NJM2550 10.7MHz INPUT FM IF DEMODULATOR GENERAL DESCRIPTION PACKAGE OUTLINE The NJM2550 is a wide-operating voltage, low-current FM IF demodulator IC with 10.7MHz(standard) IF frequency. It includes a limiting amplifier, quadrature detector, filter amplifier, FSK/ASK(OOK) comparator, RSSI thermal characteristics correction, and quick charge circuit The NJM2550 is suitable for low power, narrow band receiver for short range data/voice transmission by using IF=10.7MHz or IF/carrier frequency of up to 50MHz. NJM2550V FEATURES Wide Range Operating Voltage Low Operating Current Wide Range IF Input Frequency 2V to 9V 4.4mA at V+ =3V 10.7MHz (standard) 5MHz to 50MHz (reference value) 1MHz (reference value) 2Mbps (reference value) Wide Band FM Detector Circuit High-speed Transmission Rate FSK/ASK (OOS) Comparator Two External Resistors to Adjust RSSI ‘s Thermal Characteristics Bipolar Technology Package Outline SSOP16 BLOCK DIAGRAM RSSI OUT 16 CHARGE COMP SWITCH OUT 15 14 COMP REF 13 COMP IN 12 FSK VREF 11 AMP OUT 10 AMP IN 9 BUFF AMP + -- COMP + - CHARGE RSSI QUAD DET IF AMP Ver.2006-02-24 1 2 3 4 5 6 7 8 RSSI REF GND IF IN DEC V+ IF OUT QUAD IN AF OUT -1- NJM2550 ABSOLUTE MAXIMUM RATINGS PARAMETER (Ta=25°C) SYMBOL RATINGS UNIT Supply Voltage V+ 10.0 V Power Dissipation PD 300 mW Operating Temperature Topr - 40 to +85 °C Storage Temperature Tstg - 40 to +125 °C RECOMMENDED OPERATIONAL CONDITION PARAMETER Supply Voltage SYMBOL TEST CONDITIONS (Ta=25°C) MIN. TYP. MAX. UNIT 2.0 3.0 9.0 V MIN. TYP. MAX. UNIT - 4.4 5.8 mA - 330 - Ω VinIF=80dBuV - 60 - dB f i f = 10.7MHz - 30 - f i f = 50MHz - (40) - 80 120 180 mVrms V+ ELECTRICAL CHARACTERISTICS (Ta=25°C, V+=3 V, f i f=10.7MHz, fmod=1kHz, fdev=±100kHz, unless otherwise noted) PARAMETER SYMBOL Current Consumption Iccq IF Amplifier Input Resistance Rin Signal to Noise Ratio 1 S/N1 - 3dB Limiting Sensitivity TEST CONDITIONS No Signal V COMP REF=0.6V V COMP IN = 0.65V Vin(lim) dBuV Demodulated Signal Level V od VinIF=80dBuV Demodulated Signal Frequency Characteristics fDET Based on fmod=1kHz Measured at –3dB - 1 - MHz Buffer Amplifier Gain Gamp 1MHz -1 0 1 dB AM Rejection Ratio AMR VinIF=80dBuV AM=30% - 50 - dB Duty Ratio of Wave Shaped Output DR VinIF=80dBuV 40 50 60 % Quick Charge / Discharge Current I ch V COMP REF=GND V COMP IN = 0.3V 120 210 300 uA - 3 - V - 0.1 - V High Level Voltage of VfskH 1kΩ load COMP OUT Terminal Low Level Voltage of VfskL 1kΩ load COMP OUT Terminal The values shown in parenthesis are reference values. Ver.2006-02-24 -2- NJM2550 PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT - 65 - dB RSSI Dynamic Range ∆ RSSI Low Level Voltage of RSSI VrssiL No signal - 100 - mV High Level Voltage of RSSI VrssiH VinIF=110dBuV - 1.55 - V RSSI Output Voltage 1 Vrssi1 VinIF=80dBuV - 1.2 - V RSSI Output Voltage 2 Vrssi2 f i f =50MHz, VinIF=80dBuV - 1.15 - V 1pin Terminal Voltage V 1p 33kΩ load - 1.1 - V MIN. TYP. MAX. UNIT - 50 - usec - 600 - usec - 20 - usec - 600 - usec REFERENCE (Ta=25°C, V+=3 V, f i f=10.7MHz, fmod=1kHz, fdev=±100kHz, unless otherwise noted) PARAMETER SYMBOL - RSSI Output Signal Rise-up Time FM Demodulated Signal Rise-up Time - Ver.2006-02-24 TEST CONDITIONS V+ =on IF Signal = off on IF Signal=on V+ = off on V+ =on IF Signal = off on IF Signal=on V+ = off on -3- NJM2550 TEST CIRCUIT This test circuit allows the measurement of all parameters described in “ELECTRICAL CHARACTERISTICS”. This test circuit includes an electrical switch that should be in the suitable position for the measurement of each parameter. Circuit