TK10931V - ..:: CONRAD-FORUM. · PDF file2001-01-28 · voltage will be set to 2.7...

January 2001 TOKO, Inc.

TK10931V

Amateur Radios CB Radios Utility Radios Scanner Receivers

TK10931V

NARROW BAND FM/AM IF SYSTEM

Simultaneous Operation (AM Section, FM Section) AM Section with ON/OFF Control Input AGC Amplifier Control Input AGC Amplifier Output High-speed FM Limiter Amplifier (Up to 11 MHz) RF AGC Output (for External RF Amplifier) Built-in Noise Squelch Circuit (Noise Amplifier,

Rectifier, Comparator) Wide Range Voltage Operation (2.5 V to 8.5 V) Very Small Package (TSSOP-24)

BLOCK DIAGRAM

The TK10931V is an IF system IC designed for communi-cations equipment. The TK10931V contains the followingfunctions:Oscillator MixerFM IF Limiter Quadrature DetectorAM AGC Amplifier Squelch Noise AmplifierAM Detector Squelch RectifierRSSI Output RF AGC OutputSquelch Comparator

The TK10931V is suited for Amateur radios, CB radios, andWide-Band receivers.

The TK10931V is available in the very small TSSOP-24surface mount package.

FEATURES APPLICATIONS

DESCRIPTION

RF INPUT

GND

COMP OUTPUT

COMP INPUT

NOISE AMP OUTPUT

NOISE AMP INPUT

AM AGC INPUT

OSC(B)

OSC(E)

MIX OUTPUT

VCC

AM IF INPUT

DECOUPLING

FM IF INPUT

DECOUPLING

DECOUPLING

LIM OUTPUT

QUAD INPUT

FM DET OUTPUT

AGC AMP OUTPUT

RF AGC OUTPUT

RSSI OUTPUT

AM SW

AM DET OUT

RSSI

RF

INP

UT

GN

D

CO

MP

OU

TP

UT

CO

MP

INP

UT

NO

ISE

AM

P O

UT

PU

T

NO

ISE

AM

P IN

PU

T

AM

AG

C IN

PU

T

AG

C A

MP

OU

TP

UT

RF

AG

C O

UT

PU

T

RS

SI O

UT

PU

T

AM

SW

AM

DE

T O

UT

OS

C(B

)

OS

C(E

)

MIX

OU

TP

UT

VC

C

AM

IFIN

PU

T

DE

CO

UP

LIN

G

FM

IF IN

PU

T

DE

CO

UP

LIN

G

DE

CO

UP

LIN

G

LIM

OU

TP

UT

QU

AD

INP

UT

FM

DE

T O

UT

PU

T

OSC MIXER

AMAMP

VC

C

AGCVre

f

AMP

RECT

CO

MP

AMDET

FM DET

ORDERING INFORMATION

TAPE/REELCODETL: Tape Left

Tape/ReelCode

TK10931V


TK10931V

LOBMYS RETEMARAP SNOITIDNOCTSET NIM PYT XAM STINU

I CC tnerruCylppuSNOMA,tupnIoN 3.5 1.7 Am

FFOMA,tupnIoN 7.3 0.5 Am

GM niaGnoisrevnoCrexiM F554UFCgnisU 22 Bd

R MI ecnatsiseRtupnIrexiM tnemerusaeMCD 6.3 kΩ

NOITROPMF

DANIS DANISBd21 VEDzHk3± 11 81 µBd

V 1)TED(TUO

egatloVtuptuOnoitaludomeD1

VEDzHk3±,µBd08+ 55 08 501 smrVm

1DHT noitrotsiDcinomraHlatoT µBd08+ 0.1 0.2 %

Gf niaGreifilpmAretliFf NI R,zHk1= f k072= Ω,R NI k1= Ω 74 Bd

SH leveLhgiHlortnoCNACS V5.2tupnIhcleuqS 5.2 V

SL leveLwoLlortnoCNACS V0tupnIhcleuqS 3.0 V

SYH siseretsyHhcleuqS 76 Vm

V ISSR egatloVtuptuOISSR

tupnIoN 0.0 1.0 5.0 V

V NI µBd04+= 4.0 8.0 2.1 V

V NI µBd001+= 0.1 4.1 8.1 V

FR CGA lortnoCniaGcitamotuAFR V1=61VTUOCGAFR 26 96 67 µBd

Supply Voltage ......................................................... 10 VOperating Voltage Range ............................... 2.5 to 8.5 VPower Dissipation (Note 1) ................................. 230 mWFM Limiter Amp Input Frequency ......................... 11 MHz

ABSOLUTE MAXIMUM RATINGS

TK10931V ELECTRICAL CHARACTERISTICSTest Conditions: V

CC =

3.0 V, T

A = 25 °C, unless otherwise specified.

Note 1: Power dissipation is 230 mW in free air. Derate at 1.84 mW/°C for operation above 25 °C.Note 2: If the ambient temperature falls below -10 °C, the harmonic distortions of the AM detector output are increased; the minimum operation voltage will be set to 2.7 V.

