the IF limiter amplifier input should have the

I/O impedance : 1.5k

Ω ±10%

Bandwidth

: Changes according to applications.

5) IF Limiter Amplifier

The gain of this IF limiter amplifier is approximately 100dB. Take notice of the following points in making

connection to the IF limiter amplifier input pin (Pin 5).

a) Wiring to the IF limiter amplifier input (Pin 5) should be as short as possible.

b) As the IF limiter amplifier output appears at QUAD (Pin 8), wiring to the ceramic discriminator connected

to QUAD should be as short as possible to reduce the interference with the mixer output and IF limiter

amplifier input.

Wire as short and apart as possible

As short as possible

3

4

5

6

7

8

9

Fig. 2