MC13030

6

MOTOROLA ANALOG IC DEVICE DATA

PIN FUNCTION DESCRIPTION

Pin No.

Internal Equivalent Circuit

Description

1, 2

12

10 k

10 k

3.3 V

6.6 mA

150

150

Mixer1 Input

Pins 1 and 2 are equivalent. In the application circuit, 2 is grounded

with a capacitor and 1 is the input. If a load resistor is needed for the

input filter, it can be placed across Pins 1 and 2. Input impedance for

each pin is 10 k. IP3 (third order intercept) at the input is 20 dBm

(127 dB

µ). To guarantee –50 dB IM3, the input level should not be

greater than 3.5 dBm (103 dB

µ) (150 mVrms).

3

3

RF Ground

This should be connected to the ground used for the RF circuits.

4

4

5

10 k

5.1 V

4.0 V

3.4 k

FET RF AGC Output

This is the AGC for the cascode transistor connected to the RF amplifier

FET. The no–signal voltage is 5.1 V. The voltage decreases with

increasing input signals. A bypass capacitor and electrolytic capacitor

must be added to filter out RF signals on the transistor and audio signals

in the AGC signal. See Figures 4 and 5.

5

5

100

22 k

VCC

330

RF AGC2 Output

The voltage on this pin starts at 0 and increases with increasing input

signals. It is normally used to turn on diodes or a transistor connected

across the antenna input and is AGC delayed until Pin 6 reaches 2.7 V.

If the voltage on Pin 5 decreases below 2.0 V, the voltage on this pin will

decrease from 3.1 down to about 1.5 V. The maximum output current is

about 850

µA.

6

6

330

AGC

1.0 k

39 k

3.3 k

RF AGC Adjust

An electrolytic capacitor of 1.0

µF must be connected to prevent audio

modulation of the AGC circuits. If there is no resistor on this pin, the RF

AGC starts at an input level to Mixer1

≈ 40 mVrms or Mixer2 ≈ 2.0 mVrms.

Connecting a resistor from Pin 6 to ground increases RF levels required

for AGC to start. It should be used to set the desired AGC level of Mixer2.

If a resistor is not connected to Pin 6, unwanted RF signals will cause the

AGC to start at a very low level, and desired signals may be suppressed.

7

7

500

1.5 k

Mixer1 RF Level Adjust

A resistor from Pin 7 to ground will increase the gain of an amplifier from

the input of Mixer1 to the AGC circuit. It can be used to set the RF AGC

level of Mixer1. The minimum value of R7 is about 680

Ω.

8

8

510

3.3 k

SD

S

Station Detector Signal Level Adjust

A voltage on Pin 8 will set the desired signal strength at which the SD IF

Out on Pin 10 appears. The other input to this comparator is the S (signal

strength) signal. If Pin 8 is grounded, a square wave of the 2nd IF (usually

450 of 455 kHz) is present with very small input levels. This output could

also be used to drive an FM detector if desired.

9

9

IF Ground

Pin 9 is the ground for the IF section.