AM AGC Amp Input Frequency ........................... 0.5 MHzMixer Input Frequency ....................................... 150 MHzStorage Temperature Range ..................... -55 to +150 °COperating Temperature Range .................... -30 to +85 °C


TK10931V

LOBMYS RETEMARAP SNOITIDNOCTSET NIM PYT XAM STINU

NOITROPMA

S ytivitisneSleveLtuptuOnehwleveLtupnI

smrVm02=61 32 µBd

V 2)TED(TUO egatloVtuptuOnoitaludomeD V,%03zHk1 NI µBd06+= 53 05 56 Vm

2DHT 2noitrotsiDcinomraHlatoT V,%03zHk1 NI µBd06+= 0.1 0.2 %

3DHT 3noitrotsiDcinomraHlatoT V,%08zHk1 NI µBd06+= 0.2 0.4 %

lov )CGA( leveLtuptuOreifilpmACGAnoitaludoMnoN

V NI µBd06+=005 Vm P-P

V FFO egatloVFFOMA 3.0- 3.0 V

V NO egatloVNOMA V8.0 CC

TK10931V ELECTRICAL CHARACTERISTICS (CONT.)Test Conditions: V

CC =

3.0 V, T

A = 25 °C, unless otherwise specified.


TK10931V

TEST CIRCUIT

~51 Ω 10.7 MHz

VCC

0.01 µF

+

10 µF51 kΩ

+1 µF

+1 µF

270 kΩ

1 kΩ +

10 µF

20 kΩ 20 kΩ

10kΩ

0.1 µF

10kΩ

0.1 µF

VCC8.2 kΩ

0.01 µF

10 kΩ

0.01 µF

7BRE-7437Z

0.1 µF

30 kΩ

10 pF

0.1 µF0.1 µF10.245 MHz

33 pF

120 pF

CFU455F

0.1 µF0.1 µF

+

VCC

0.01 µF 10 µF

30 kΩ

~

OSC MIXER

CO

MP

ECT +-

AMP

Vre

f

AGCAM DET

RSSI


TK10931V

TYPICAL PERFORMANCE CHARACTERISTICSV

OU

T (

dB

m)

OUTPUT VOLTAGE vs.INPUT VOLTAGE

VIN (dBµ)

-100 0 20 40 60 80 100 120

-60

-40

-20

-80

0

DesiredfIN = 10.700 MHz

3rd Order IntermodfIN1 = 10.699 MHzfIN2 = 10.698 MHZ

VO

UT

(d

Bm

)

OUTPUT VOLTAGE vs.OSCILLATING VOLTAGE

VOSC (dBµ)

-100 -40 -30 -20 -10 0 10 20

-80

-70

-90

-60

S+

N+

D,N

(d

Bm

)

-60

S+N+D, N, and THDvs. INPUT VOLTAGE

VIN (dBµ)

-100-20 0 20 40 60 80 100 120

-20

TH

D (

%)

-80

-40

0

0

4

8

12

16

20

S+N+D

NTHD

VO

UT

(m

Vrm

s)

10

1000

∆f (kHz)

0.1-15 -10 -5 0 5 10 15

TH

D (

%)

1

100

0.1

10

THD 1

100

1000

VOUT

FM DETUNE CHARACTERISTICS

VD

C (

V)

1.0

2.5

∆f (kHz)

0.0-60 -40 -20 0 20 40 60

0.5

2.0

1.5

S-CURVE

VO

UT

(d

Bm

)

-80

-40

OUTPUT VOLTAGE vs.INPUT FREQUENCY (fIF - 455 kHz)

fIN (MHz)

-120 1 10 100 1000

-100

-60 VCC = 9.0 VVCC = 3.0 VVCC = 2.3 V


TK10931V

TYPICAL PERFORMANCE CHARACTERISTICS (CONT.)

VO

UT

(d

Bm

)

0

fIN (kHz)

-80 1 10 100 1000

-60

-20

-40

FM OUTPUT VOLTAGE vs.INPUT FREQUENCY

Rd = 30 kΩDEV = ±3 kHz

Rd = 30 kΩ // 1 kΩDEV = ±15 kHz

S+

N+

D,N

(d

Bm

)

-60

AM DETECTOR OUTPUT vs.MIXER INPUT

VIN (dBµ)

-100-20 0 20 40 60 80 100 120

-20

TH

D (

%)

-80

-40

0

0

4

8

12

16

20

S+N+D

N

THD1

THD2

VO

UT

(m

Vrm

s)

10

1000

∆f (kHz)

0.1-20 -10 0 10 20

TH

D (

%)

1

100

0.1

10

1

100

1000

VOUT

THD

AM DEMODULATION DETUNING

VO

UT

(d

Bm

)

AGC AMP OUTPUT VOLTAGEvs. INPUT VOLTAGE

VIN (dBµ)

-100-20 0 20 40 60 80 100 120

-60

-40

-20

-80

0

CARRIER

DISTORTION

VO

UT

(V

)

RSSI OUTPUT VOLTAGE vs.INPUT VOLTAGE

VIN (dBµ)

