Motorola MC3374FTB Datasheet

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. . . with single conversion circuitry including oscillator, mixer, IF amplifiers,
limiting IF circuitry, and quadrature discriminator. The MC3374 is perfect for
narrowband audio and data applications up to 75 MHz which require
extremely low power consumption. Battery powered applications down to
VCC = 1.1 V are possible. The MC3374 also includes an on–board voltage
regulator, low battery detection circuitry, a receiver enable allowing a power
down Sleep–Mode, two undedicated buffer amplifiers to allow
simultaneous audio and data reception, and a comparator for enhancing
FSK (Frequency Shift Keyed) data reception to 1200 baud.

• Low Supply Voltage: V

• Low Power Consumption: P

• Input Bandwidth 75 MHz

• Excellent Sensitivity: 0.5 µVrms for 12 dB SINAD

• Voltage Regulator A vailable (Source Capability 3.0 mA)

• Receiver Enable to Allow Active/Standby Operation

• Low Battery Detection Circuitry

• Self Biasing Audio Buffer

• Data Buffer

• FSK Data Shaping Comparator

• Standard 32–Lead QFP Surface Mount Package

Sleep–Mode is a trademark of Motorola, Inc.

= 1.1 to 3.0 Vdc

CC

= 1.5 to 5.0 mW

D

Order this document by MC3374/D



LOW VOLTAGE

SINGLE CONVERSION

FM RECEIVER

SEMICONDUCTOR

TECHNICAL DATA

32

1

FTB SUFFIX

PLASTIC PACKAGE

CASE 873

(Thin QFP)

ORDERING INFORMATION

Tested Operating

Device

MC3374FTB TA = –10° to +70°C TQFP–32

Temperature Range

Package

IF Gnd

V

CC2

1

2

3

4

5

6

7

8

Osc Base

Osc Emit

Isrc Dcpl

Rec Audio

Demodulator Decoupling

Quad T ank

*Internal Connection, do not ground.

Simplified Block Diagram

Data

Osc

MixerInMixer

Dcpl

32 31 30 29 28 27 26 25

Low

Pass

Output
Buffer

Filter

Quadrature

Demodulator

9 101112131415 16

Quad

Demod

T ank

Gnd

This device contains 87 active transistors

Mixer

Dcpl

2nd IF

Main

Current

Reference

Comp.

2nd IF

In

I/P

Out

Mixer

*N/C *N/C Comp

Buffer

Out

Data
Buffer

Voltage

Reference

Receiver

Enable

Comp

O/P

Enable

Data

Buffer

Rec

1st IF

In

1st IF

Audio
Buffer

Battery

Detector

Voltage

Reference

Regulator

Reference

Out

Low

T est

24

V

CC3

23

1st IF In

22

Audio Buffer Out

21

Audio Buffer In

20

Low Battery Detector

19

1.2 V Select

V

18

CC

17

V

reg

MOTOROLA ANALOG IC DEVICE DATA

 Motorola, Inc. 1996 Rev 0

1

MC3374

MAXIMUM RATINGS

Supply Voltage 18 5.0 Vdc
RF Input Signal 31 1.0 Vrms
Audio Buffer Input 21 1.0 Vrms
Data Buffer Input 26 1.0 Vrms
Comparator Input 13 1.0 Vrms
Junction Temperature – 150 °C
Storage Temperature – –65 to +150 °C

Device should not be operated at or outside these values. The “Recommended Operating Limits” provide
for actual device operation.

RECOMMENDED OPERATING CONDITIONS

Supply Voltage 18 1.1 to 3.0 Vdc
Receiver Enable Voltage 15 V

1.2 V Select Voltage 19 Open or V
RF Input Signal Level 31 0.001 to 100 mVrms
RF Input Frequency 31 0 to 75 MHz
Intermediate Frequency (IF) – 455 kHz
Audio Buffer Input 21 0 to 75 mVrms
Data Buffer Input 26 0 to 75 mVrms
Comparator Input 13 10 to 300 mVrms
Ambient Temperature – –10 to 70 °C

(Voltage with respect to Pins 4 and 10; TA = 25°C.)

Rating Pin Value Unit

Parameter Pin Value Unit

CC

CC

Vdc
Vdc

ELECTRICAL CHARACTERISTICS (V

Circuit of Figure 1, unless otherwise noted.)

Characteristic

OVERALL MC3374 PERFORMANCE

Drain Current – Pin 15 = VCC (Enabled)

Drain Current – Pin 15 = 0 Vdc (Disabled)

Recovered Audio (RF Input = 10 µV) 6 13 18 30 mVrms
Noise Output (RF Input = 0 mV, 300 Hz–5.0 kHz) 6 – 1.0 – mVrms
Input for –ā3.0 dB Limiting

MIXER

Mixer Input Resistance (Rp) 31 – 1.5 – kΩ
Mixer Input Capacitance (Cp) 31 – 9.0 – pF

