470MHz INPUT MIXER AND 455kHz FM IF DEMODULATOR IC

Transcription

1 47MHz INPUT MIXER AND 455kHz FM IF DEMODULATOR IC GENERAL DESCRIPTION PACKAGE LINE The NJM2592 is a wideoperating voltage, lowcurrent FM IF demodulator IC with 455kHz(standard) IF frequency. It includes an oscillator, mixer, limiting amplifier, quadrature detector, active filter, and FSK comparator. The NJM2592 also has a circuit and comparator for carrier sense. NJM2592V FEATURES Wide Operating Voltage 1.8V to 9.V Low Operating Current 2.2mA type. at V =2.V, external local oscillator input Maximum Mixer Input Signal Frequency 47MHz (reference value) Level dbm Mixer Input Resistance 5Ω IF Frequency 455kHz (standard) Conventional Quadrature Detector External Phaseshifting Capacitor External Discriminator or LC Resonant Circuit Comparator with OpenCollector Output Quick Charge/Discharge Circuit for FSK Reference Voltage Bipolar Technology Package Outline SSOP2 BLOCK DIAGRAM MIX IN GND SENSE LEVEL CARRIER SENSE FSK SW LPF LPF IN AF OSC MIXER BUFFER COMP FSK COMP IF AMP FILTER AMP OSC (B) OSC (E) MIX V IF IN DEC FSK VREF1 FSK VREF2 IF QUAD IN QUAD DET Ver

2 ABSOLUTE MAXIMUM RATINGS (Ta=25 C) PARAMETER SYMBOL RATINGS UNIT Supply Voltage V 1. V Power Dissipation P d 3 mw Mixer Input Signal Level VmixMAX dbm Operating Temperature T o p r 4 to 85 C Storage Temperature T s t g 4 to 125 C RECOMMENDED OPERATING CONDITION (Ta=25 C) PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT Supply Voltage V V ELECTRICAL CHARACTERISTICS (Ta=25 C, V =2.V, fmix=43mhz, flo= mhz, fif=455khz, fmod=6hz, fdev=±4khz, unless otherwise noted) PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT Current Consumption I c c q No signal ma Mixer Conversion Gain G m i x VinMIX=6dBuVEMF, Measured at Pin3, without IF filter, terminated with 2kΩ db Mixer 3 rd Order Intercept IP3 95 dbuv Mixer Input Resistance R i n M (5) Ω Mixer Input Capacitance C i n M (2.) pf Mixer Output Resistance R o M 2. kω Signal to Noise Ratio 1 S / N 1 Signal to Noise Ratio 2 S / N 2 Signal to Noise Ratio 3 S / N 3 Mixer input VinMIX=6dBuVEMF IF input VinIF=6dBuVEMF IF input VinIF=25dBuVEMF 6 db 6 db 3 db 3dB Limiting Sensitivity V i n ( l i m ) IF input 22 dbuvemf AM Rejection Ratio A M R IF input, AM=3% VinIF=6dBuVEMF 5 db IF Amplifier Input Resistance R i n I F 2. kω Output Voltage V r s s i The values shown in parenthesis are reference values. IF input VinIF=4dBuVEMF (.3).45 (.65) V 2 Ver.21839

3 PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT Demodulated Output Level Duty Ratio of Wave Shaped Output Quick Charge/Discharge Current High Level Leak Current of CARRIER SENSE Terminal Low Level Voltage of CARRIER SENSE Terminal Bias Current of SENSE LEVEL Terminal High Level Leak Current of FSK Terminal Low Level Voltage of FSK Terminal V o d DR Ich The values shown in parenthesis are reference values. IF input VinIF =6dBuVEMF IF Input VinIF=6dBuVEMF FSK REF=GND LPF=.4V mvrms % ua IcryH V CARRIER SENSE =V (.) ua VcryL I CARRIER SENSE =1uA.1.4 V I l e v e l V CARRIER SENSE =.8V (.) ua I f s k H V FSK =V (.) ua V f s k L I FSK =1uA.1.4 db Ver