0.0-20 0 20 40 60 80 100 120

0.8

1.2

1.6

0.4

2.0

VCC = 9.0 V

VCC = 3.0 V

VCC = 2.3 V

10 kΩ

7BRE-7437Z

0.1 µF

30 kΩ

10 pF0.1 µF0.1 µF0.1 µF

RF AGC

RSSI FM DET

~V

VCC

+

4.7 µH

10 µF

FMAMP

0.01µF

S-CURVE MEASUREMENT CIRCUIT (fIN = 455 kHz)


TK10931V


VO

UT

(d

BV

)

-20

10

RECTIFIER CIRCUITFREQUENCY RESPONSE

fIN (kHz)

-50 1 10 100 1000

-30

0

-40

-10

VO

UT

(V

)

RSSI OUTPUT VOLTAGE vs.INPUT VOLTAGE

VIN (dBµ)

0.0-20 0 20 40 60 80 100 120

0.8

1.2

1.6

0.4

2.0-40 °C+25 °C+85 °C

VO

UT

(V

)

RF AGC OUTPUT VOLTAGE vs.INPUT VOLTAGE

VIN (dBµ)

0.0-20 0 20 40 60 80 100 120

0.8

1.2

1.6

0.4

2.0VCC = 2.3 VVCC = 3.0 VVCC = 9.0 V

VO

UT

(V

)

RF AGC OUTPUT VOLTAGE vs.INPUT VOLTAGE

VIN (dBµ)

0.0-20 0 20 40 60 80 100 120

0.8

1.2

1.6

0.4

2.0

-40 °C+25 °C+85 °C

VO

UT

(V

)RECTIFIER OUTPUT VOLTAGE vs.

MIXER INPUT LEVEL

VIN (dBµ)

0.0-20 0 20 40 60 80 100 120

0.8

1.2

1.6

0.4

2.0

VCC = 2.4 VVCC = 3.0 VVCC = 9.0 V

++VrefVref

VCC

+1 µF 51 kΩ

TK10931V

1 kΩ 8.2 kΩ

AF OUT

0.01 µF330 pF

20 kΩ

100 pF 100 pF20 kΩ

RECT

30 kΩ

MIXER INPUT FREQUENCY = 10.7 MHzMOD DEV = ±3 kHzfIN = 1 kHz

RECTIFIER VOLTAGE MEASUREMENT CIRCUIT


TK10931V


+

Vref

+

TK10931V

RECT

+

20 kΩ 20 kΩ1 µF

51 kΩ 1 µF

RECTIFIER FREQUENCY MEASUREMENT CIRCUIT

I CC

(m

A)

SUPPLY CURRENT vs.SUPPLY VOLTAGE

VCC (V)

0 0 2 4 6 8 10

6

8

2

10

4

AM ON

AM OFF

VH

YS

, CO

MP

IN (

V)

VHYS, COMP IN (V) vs.

SUPPLY VOLTAGE

VCC (V)

0 0 2 4 6 8 10

0.6

0.8

0.2

1.4

0.4

VH

1.0

1.2

VL

VHYS

VHYS

VH VL

VO

UT

(m

V)

80

FM OUTPUT VOLTAGE, 12 dB SINADvs. SUPPLY VOLTAGE

VCC (V)

0 0 2 4 6 8 10

160

12 d

B S

INA

D (

dB

µ)

40

120

200

0

20

40

60

80

100

VOUT DEV = ±3 kHz

12 dB SINAD

TH

D (

%)

0.8

TOTAL HARMONIC DISTORTION vs.SUPPLY VOLTAGE

VCC (V)

0.0 0 2 4 6 8 10

1.6

0.4

1.2

2.0

THD (%)

VO

UT

(m

V)

80

AM OUTPUT VOLTAGE vs.SUPPLY VOLTAGE

VCC (V)

0 0 2 4 6 8 10

160

20 m

Vrm

s V

OU

T (

dB

µ)

40

120

200

0

20

40

60

80

100

VOUT DEV = 80%

20 mVrms VOUT

VOUT DEV = 30%


TK10931V


RSSI, RFAGC TRANSIENT RESPONSE

(RISE)

Rise Time: 12.5 µsec

5 µsec/div

493.4 ms

> 20 mV

• CL = 560 pF

(FALL)

Fall Time: 16.0 µsec

5 µsec/div

986.0 ms

> 20 mV

100%

90%

10%0%

A2 3.90 V A2 3.90 VDLY DLY

TH

D (

%)

0.8

TOTAL HARMONIC DISTORTION vs.SUPPLY VOLTAGE

VCC (V)

0.0 0 2 4 6 8 10

1.6

0.4

1.2

2.0

THD (DEV = 30%)

THD (DEV = 80%)

RSSI ON/OFF

10 kΩ CL

RSSI Output

RSSI

10 kΩ CL

RFAGC Output

RFAGC

RSSI OUTPUT VOLTAGE TRANSIENT RESPONSE (MIXER INPUT ON/OFF)

PIN 15 AND 16EXTERNAL COMPONENTS


TK10931V

RSSI ON/OFF (CONT)

(RISE)

Rise Time: 2.0 msec

1msec/div

28.20 ms

> 20 mV

• CL = 0.1 µF

(FALL)

Fall Time: 2.2 msec

38.19 ms

> 20 mV

100%

90%

10%0%

1msec/div

A2 3.90 V A2 3.90 VDLY DLY

(RISE)

