Advance Information Low Power

Narrowband FM IF

The MC3371 and MC3372 perform single conversion FM reception and consist of an oscillator, mixer, limiting IF amplifier, quadrature discrimi-nator, active filter, squelch switch, and meter drive circuitry. These devices are designed for use in FM dual conversion communication equipment.

The MC3371/MC3372 are similar to the MC3361/MC3357 FM IFs, except that a signal strength indicator replaces the scan function controlling driver which is in the MC3361/MC3357. The MC3371 is designed for the use of parallel LC components, while the MC3372 is designed for use with either a 455 kHz ceramic discriminator, or parallel LC components.

These devices also require fewer external parts than earlier products.

The MC3371 and MC3372 are available in dual-in-line and surface mount packaging.

• Wide Operating Supply Voltage Range: VCC =2.0 to 9.0 V

• Input Limiting Voltage Sensitivity of -3.0 dB

• Low Drain Current: ICC = 3.2 mA, @ VCC = 4:0 V, Squelch Off

• Minimal Drain Current Increase When Squelched

• Signal Strength Indicator: 60 dB Dynamic Range

• Mixer Operating Frequency Up to 100 MHz

• Fewer External Parts Required than Earlier Devices MAXIMUM RATINGS

Devices should not be operated at these values. The "Recommended Operating Conditions" table provides conditions for actual device operation.

RECOMMENDED OPERATING CONDITIONS

Rating Pin Symbol Value Unit

Intermediate Frequency - fif 455 kHz

Limiter Amp Input Voltage 5 Vif

o

to 400 mVrms

subject to change without notice.

MC3371.MC3372

SILICON MONOLITHIC INTEGRATED CIRCUIT

PSUFFIX PLASTIC PACKAGE

CASE 648

,.# _,

D SUFFIX PLASTIC PACKAGE

CASE 7518

ORDERING INFORMATION Temperature

Device Range Package

MC3371D SO-16

MC3371P Plastic DIP

- 30· to + 70·C

MC3372D SO-16

MC3372P Plastic DIP

MOTOROLA COMMUNICATIONS DEVICE DATA

AC ELECTRICAL CHARACTERISTICS (VCC ~ 4.0 Vdc, fo ~ 5B.1125 MHz, df ~ ±3.0 kHz, fmod ~ 1.0 kHz, 50 n source, flocal

~ 57.6575 MHz, Vlocal ~ 0 dBm, TA ~ 25'C unless otherwise noted)

Characteristic Pin Symbol Min

Input for 12 dB SINAD - VSIN

Matched Input - (See Figures 10, 11 & 12)

-Unmatched Input - (See Figures 7A & 7B)

-Input for 20 dB NOS

-

^VNOS

-Recovered Audio Output Voltage

-

^AFO

Vrf ~ -30 dBm 120

Recovered Audio Drop Voltage Loss - AFloss

Vrf ~ -30 dBm, VCC ~ 4.0 V to 2.0 V -B.O

Mixer Conversion Gain

-

^AV(Mix)

Vrf ~ -40 dBm, RL ~ 1.B kn 14

Signal to Noise Ratio - sin

Vrf ~ -30 dBm 36

Total Harmonic Distortion

-

^THO

Vrf ~ -30 dBm, BW ~ 400 Hz to 30 kHz

-Detector Output Impedance 9

Zo

-Detector Output Voltage (No Modulation) 9 DVO

Vrf ~ -30 dBm

-Meter Drive 13 MO

Vrf ~ -100 to -40 dBm

-Meter Drive Dynamic Range 13 MVD

RFln

-IFln (455 kHz)

-Mixer Third Order Input Intercept Point - ITOMix

f1 ~ 58.125 MHz

f2 ~ 58.1375 MHz

-Mixer Input Resistance 16 Rin

-Mixer Input Capacitance 16 Cin

-DC ELECTRICAL CHARACTERISTICS (VCC ~ 40 Vdc TA ~ 25'C, unless otherwise noted)

Characteristic Pin Symbol Min

Drain Current (No Input Signal) 4

Filter Output (No Input Signal) 11

DC Voltage V11 1.5

Voltage Change, VCC ~ 2.0 to 9.0 V dV" 2.0

Trigger Hysteresis

-

Hys 34

MOTOROLA COMMUNICATIONS DEVICE DATA

Typ

TYPICAL CURVES (UNMATCHED INPUT)

FIGURE 1 - TOTAL HARMONIC DISTORTION versus TEMPERATURE

TA. AMBIENT TEMPERATURE ('e)

FIGURE 3 - RSSI OUTPUT versus TEMPERATURE

30dBm

TA. AMBIENT TEMPERATURE ('e)

FIGURE 5 - MIXER GAIN versus SUPPLY VOLTAGE

TAI=

+7~'e-

1:::=

FIGURE 2 - RSSI versus RF INPUT

0

TA~

^+wk.

FIGURE 4 - MIXER OUTPUT versus RF INPUT

I 100lMHZ

/'"

FIGURE 6 - MIXER GAIN versus FREQUENCY 40

f. FREOUENCY

(MHz)-MOTOROLA COMMUNICATIONS DEVICE DATA

FIGURE 7A - MC3371 FUNCTIONAL BLOCK DIAGRAM AND TEST FIXTURE SCHEMATIC

RF Input

VCC = 4.0Vdc

Cl

0.01 51

16 15

51 k

Mute

RSSIOutput

0.1

13

muRata CFU455D2

or equivalent

MOTOROLA COMMUNICATIONS DEVICE DATA

SQln

12

Filter In Filter Out 1 1

1 1 470

510 k

8.2 k

51 k 53 k

7

0.1 0.1 20 k

AFOut to Audio O.01

J

^{Power Amp}

r---,

I Quad Coil TOKO

I + ^I

2A6597 HK 110 mml I

I

^or

I I 7MC·8128Z 17 mml L _ _ _ ...J

Units:

R:fl,C: IJ.F Unless otherwise noted, capacitors marked "sm"

are silver mica.