4 TEST CIRCUIT This test circuit allows the measurement of all parameters described in ELECTRICAL CHARACTERISTICS. This test circuit includes some electrical switches that should be in the suitable position for the measurement of each parameter. Circuit diagram CARRIER FSK SENSE 1p 43MHz 1u SWITCH V V V 1p 1k Hi 1k Lo.1u 68k 68k 68k 56p 33p OSC MIXER BUFFER MHz COMP FSK COMP 455kHz FILTER AMP p 1p V.1u 1u.1u 51 1u IF FILTER B A IF SW IF AMP 51 22p (2) 3.3k QUAD DET 1u CD V External components C D : Ceramic Discriminator, 455kHz IF FILTER : Ceramic Filter, 455kHz Measurement condition Condition1 is the condition for the case of IF input : IF SW : in the A position. IF IN input signal : input frequency(fif) = 455kHz, input level(vinif)= 6dBuVEMF, modulation frequency(fmod)=6hz, deviation fdev=±4khz Condition 2 is the condition for the case of Mixer Input : IF SW : in the B position MIX IN input signal: input frequency(fmix)=43mhz, input level(vinmix)=6dbuvemf, modulation frequency(fmod)=6hz, deviation fdev=±4khz OSC(E)input signal: input frequency(fosc)= mhz, input level(vinosc)=15dbuvemf 4 Ver.21839

5 TERMINAL FUNCTION (Ta=25 C, V =2.V) Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION V 1 OSC (B) 1 2 2p 2 OSC (E) NJM2592 Base / Emitter Terminal Colpitts type oscillator is formed with an external oscillator element of crystal unit or SAW resonator. Output of an external oscillator circuit can also input to pin1 or pin2. V Mixer Output An external 455kHz ceramic filter is connected. The typical output impedance is 2kΩ. 3 MIX 1.4k 1.1V 3 4 V V 5 IF IN 5k 1.94V 1k 1k DEC 1.94V Supply Voltage IF Limiter Amplifier Input This is an input to the IF amplifier after passing through 455kHz ceramic filter. The typical input impedance is 2kΩ. IF Decoupling An external decoupling capacitor is connected to enhance stability. 7 V 7 FSK VREF1.55V FSK Reference Input This pin is an input of reference voltage for FSK comparator. An external capacitor is connected to create an average DC level of FM demodulated signal. The choice of this capacitor is dependent on the speed of data signal. A quick charge/discharge circuit offers the voltage of pin 7 comes the same voltage of pin 11 quickly. Ver

6 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION 8 FSK VREF2.55V 8 4k V FSK Reference Voltage Output This pin usually keeps open. This fixed output voltage may be available for the FSK reference voltage of wave shaping comparator by connecting to pin7. This usage is effective in shaping the data signal with continuous bits of the same polarity, and discussed in another document related to applications information. V IF Output An external phase shifting capacitor is connected between pin9 and pin1. 9 IF 1.19V 9 4uA V QUAD IN 1.99V Quadrature Detector Input An external phase shifting coil or ceramic discriminator is connected. V FM Demodulated Signal Output An external 3rd order multiple feed back filter (RC filter) is connected between pin11 and pin AF 1k.55V 11 4uA 6 Ver.21839

7 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION 12 LPF IN.55V LPF.55V V Low Pass Filter Input An external RC components forms a band pass filter between pin12 and pin13. This terminal is biased from pin 11 though an external RC filter. Low Pass Filter Output 14 SW 14 3k V Quick Charge / Discharge Control The power supply output voltage to pin 14 sets up the quick charge / discharge circuit. Hi : ON Low : OFF Instead of V, another power source can also be used within the limit of the rated supply voltage FSK V FSK Output The FSK comparator is a wave shaping circuit. A Filter Amplifier output signal is inverted and wave shaped. Instead of V, another power source can also be used within the limit of the rated supply voltage. 16 V Carrier Sense Output This pin outputs the result of comparator by comparing output level with an external input level to pin CARRIER SENSE Ver