Rise Time: 1.1 msec

0.5msec/div

18.52 ms

> .2 V=

• CL = 560 pF

(FALL)


29.86 ms

> .2 V=

100%

90%

10%0%

0.1µsec/div

DELAY DELAY

(RISE)

Rise Time: 2.6 msec

1 msec/div

15.73 ms

> .2 V=

• CL = 0.1 µF

(FALL)

Fall Time: 1.6 msec

26.28 ms

> .2 mV=

100%

90%

10%0%

1msec/div

DELAY DELAY

RSSI OUTPUT VOLTAGE TRANSIENT RESPONSE (POWER SUPPLY VOLTAGE ON/OFF)


TK10931V

RFAGC ON/OFF

(RISE)

Rise Time: 2.2 msec

1 msec/div

7.955 ms

> 20 mV

• CL = 0.1 µF

(FALL)

Fall Time: 2.2 msec

1 msec/div

38.21 ms

> 20 mV

100%

90%

10%0%

A2 3.90 V A2 3.90 VDLY DLY

(RISE)


5 µsec/div

494.8 ms

> 20 mV

• CL = 560 pF

(FALL)


5 µsec/div

990.4 ms

> 20 mV

100%

90%

10%0%

A2 3.90 V A2 3.90 VDLY DLY

(RISE)


5 µsec/div

19.93 ms

> .2 V=

• CL = 560 pF

(FALL)


10 µsec/div

29.86 ms

> .2 V=

100%

90%

10%0%

DELAY DELAY

RFAGC OUTPUT VOLTAGE TRANSIENT RESPONSE (MIXER INPUT ON/OFF)

RFAGC OUTPUT VOLTAGE TRANSIENT RESPONSE (POWER SUPPLY VOLTAGE ON/OFF)


TK10931V

RFAGC ON/OFF (CONT)

(RISE)

Rise Time: 2.2 msec

1 msec/div

17.15 ms

> .2 V=

• CL = 0.1 µF

(FALL)

Fall Time: 1.6 msec

1 msec/div

27.06 ms

> .2 V=

100%

90%

10%0%

DELAY DELAY


TK10931V

.ONNIP LOBMYS EGATLOV TIUCRICTNELAVIUQELANRETNI NOITPIRCSED

12

)B(CSO)E(CSO

V89.2V2.2

otdesuebnac2dna1sniP.rotallicsoepytsttiplocadliubgnitareporewollof-rettimeehT

ybdesaercniebnactnerrucrotsiserlanretxenagnitcennoc

nehwDNGdna2niPneewtebehttcejnI.yvaehsidaoleht

yb1niPotnilangisgnitallicsoniPhtiwgnilpuocedeviticapac

lanretxenanehwNEPO2ehtfodaetsnidesusirotallicso

.rotallicsolanretni

3 TUPTUOXIM V6.1 .lanimreTtuptuOrexiMsiecnadepmituptuoehT

k8.1yletamixorppa Ω.

4 V CC V0.3 lanimreTylppuSrewoP

5 TUPNIFIMA V9.1 tupnIlangiSreifilpmACGAMAlanimreT

6 GNILPUOCED V2.1 gnilpuoceDreifilpmACGAMAlanimreT

789

TUPNIFIMFGNILPUOCEDGNILPUOCED

V0.2V0.2V0.2

retimiLFIMFehtsi7niP.lanimreTtupnIlangiSreifilpmA

siecnadepmitupniehTk8.1yletamixorppa .

MFehtera9dna8sniPgnilpuoceDreifilpmAretimiL

.slanimreT

PIN FUNCTION DESCRIPTION

VCC

3.9 k

10 k

3 pF

150 µA

VCC

1.8 k260 µA

VCC

10 k

VCC

25 µA

VCC

80 µA1.8 k


TK10931V

PIN FUNCTION DESCRIPTION (CONT.)


01 TUPTUOMIL V0.2 langiSreifilpmAretimiLMF.lanimreTtuptuO

esahpehtotstcennocnipsihT.tiucricretfihs

11 TUPNIDAUQ V0.3 gnitcennoCretfihSesahPehTlanimreT

21 TUPTUOTEDMF V3.1 tuptuOlangiSdetceteDMFlanimreT

31 TEDMA V3.1 tuptuOlangiSdetceteDMAlanimreT

41 WSMA FFO/NOreifilpmACGAMA.lanimreTlortnoC

rotceteDdna,CGA,FIMAehTetatsevitcaehtnierastiucric

otpudellupsi41niPnehwV CC .