Diagram CHARGE SWITCH RSSI OUT V+ 100k 100k 100k 1000p 7.5k AMP OUT 3300p COMP OUT 68k 10u 330p + 16 15 14 13 12 11 10 68k 68k 1000p 9 BUFF AMP ++ -- COMP + - CHARGE RSSI QUAD DET IF AMP 1 2 3 4 0.01u 33k 30p 51 RSSI REF 5 6 7 0.01u V+ R50 + IF IN 8 2p R10 1k V+ 10u 0.1u Tquad AF OUT External Components • f i f =10.7 MHz Tquad : IF transformer for detection, 4165-T070 (Sumida corporation) R10 : 1kΩ R50 : open • f i f =50MHz Tquad : IF transformer for detection, 2261-T080 (Sumida corporation) R10 : 1kΩ R50 : 7.5 kΩ • The external resistors connected to1pin and 16pin should have the same thermal coefficient. Ver.2006-02-24 -4- NJM2550 TERMINAL FUNCTION (Ta=25°C, V+=3 V) Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE V+ 1 RSSI REF 1 1.12V 50k FUNCTION RSSI Reference Current Control To control RSSI reference current, a resistor is connected to pin1 and pin6, respectively. The recommended value is 33kΩ. By choosing the different thermal coefficient of these two resisters, RSSI thermal characteristics can be changed. GND 2 GND -- -V+ 3 64k IF IN 165 2.46 DEC IF Limiter Amplifier Input The typical input impedance is 330Ω. 165 IF Decoupling An external decoupling capacitor is connected to enhance stability. 3 4 Ground 4 2.46V GND Supply Voltage 5 5 V+ V+ -GND IF Limiter Amplifier Output An external phase-shifting coil or discriminator is connected between pin6 and pin7. V+ 6 IF OUT 2.06V 6 140uA GND Ver.2006-02-24 -5- NJM2550 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE Quadrature Detector Input An external phase-shifting coil or discriminator is connected between pin6 and pin7. V+ 400 7 QUAD IN 7 FUNCTION 400 -- Note that supply voltage should be the same as the voltage supplied to pin5. 95uA GND Demodulated Signal Output An external 3rd order multiple feedback filter(RC filter) is connected between pin8 and pin9. V+ 8 AF OUT 0.61V 8 44uA GND -- Buffer Amplifier Input A set of external RC component forms a low pass filter between pin9 and pin10. -- Buffer Amplifier Output A set of external RC component forms a low pass filter between pin9 and pin10. V+ 9 20uA AMP IN 10 9 10 210uA AMP OUT GND V+ 11 FSK VREF 0.61V 11 35k FSK Reference Voltage Output This pin usually keeps open. This fixed output voltage may be available for the FSK reference voltage by connecting to pin13. This usage is effective in shaping the data signal with continuous bits of the same polarity. Note that this usage is under consideration GND Ver.2006-02-24 -6- NJM2550 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION Comparator Input This pin is an input of the wave shaping comparator. 20uA 12 COMP IN 12 -- 20uA 20uA GND V+ 13 COMP REF 13 -- GND 14 14 COMP OUT -GND V+ 10uA 15 CHARGE SWITCH 15 -- 300k Comparator Reference Input This pin is an input of reference voltage for the wave shaping comparator. A capacitor is connected to create an average DC Level of FM demodulated signal. The value of this capacitor is dependant on the speed of data signal. A quick charge /discharge circuit offers the voltage of pin13 comes the average DC Level of FM demodulated signal very quickly. Comparator Output An open-collector output. The comparator is non-reverse type. When the frequency of IF input signal is fif +∆, the output is “Low”. When the frequency of IF input signal is fif -∆, the output is “High”. Instead of V+, another power source can be used within the limit of the rated supply voltage. Quick Charge / Discharge Circuit ON / OFF Control The quick charge/discharge circuit is in the active stage