8 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION 17.5V 17 5k V Received Signal Strength Indicator Output Pin 11 outputs DC level proportional to the log of input signal level to pin 2. V Sense Level Input External reference voltage of comparator 18 SENSE 18 LEVEL 19 GND V Ground Mixer Input The mixer is designed to work up to 47MHz with the typical input impedance of RinM = 5Ω and CinM = 2pF(at 43MHz). 2 MIX IN.27V 2 5 Note : 1. ESD protection diodes exist between each of the following pins and V. Pin 1,2,3,5,6,7,8,9,1,11,12,13,17,18,2 2. ESD protection diodes also exist between each of the following pins and ground. Pin 1,2,3,5,6,7,8,9,1,11,12,13,14,15,16,17,18 8 Ver.21839

9 APPLICATION CIRCUIT External Local Oscillator Signal Input CARRIER FSK SENSE V V SWITCH Hi Lo BPF LNA Input Imp.5ohm OSC MIXER BUFFER COMP V FSK COMP IF AMP C DEC C REF FILTER AMP External Oscillator IF FILTER DET TANK QUAD DET V Local Oscillator with External Crystal and LC Resonant Elements CARRIER FSK SENSE V V SWITCH Hi Lo V Input Imp.5ohm OSC MIXER BUFFER COMP V FSK COMP IF AMP C DEC C REF FILTER AMP QUAD DET Overtone Crystal Unit IF Filter DET Tank V Ver

10 EVALUATION PC BOARD The evaluation board is useful for your design and to have more understanding of the usage and performance of this device. This circuit is the same as TEST CIRCUIT. Note that this board is not prepared to show the recommendation of pattern and parts layout. Circuit Diagram SENSE LEVEL CARRIER FSK SENSE SW Hi Lo AF RF IN R6 1k V R5 1k C6.1 R4 68k R2 68k C1 C9 C7 1p 1 56p p R3 68k C8 33p LO IN R8 51 OSC MIXER BUFFER COMP FSK COMP FILTER AMP C p V C1 1p NC IF FILTER C13 1u C2.1u B A C2 Position IF AMP C4.1u R9 51 C12 1u IF IN NC C5 33p CD QUAD DET R1 3.3k V Note: 1. This board is designed for mixerinput type and C2 is factoryconfigured as follows: C2 : in the B position For the case of IFinput type, the position of C2 is necessary to change as follows: C2 : in the A position The actual position of C2 is shown in the next page. 2. External components CD : Ceramic Discriminator, 455kHz IF FILTER : Ceramic Filter, 455kHz 1 Ver.21839

11 Circuit Side View Position of C2 for the case of IFinput type Local IN RF IN R8 C1 C1 SENSE LEVEL R1 C2 CF IC1 NJM2592 C9 IF IN R9 C12 CF C4 C5 R7 R2 C6 C7 R4 C8 R3 R6 CD R1 SW R5 CARRIER SENSE C11 SW FSK V AF Vcc : Charge ON GND: Charge OFF Ground Side View Note: 1. External Components C1, C3, C9, C1=1pF C2, C4=.1uF C5=33pF C6=.1uF C7=56p C8=33pF C11=.47uF C12, C13=1uF R1=3.3kΩ R2, R3, R4=68kΩ R5, R6=1kΩ R7, R1=Ω R8, R9=51Ω CF : Ceramic Filter, 455kHz CD : Ceramic Discriminator, 455kHz Ver