rotceteDdna,CGA,FIMAehTetatsybdnatsehtnierastiucric

otnwoddellupsi41niPnehw.DNG

51 TUPTUOISSR lanimreTtuptuOlangiSISSR

VCC

160 µA

VCC

40 µA

VCC

120 µA

20 pF

100 k

100 k

VCC

90 µA

51 k

VCC


TK10931V



61 TUPTUOCGAFR tuptuOlangiSCGAFRlanimreT

71 TUPTUOPMACGA V1.1 langiSreifilpmACGAMA.lanimreTtuptuO

sitnerructuptuomumixaM.Am1otpu

81 TUPNICGAMA niaGreifilpmACGAMAlanimreTlortnoC

91 TUPNIPMAESION V5.1 tupnIlangiSreifilpmAesioNhcleuqSehtroflanimreT

02 PMAESIONTUPTUO

V5.1 langiSreifilpmAesioNtiucriCreifitceRdnatuptuOehtroflanimreTtupnIlangiS

hcleuqS

12 TUPNIPMOC langiStiucriCreifitceRrotarapmoCdnatuptuOroflanimreTtupnIlangiS

hcleuqS

VCC

VCC

100 k

100 k

VCC

20 µA

VCC

VCC/2

20 µA

VCC

51 k

VCC

20 µA


TK10931V



22 TUPTUOPMOC tuptuOlangiSrotarapmoChcleuqSroflanimreT

32 DNG V0 lanimreTDNG

42 TUPNIFR V0.1 lanimreTtupnIlangiSrexiMVCC

260 µA30 pF3.6 k

3.6 k

1 V

VCC

100 k

5 k

20 µA


TK10931V

CIRCUIT DESCRIPTION

The TK10931V has various functions that include a mixer up to 150 MHz, and independent AM IF and FM IF stages. Thismakes the TK10931V suitable for a communications receiver as described in the following.The FM-IF stage is always in operation, but the AM-IF stage is available with an ON/OFF function.The AM-IF signal is available from a buffered output in front of the AM detector. Its output signal is available for an externaldetector such as a product detector.In addition, the RF AGC output for an external RF stage and a built-in rectifier for noise squelch are available. As a result,the application circuit can be simple.The RSSI output is implemented with wide dynamic range and excellent temperature characteristics.The Mixer is implemented with wide dynamic range in spite of high gain.

(1) Mixer, OscillatorThe Mixer consists of a Gilbert multiplier, Oscillator, and IF amplifier.The Mixer circuit is optimized, resulting in a wide dynamic range in spite of a high transfer gain (22 dB).The Noise Figure is approximately 10 dB under input impedance matching conditions.The frequency response as a function of input impedance is shown in Figure 1.

ycneuqerF)zHM(

ecnadepmItupnI

(pR ΩΩΩΩΩ) )fp(pC

01 8783 09.3

02 2353 05.3

03 3982 42.3

05 9882 60.3

07 0262 01.3

001 8542 21.3

051 8212 40.3

FIGURE 1

The built-in oscillator circuit consists of a general Colpitts type oscillator with the collector grounded. The operating currentof the oscillator is 100 µA.As shown later, operating above tens of MHz is possible by increaing the Gm of the oscillator with an externally connectedresistor.Figure 2 illustrates general Colpitts type oscillators. Various resonators my be used, for instance, L/C, crystal, ceramic,SAW, and others.

50

-j10

-j25

-j50 -j100 -j250

100 250f = 10 MHz 30 MHz 50 MHz 100 MHz 150 MHz

S11Mixer Input


TK10931V

CIRCUIT DESCRIPTION (CONT.)

FIGURE 2: EXAMPLES FOR COLPITTS TYPE OSCILLATOR

External InjectionIf an external oscillator is used instead of the internal oscillator, inject the oscillating signal into Pin 1 by a capacitorconnection. Pin 2 must be opened, as shown in Figure 3.In this case, the multiplier sees the oscillator being operated as an emitter follower.

FIGURE 3: EXAMPLE FOR EXTERNAL OSCILLATOR

Overtone OscillationWhen operating an overtone oscillation above 30 MHz using a crystal resonator, design using the circuit shown in Figure5 to reduce the fundamental mode.When the operation frequency is higher, it is possible that the Gm of the oscillator may be insufficient and the oscillatingamplitude will be down. This can be improved by connecting an external resistor between Pin 2 and GND to increase theoperating current.

VCC VCC VCC

Crystal Resonator LC Resonator SAW Resonator

VCC

Pin 2 must be open


TK10931V


FIGURE 4: EXAMPLE FOR OVERTONE OSCILLATION

FIGURE 5

The constants of the circuit in the dotted line of Figure 4establish that the condition of oscillation is met for the 3rdovertone frequency only.Figure 5 shows the characteristics of the impedance of thetwo terminals versus frequency of this circuit.The condition of oscillation is the capacitance at theovertone frequency and the inductance at near-fundamen-tal frequency. Therefore, when it is established that thefundamental frequency is included between FA and FB andthat the overtone frequency is above FB, the condition of 3times overtone is:

F(osc) > FA 3 x F(osc) > FB,

1

2π LC3FA = FB = FA 1 + C2

C3

F(osc) is the fundamental frequency of the crystalresonator.3 x F(osc) is the 3rd overtone frequency of the crystalresonator.

Moreover, it is established that the series value of theequivalent capacitance of the circuit is in the dotted line ofFigure 4 and capacitance C1 is the load capacitance of thecrystal resonator.When the operating current of the oscillator is insufficient,increase Gm of the oscillator by the external resistor RE. Inthis case, the increased operating current (Ie) of theoscillator is calculated by the following:

(2) RF AGC OutputFor manufacturers with equipment requiring external RFamplifiers, etc., the RF-AGC output terminal is readilyavailable. Because this AGC output is picked out from thefirst stage of the FM-IF portion, the AGC output is notaffected by the AM switch when stopping the AM-IFoperation. Therefore, when receiving an FM signal, itsoutput contributes to improving strong input characteris-tics.