FIRST IF AMPLIFIER

First IF Amp Voltage Gain – – 27 – dB

AUDIO BUFFER

Voltage Gain – 3.0 4.0 4.7 V/V
Input Resistance 21 – 110 – kΩ
Maximum Input for Undistorted Output (<5% THD) 21 – 64 – mVrms
Maximum Output Swing (<5% THD) 22 – 690 – mV
Output Resistance 22 – 780 – Ω

DATA BUFFER

Voltage Gain – 1.4 2.7 4.3 V/V
Input Resistance 26 – 9.8 – MΩ
Maximum Input for Undistorted Output (<5% THD) 26 – 100 – mV rms
Maximum Output Swing (<5% THD) 27 – 800 – mV
Output Resistance 27 – 690 – Ω

= 1.3 V, fo = 10.7 MHz, f

CC

= 1.0 kHz, Deviation = 3.0 kHz, TA = 25°C, Test

mod

Pin Min Typ Max Unit

5 + 18 + 24
5 + 18 + 24

31 – 0.6 – µVrms

–
–

1.6

0.5

3.0
–

mA

µA

pp

pp

2

MOTOROLA ANALOG IC DEVICE DATA

MC3374

ELECTRICAL CHARACTERISTICS (continued) (V

= 1.3 V, fo = 10.7 MHz, f

CC

= 1.0 kHz, Deviation = 3.0 kHz, T

mod

A

= 25°C, Test Circuit of Figure 1, unless otherwise noted.)

Characteristic

Pin Min Typ Max Unit

COMPARATOR

Minimum Input for Triggering (RL = 100 kΩ) 13 – 7.0 – mVrms
Maximum Input Frequency (RL = 100 kΩ) 13 – 25 – kHz
Rise Time (10–90%; RL = 100 kΩ) 14 – 5.0 – µs
Fall Time (90–10%; RL = 100 kΩ) 14 – 0.4 – µs

LOW BATTERY DETECTOR

Low Battery Trip Point 19 – 1.2 – Vdc
Low Battery Output – VCC = 0.9 V

Low Battery Output – VCC = 1.3 V

20
20

–
–

0.2

V

CC

–

Vdc

–

VOLTAGE REGULATOR

Regulated Output (see Figure 4) 17 0.95 1.07 1.15 Vdc
Source Capability 17 – – 3.0 mA

Figure 1. MC3374 Pager IF Application Circuit

RF Input

50

FL1

L1

C

XRD

56 k

C

C1

C2C1

L2

C3

C4

C

10

LC1 100 100 k

C

C2

C3

B

0.1

1
2
3
4
5

Output

6
7
8

C

B

C

32 31 30 29 28 27 26 25

Mixer

MC3374

Buffer

Low
Pass
Filter

Quadrature
Demodulator

9 10111213141516

N.C. N.C.

B

2nd IF

Main

Current

Reference

Comp.

FL2

Data

Buffer

Voltage

Reference

Receiver

Enable

1st IF

Audio
Buffer

Battery

Detector

Voltage

Reference

Enable

Low

0.01

24
23
22
21
20
19
18
17

Disable

180 k

– 330

0.1 10

1.0

4.7

+

0.1

39 k

0.1

µ

F

1.0

8.2 k

8.2 k

3.3 k

0.22

R

L

3900 P

0.022

Audio
Output

NOTES:

1.FL1 and FL2 are 455 kHz ceramic bandpass filters, which should
have input and output impedances of 1.5 kΩ to 2.0 kΩ. Suggested
part numbers are MuRata CFU455X or CFW455x – the ‘X’ suffix
denotes bandwidth.

2.LC1 is a 455 kHz LC resonator. Recommended part numbers are
T oko America RMC2A6597HM or 5SVLC–0637BGT (smaller).
The evaluation board layout shown provides for use of either
resonator. Ceramic discriminator elements cannot be used with
the MC3374 due to their low input impedance. The damping
resistor value can be raised to increase the recovered audio or
lowered to increase the quadrature detector’s bandwidth and
linearity – practical limits are approximately 27 kΩ to 75 kΩ.
Typically the quadrature detector’s bandwidth should match the
low IF filter’s bandwidth.

3.The data buffer is set up as a low–pass filter with a corner
frequency of approximately 200 Hz. The audio buffer is a
bandpass filter with corner frequencies of 300 Hz and 3.0 kHz.
The audio amplifier provides bass suppression.

MOTOROLA ANALOG IC DEVICE DATA

Data Output

V

CC

V

EE

4.CC1 and CC3 are RF coupling capacitors and should have ≤ 20 Ω
impedance at the desired input and oscillator frequencies.

5.CC2 provides “light coupling” of the oscillator signal into the mixer,
and should have a 3.0 kΩ to 5.0 kΩ impedance at the desired
local oscillator frequency.

6.Capacitors labelled CB are bypass capacitors and should have
20 Ω impedance at the desired RF and local oscillator frequencies.

7.The network of L1, C1 and C2 provides impedance matching of
the mixer input (nominally 3.0 kΩ shunted by 9.0 pF) to 50 Ω at the
desired RF/IF input frequency. This will allow for bench testing of
the receiver from typical RF signal generators or radio service
monitors, but additional or different matching will be required to
maximize receiver sensitivity when used in conjunction with an
antenna, RF preamplifier or mixer.

3