12 TYPICAL CHARACTERISTICS ( Ta=25 C, V =2.V, unless otherwise noted ) 3. Current Consumption versus Supply Voltage No input signal 3 Mixer Conversion Gain versus Supply Voltage Measured at Pin3, terminated with 2kΩ Current Consumption Iccq(mA) Mixer Conversion Gain Gmix(dB) Fmix=4MHz Fmix=1MHz Supply Voltage V(V) Supply Voltage V(V) Demodulated Output versus Supply Voltage FSK Duty Ratio versus Supply Voltage 12 6 Demodulated Output Level Vod(mVrms) Duty Ratio of Wave Shaped Output (%) SW=OFF SW=ON Supply Voltage V(V) Supply Voltage V(V) S/N versus Supply VoltageMixer Input 3dB Limiting Sensitivity versus Supply Voltage 1 Condition 2(Mixer input) 3 Signal to Noise Ratio S/N1(dB) Limiting Sensitivity Vin(lim) (dbuvemf) Supply Voltage V(V) Supply Voltage V(V) 12 Ver.21839

13 Mixer Conversion Gain versus Frequency Mixer Input Level Characteristics 3 Measured at Pin3, terminated with 2kΩ 12 Mixer Output Level 6. Mixer Conversion Gain Gmix(dB) Mixer Output Level (dbuv) Current Consumption Current Consumption Iccq(mA) Mixer Input Frequncy fmix(mhz) Mixer Input Level VinMIX(dBm) Mixer Conversion Gain versus OSC Input AF Output versus Frequency:SCurve 3 Measured at Pin3, terminated with 2kΩ 8 Mixer Conversion Gain Gmix(dB) fmix=4mhz fmix=1mhz AF Output Voltage (mv) Local OSC Input Level (dbuvemf) IF Frequency fif(khz) IF Detuning (db) IF Detuning Characteristics Relative Frequency to fif (khz) Comparator Output Voltage (V) Carrier Sense Characteristics Conditon 1(IF input), SENSE LEVEL=.8V Output Voltage Vrssi(V) Ver

14 SN,N,AMR versus Mixer Input SN,N,AMR versus IF Input 1 Condition 2(Mixer input), AM=3% SN 1, AM=3% SN 1 1 SN,N,AMR(dB) AMR SN,N,AMR(dB) AMR 6 7 N 6 7 N Mixer Input Level VinMIX(dBuVEMF) IF Input Level VinIF(dBuVEMF) Output versus Mixer Input Output versus IF Input 2.4 Condition 2(Mixer input) 2.4 Output Voltage Vrssi(V) V=9.V V=4.V V=2.V Output Level Vrssi(V) V=9.V V=4.V V=2.V Mixer Input Level VinMIX(dBuVEMF) IF Input Level VinIF(dBuVEMF) Quick Charge/Discharge Current versus FSK Reference Input Voltage Quick Charge/Discharge Current Ich(uA) Condition1 (IF input),lpf =.45V FSK Reference Input Voltage(mV) 14 Ver.21839

15 Current Consumption Iccq(mA) Current Consumption versus Temperature No input signal Mixer Conversion Gain Gmix(dB) Mixer Conversion Gain versus Temperature Measured at Pin3, terminated with 2kΩ fmix=4mhz fmix=1mhz Demodulated Output versus Temperature FSK Duty Ratio versus Temperature 12 6 Demodulated Output Level Vod(mVrms) Duty Ratio DR(%) S/N versus Temperature 3dB Limiting Sensitivity versus Temperature 7 3 Signal to Noise Ratio S/N1,S/N2(dB) Condition 2(MIX input) Limiting Sensitivity Vin(lim) (dbuvemf) Condition 2(MIX input) Ver

16 Output versus TemperatureMixer Output versus TemperatureIF 2.4 Condition 2(Mixer input) 2.4 Output Voltage Vrssi(V) dBuVEMF 6dBuVEMF 5dBuVEMF 4dBuVEMF 3dBuVEMF 2dBuVEMF Output Voltage Vrssi(V) dBuVEMF 6dBuVEMF 5dBuVEMF 4dBuVEMF 3dBuVEMF 2dBuVEMF Quick Charge/Discharge Current versus Temperature 2,LPF =.45V Quick Charge/Discharge Current Ich(uA) [CAUTION] The specifications on this databook are only given for information, without any guarantee as regards either mistakes or omissions. The application circuits in this databook are described only to show representative usages of the product and not intended for the guarantee or permission of any right including the industrial rights. 16 Ver.21839