MC3371.MC3372 2-81

FIGURE 7B - MC3372 FUNCTIONAL BLOCK DIAGRAM AND TEST FIXTURE SCHEMATIC

AF Input

VCC = 4,0 Vdc

C1 0,01

MC3371.MC3372 2·82

16

51 k 51

15

Mute

ASSIOutput

0,1

13

muAata CFU455D2

or equivalent

SO In Filter Out

11

12

Filter In

11

470 510 k

51 k 53k

C14 27p

8,2 k

A12 4,3 k

I

C15 ^0,1

O.D1

J

Units:

AFOut to Audio Power Amp

Ceramic

o

^Resonator

muAata CDB455C16

A: n, C: JLF Unless otherwise noted, capacitors marked "sm"

are silver mica.

MOTOROLA COMMUNICATIONS DEVICE DATA

PIN DESCRIPTION

OPERATING CONDITIONS VCC

=

4.0 Vdc, RFln

=

100 JLV, fmod

=

1.0 kHz, fdev

=

3.0 kHz. MC3371 at fRF

=

10.7 MHz (see re 10).

OSCI

2 OSC2

3 _MXOut

4 VCC

5 IFln

6 DECI

7 DEC2

Internal Equivalent Circuit

Vcc

15 k OSC1 ...

~,...Nv-05C2

MixerOut

IFln

DECI DEC2

MOTOROLA COMMUNICATIONS DEVICE DATA

The base of the Colpitts oscillator. Use a high impedance and low capacitance probe or a "sniffer" to view the wave-form without altering the frequency.

Typical level is 450 mVp-p.

The emitter of the Colpitts oscillator.

Typical signal level is 200 mVp-p. Note that the signal is somewhat distorted compared to that on pin 1.

Output of the Mixer. Riding on the 455 kHz is the RF carrier component.

The typical level is approximately 60mVp-p.

Supply Voltage - 2.0 to 9.0 Vdc is the operating range. VCC is decoupled to ground.

Input to the IF amplifier after passing through the 455 kHz ceramic filter. The signal is attenuated by the filter. The typical level is approximately 50 mVp-p.

IF Decoupling. External 0.1 JLF capaci-tors connected to VCC.

MC3371.MC3372 2-83

PIN DESCRIPTION

OPERATING CONDITIONS VCC = 4.0 Vdc, RFln = 100 ,.,V, fmod = 1.0 kHz, fdev = 3.0 kHz. MC3371 at fRF = 10.7 MHz (see 10).

Pin Symbol 8

9

10

11 Quad

Coil

RA

Filln

FilOut

MC3371.MC3372 2·84

Internal Equivalent Circuit

Vcc

Quad Coil VCC

RAOut

~ VCC240"'A

FilterOut 11

Description Quadrature Tuning Coil. Composite (not yet demodulated) 455 kHz IF signal is present. The typical level is 500 mVp-p.

Recovered Audio. This is a composite FM demodulated output having signal and carrier component. The typical level is 1.4 Vp-p.

The filtered recovered audio has the carrier component removed and is typically 800 mVp-p.

Filter Amplifier Input

Filter Amplifier Output. The typical signal level is 400 mVp-p.

Waveform

MOTOROLA COMMUNICATIONS DEVICE DATA

PIN DESCRIPTION

OPERATING CONDITIONS VCC

=

4.0 Vdc, RFln

=

100 /LV, fmod

=

1.0 kHz, fdev

=

3.0 kHz. MC3371 at fRF

=

10.7 MHz (see ure 10).

Pin Symbol

13 RSSI

14 MUTE

15 GND

16 MIXln

Internal Equivalent Circuit

~

Vee

Bias

13 RSSIOut

K"'",::'

40 k

':" ":'

GND 15

~ ^~

Vee

~

Mixerl"

3.3 k 10 k

MOTOROLA COMMUNICATIONS DEVICE DATA

Description Squelch Input. See discussion in application text.

RSSI Output. Referred to as the Received Signal Strength Indicator or .ASSI. The chip sources up to 60 /LA

over the linear 60 dB range. This pin may be used many ways, such as:

AGe, meter drive and carrier triggered squelch circuit.

Mute Output. See discussion in application text.

Ground. The ground area should be continuous and unbroken. In a two-sided layout, the component side has the ground plane. In a one-sided lay-out, the ground plane fills around the traces on the circuit side of the board and is not interrupted.

Mixer

Input-Series Input Impedance:

(C, 10 MHz: 309 -j33 n

«,

45 MHz: 200 - j13

n

MC3371oMC3372 2·85

PIN DESCRIPTION

OPERATING CONDITIONS VCC = 4.0 Vdc, RFln = 100 }1V, fmod = 1.0 kHz, fdev = 3.0 kHz. MC3372 at fRF = 45 MHz (see Figure 121.

Pin Symbol 5

6 DECl

7 IFOut

8 Quadl n

9 RA

Internal Equivalent Circuit

IFln~

^{6 53 k}

DEC

60 }1A

Dans le document Device Data (Page 103-111)