Its output is implemented as a current output from thecollector of the PNP-transistor. Therefore, its current isconverted into a voltage with an external resistor.A composite example is shown as Figure 6. A receivercircuit example in CB radios is shown at “CB RadioApplication” of the Application Information section. Theexample in Figure 6 controls the gain by changing the biasvoltage of the RF-AMP with the output of transistor QA1that is driven with the RF-AGC output of Pin 16.

FIGURE 6: EXAMPLE FOR EXTERNAL AGCAMPLIFIER

VCC

(V) - 0.7Ie(mA) =

RE(KΩ)

VCC

200 µA

C2

LC3

RE

X'talC1

Frequency

FA FB+j

-j

Rea

ctan

ce

VCC

VCC

QA1

RF-AMP

VCC

AGC Line


TK10931V


FIGURE 7

FIGURE 8: RSSI OUTPUT EQUIVALENT CIRCUIT

(4) FM DetectorThe FM detector is included in the Quadrature FM detectorusing a Gilbert multiplier. The phase shifter is connectedbetween Pin 10 (IF limiter output) and Pin 11 (detectorinput), with any available phase shifter. A phase shifter canbe used such as the LC resonance circuit, the ceramicdiscriminator, and the delay line. Figure 11 shows theinternal equivalent circuit of the detector. The signal fromthe phase shifter is applied to the multiplier (in the dottedline) through emitter-follower stage QA. Note that Pin 11must have the bias voltage impressed from an externalsource, because Pin 11 is connected with the base of QAonly. Because the base of QB of the opposite side isconnected with the supply voltage, Pin 11 has to be biasedwith the equivalent voltage. Using an LC resonance circuitis not a problem (see Figure 10), but attention must be paidwhen using a ceramic discriminator. If the base voltagesare different, the DC voltage of the multiplier does notbalance. This alters the DC zero point or worsens thedistortion of the demodulation output. The Pin 11 inputlevel should be saturated at the multiplier, if this level islower, it is easy to disperse the detector output. Therefore,to be in stable operation, the Pin 16 input level should behigher than 100 mVP-P. Figure 10 shows examples ofphase shifters.

FIGURE 9: FM DETECTOR EQUIVALENT CIRCUIT

(3) FM-IF Limiter Amplifier, RSSIThe IF limiter amplifier is composed of 6 differential gainstages. The total gain of the IF limiter amplifier is 80 dB at455 kHz. The output signal of the IF limiter amplifier isprovided at Pin 10 through the emitter-follower outputstage. The IF limiter amplifier output level is 0.5 VP-P. Theoperating current of the emitter-follower at the IF limiteramplifier is 200 µA.If the capacitive load is heavy, the negative half cycle of theoutput waveform may be distorted. This can be improvedby connecting an external resistor between Pin 10 andGND to increase the operating current. The increasedoperating current by an external resistor is calculated asfollows (see Figure 7):

The increased operating current Ie(mA) = (VCC - 1.0)/Re(kΩ)

The RSSI output is a current output. It is converted to avoltage by an external resistor connected between Pin 15and GND. The time constant of the RSSI output isdetermined by the product of the external convertingresistance and the parallel capacitance. When the timeconstant is longer, the RSSI output response is slower.Determine the external resistance and capacitance by theapplication. The slope of the RSSI curve characteristicscan be changed by changing the external resistance. Inthis case, the maximum range of converted RSSI outputvoltage is from GND level to about VCC-0.2 V (the supplyvoltage minus the collector saturation voltage of the outputtransistor). In addition, the temperature characteristic ofthe RSSI output voltage can be changed by changing thetemperature characteristic of the external resistor.Normally, the temperature characteristic of the RSSIoutput voltage is very stable when using a carbon resistoror metal film resistor with a temperature characteristic of 0to 200 ppm/°C.

VCC

RSSI OUT

Current Output

I-V Converting Resistor

VCC VCC

QB

VCC

VCC

200 µA

100

Ie

Re

IF OUT

The emitter-follower operatingcurrent can be increased byexternal resistor Re when thecapacitive load is heavy andthe waveform distortion will bereduced.


TK10931V


FIGURE 10: EXAMPLES OF PHASE SHIFTERS

(5) AM IF BlockThe AM IF block is shown in Figure 11. This block is composed of three blocks: the IF AGC amplifier, the AM IF output,and the AM detector. The AGC range is approximately 50 dB.

FIGURE 11: AM IF EQUIVALENT CIRCUIT

The AM IF Input ImpedanceThe AM IF input terminal (Pin 5) is independent of the FM IF input terminal (Pin 7). Respectively different filters for the FMIF and AM IF can be used. The input impedance of the AM IF input terminal (10kΩ) is higher than the FM IF input terminal(1.5 kΩ). Although the AM IF input terminal and the FM IF input terminal are conncected in parallel AC wise, when usingcommon IF filters, it is only necessary to use the FM IF input impedance to determine the termination impedence of thecommon IF filter.

AM IF-AGCPin 18 is the IF AGC control input terminal. Usually this terminal is connected with the AM detector output terminal (Pin12) through the ripple filter composed of R1 and C3. The time constant (T = R1 x C3) for the ripple filter is generally selectedto be 5 to 10 times larger than the lowest cycle of the AM modulation element. Pin 18 can also be controlled by an externalDC source instead of the AM detector output signal. Pin 6 is the decoupling capacitor for the AM IF bias circuit.

VCCVCC

VCC

DelayLine

LC Resonance Circuit Ceramic Discriminator Delay Line

Rz is the characteristic impedance

RzRz

R1

C1

R3 C5

AMIF-OUT

VCC DET

R2C4

AMDET-OUT

AMIF-AGC

IF-INPUTC2

C3

AGCAMP


TK10931V


AM IF-OutputThe output from Pin 17 is done through a buffer in front ofthe AM detector for an AM IF signal that is a fixed amplitudeoutput. Therefore, it is possible to do various applications.This output is an emitter-follower type; the operatingcurrent is determined by the resistor connected betweenthe output terminal (Pin 17) and GND. Because the DCvoltage at Pin 17 is set up as 1/2 the supply voltage, theoperating current can be computed as follows:

Ie = VCC/2Re

With 22 kΩ (standard value), the operating current is 70 µAat VCC = 3 V. Connecting a heavy load increases distortionof the minum half cycle side; decrease the resistance toincrease the operating current.

FIGURE 12: AM IF OUTPUT EQUIVALENT CIRCUIT

FIGURE 13: NOISE SQUELCH EQUIVALENTCIRCUIT

FIGURE 14: FULL-WAVE RECTIFIER EQUIVALENTCIRCUIT

(6) Noise Squelch CircuitThis product is equipped with built-in noise squelchcircuitry. It is composed of the Filter amplifier, Full-waveRectifier circuit, and the Comparator. Figure 13 illustratesthe Noise Squelch Equivalent Circuit. Figure 14 illustratesthe Full-wave Rectifier Circuit.

First, the FM detector output is amplified and the noiseelement is selected by the Band-Pass Filter that iscomposed with the built-in amplifier. The noise element isrectifed by the built-in full-wave recitifier, resulting in acurrent output from Pin 21. The current output is filteredand converted to a voltage with resistor R4 and capacitorC3 connected between Pin 21 and GND. The rectifiedvoltage is compared with the built-in reference voltage.The comparator output is provided at Pin 22. Because thecomparator output is an open collector output, a pull-upresistor is required. To prevent chatter at the output, thecomparator has hysteresis of approximately 70 mV.

The Band-Pass Filter is comprised of the built-in filteramplifier for selective noise amplification. Its circuit is thegeneral Sallen-Key type as shown in Figure 13. Theconstants can be computed as follows.

That isC1 = C2 = CF0: Center frequency for BPFQ: Q for BPFAv: Gain for BPF center frequency

The rectifier circuit, shown in Figure 14, is implementedwith a current output as mentioned previously. Therectification voltage value can be modified by changing thevalue of the converting resistor R4. The maximum valuefor its voltage, determined by the power supply voltage, isup to VCC-0.2 V. Since the threshold voltage of the built-incomparator is fixed at 0.7 V, it is possible to adjust thesquelch sensitivity by changing the value of R4. In actual-ity, in order to absorb the deviation for the whole product,the use of a trimmen resistor is recommended. Pick up thenoise signal for the detector before the de-emphasis cir-cuit.

VCC

AM IFOUT

VCC/2Ie Re

R2

VCC

+

~0.7 V

+

R1

C2 C1

R3C3R4

STATUS

VCC/2

R5

C3R4

VCC

21


TK10931V

CIRCUIT DESCRIPTION (CONT.)(7) AM-ON/OFF CircuitThis IC provides an ON/OFF function for the AM block.Because this was necessary for the stand-by state for theAM block, it can be used as a power-save operation. Theinput part equivalent circuit is shown in Figure 15.

By directly controlling the transisor-base as shown in theequivalent circuit, the AM portion ON/OFF input control ispossible below a very small current of 50 µA. RegardingPin 14, the AM portion is in operation at 2 V and above; itis in non-operation at 0.2 V and below. In non-operation,the consumption current is down to approximately 2.4 mA.The circuits that can be non-operational in AM OFF areshown as follows.

Non-operation circuits:AM IF circuit, AM IF-AGC circuit, AM detector circuit.

Always operating circuits:RF-AGC output, Noise squelch circuit, Mixer circuit, Localoscillator circuit, FM IF circuit, FM detector circuit.

FIGURE 15

(8) Attention to Pattern LayoutThis product will provide stable operation. However, whenusing this product, pay attention to the following (1-3) forstable operation because the operating frequency is high.Moreover, the standard application board of this product isshown on page 25.

1. The VCC terminal capacitor is individually grounded bythe shortest distance to a GND terminal.VCC Terminal (Pin 4) • GND Terminal (Pin 23)

2. Overall, the IF signal level is higher than other points.Also, this point is the final stage in the limiter amplifier.Therefore, this point easily provides positive feedback tothe first stage. Since feedback to the pre-stage dependson radiation, use the shortest distance etch patterns pos-sible.

Feedback through the power supply line from the cold sideof the phase shifter is common. To keep the signal level ofthe phase shifter at its highest, treatment of its cold side isvery important.

Grounding the cold side with bypass a capacitor is impor-tant. Adding a decoupling circuit that uses a CR or LC iseffective. An example is shown in Figure 16.

Avoid using high resistance values in the offset of themultiplier in the FM detector. When using under about 1kΩ, there is no effect because the inflow current in Pin 11is under several µA.

3. When the signal is returned to the mixer from thedetector, the stability is at its worst. It is ideal that theseperipheral components are provided with different sides ofa double-sided board and that the reverse side is the GNDpattern.

FIGURE 16: EXAMPLE OF STRONG DECOUPLINGAROUND THE PHASE SHIFTER

50 k

BIAS

AMON

AMOFF

VCC

47 µF

0.1 µF0.1 µF220 Ω

to 1 kΩ

January 2001 TO

KO

, Inc.

TK10931V

AP

PL

ICA

TIO

N IN

FO

RM

AT

ION

CB

Rad

io A

pp

lication

10.7 MHzVCC

0.01 µF

100 pF

330 kΩ

10 µF

10kΩ

22kΩ

0.022µF

VCC8.2 kΩ

0.01 µF

10 kΩ

0.01 µF30 kΩ

10 pF0.1 µF0.1 µF

10.245 MHz

33 pF

100 pF

CFU455E

0.1 µF

VCC

0.01 µF 47 µF

100 kΩ

OSC

MIXER

AM IF

AM DET

0.47 µF

50 k

in m

easu

rem

ent

100 pF

VrefVref

FM IF

VCC

FM DET-OUT

5.1 kΩ

4700 pF

0.1 µF

AM IF-OUT

20 kΩ

10 kΩ

0.01 µF

RSSI OUT

RF-AGC CONTROL

SQUELCHCOMP OUT

CFSK107M3

VCC

0.01 µF

4

6 VCC = 8.0 V

FM DET

VCCVCC = 8.0 V

750

0.01µF

5.1 kΩ

330

330

0.01

µF

22 kΩ

0.01

µFT2

6

4

1

2

0.01 µF

0.01 µF

330

7 pF

1st OSC37 MHz • 0dBm

1 k 0.01 µF

0.01 µF

5.1 kΩ

22 pF

1

23

4

6

RF INPUT27 MHz

T1

50

1S-1588• ~ 3

0.01 µF

15 µF 10 kΩ0.01 µF

VCC

100 kΩ 1 kΩ

100 µF 10 kΩ

Q5 Q

3

Q4

2.2 kΩ 44 kΩ

10 kΩ

1 kΩ0.1 µF

Any circuits described herein assume no mass-production.

Toko assumes no responsibility for the use of any circuits described herein, conveys no licenseor other right, and makes no representations that the circuits are free from patent infrigement.

T1 : TXXN-22160BU

T2 : TXXC-16853N

T3 : 7BRE7437Z

Q1 : 2SC585

Q2 : 2SC1675

Q3, Q4, Q5 : 2SC945

AM DETOUT

0.01 µF

0.01 µF

0.1 µF

T3

10 k

330

560

Q1


TK10931V

APPLICATION BOARD LAYOUTS


TK10931V

Marking Information

Marking

TK10931V 10931

TSSOP-24

PACKAGE OUTLINE

Printed in the USA© 1999 Toko, Inc.All Rights Reserved

TOKO AMERICA REGIONAL OFFICES

Toko America, Inc. Headquarters1250 Feehanville Drive, Mount Prospect, Illinois 60056Tel: (847) 297-0070 Fax: (847) 699-7864

Western Regional OfficeToko America, Inc.2480 North First Street , Suite 260San Jose, CA 95131Tel: (408) 432-8281Fax: (408) 943-9790

Midwest Regional OfficeToko America, Inc.1250 Feehanville DriveMount Prospect, IL 60056Tel: (847) 297-0070Fax: (847) 699-7864

IC-231-TK110310798O0.0K

Visit our Internet site at http://www.tokoam.com

Semiconductor Technical SupportToko Design Center4755 Forge RoadColorado Springs, CO 80907Tel: (719) 528-2200Fax: (719) 528-2375

The information furnished by TOKO, Inc. is believed to be accurate and reliable. However, TOKO reserves the right to make changes or improvements in the design, specification or manufacture of itsproducts without further notice. TOKO does not assume any liability arising from the application or use of any product or circuit described herein, nor for any infringements of patents or other rights of thirdparties which may result from the use of its products. No license is granted by implication or otherwise under any patent or patent rights of TOKO, Inc.

AAAAA

e

Lot. No.

Marking

4.4

7.8

0.25

0.65

0~

0.1

5

1.2

max

0.9

+0.15-0.05

6.4

0.1

5

+0.1

5-0

.05

0.50 0~

10

Recommended Mount Pad

0.65

4.8

1.0

0.35

0.1

0.12 M

e

Dimensions are shown in millimetersTolerance: x.x = ± 0.2 mm (unless otherwise specified)

24 13

1 12

YYY

0.3+

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