when pin15 is pulled up to V+. This circuit is in the stand-by stage when pin15 is pulled down to GND. Instead of V+, another power source can be used within the limit of the rated power supply voltage. GND Ver.2006-02-24 -7- NJM2550 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE V+ 16 RSSI OUT FUNCTION RSSI Output Pin16 outputs DC level proportional to the log of IF input signal level to pin3. -- 16 GND • Ver.2006-02-24 Note : 1. ESD protection diodes exist between each of the following pins and V+ Pin 1,3,4,6,8,9,10,11,16 2. ESD protection diodes also exist between each of the following pins and ground. Pin 1,3,4,6,7,8,9,10,11,12,13,14,15,16 -8- NJM2550 EVALUATION BOARD This evaluation board may be useful for your design and to have more understanding of the usage and performance of this device. The circuit diagram and test condition of this board is the same as TEST CIRCUIT. Note that this board is not prepared to show you the recommendation of pattern and parts layout. Circuit Diagram SW1 CHARGE to V+ SWITCH RSSI OUT R20 100k R21 C22 7.5k 1000p 16 AMP OUT COMP OUT R18 100k C19 10u R17 100k 3300p C16 R14 330p 68k + 15 14 13 ++ -- C15 12 11 10 9 68k R11 68k C12 1000p BUFF AMP COMP + - R13 IC1 NJM2550 CHARGE RSSI QUAD DET IF AMP 1 R2 33k 2 4 C3 0.01u C1 30p RSSI REF V+ 3 R4 51 5 6 C5 0.01u to V 7 + R50 C8 2p R10 to V+ 1k +C6 C7 10u 0.1u IF IN 8 T9 : 4165-T070 AF OUT Note: 1. This board is designed for f i f =10.7MHz. For f i f =50MHz, please change T9 ,R10, and R50 as follows. • f i f =10.7 MHz (factory-configured) T9 : IF transformer for detection, 4165-T070 (Sumida corporation) R10 : 1kΩ R50 : open • f i f =50MHz T9 : IF transformer for detection, 2261-T080 (Sumida corporation) R10 : 1kΩ R50 : 7.5 kΩ 2. This board is designed for fdev=±100kHz. For fdev=±10kHz, please refer to the values shown below. • Ver.2006-02-24 fdev=±100kHz (factory-configured) Tquard related values : L=4400nH, Q=80 Rquad=1kΩ -9- NJM2550 • fdev=±10kHz Tquard related values :L=4400nH, Q=110 Rquad=30kΩ 3. The external resistors connected to1pin and 16pin have the same thermal coefficient. By changing these thermal coefficients, RSSI thermal characteristics can be changed. 4. This board is designed to supply voltage to CHARGE SWITCH, the pull-up of COMP OUT, and the quadrature circuit from the common power source. NJM2550 permits each of CHARGE SWITCH and pull-up of COMP OUT to have another power source within the limit of the rated power supply voltage. Note that the voltage supplied to the quadrature circuit should be the same as the voltage supplied to pin5. 5. List of Components Ver.2006-02-24 Item Resistor Number R2 R4 R10 R11 R13 R14 R17 R18 R20 R21 R50 value 33k 51 1k 68k 68k 68k 100k 100k 100k 7.5k open IC Switch Transformer IC1 SW1 T9 NJM2550 --------4165-T070 Item Capacitor Number C1 C3 C5 C6 C7 C8 C12 C15 C16 C19 C11 value 30p 0.01u 0.01u 10u 0.1u 2p 1000p 3300p 330p 10u 1000p - 10 - NJM2550 Pattern Layout 10uF COMP OUT OFF 20 19 100kΩ 100kΩ 18 CHARGE SW ON RSSI OUT 21 AMP OUT 100kΩ 17 330pF 68kΩ 22 14 15 7.5kΩ1000pF NJM2550 16 3300pF 12 13 68kΩ RSSI REF 1000pF 11 68kΩ 1 2 30pF 33kΩ 5 8 0.01uF AF OUT 2pF 9 4165-T070 (Sumida Corportion) 10 1kΩ 3 V+ 0.01uF 7 0.1uF 51Ω GND 4 IF IN 6 10uF Ver.2006-02-24 - 11 - NJM2550 TYPICAL CHARACTERISTICS Demodulated Signal Level versus Supply Voltage Current Consumption versus Supply Voltage fdev=±100kHz, fmod=1kHz, VinIF=80dBuV 180 CHARGE SWITCH=ON FM Demodulated Signal Level Vod(mVrms) Current Consumption Iccq(mA) 6 5 CHARGE SWITCH=OFF 4 3 2 1 160 140 fif=10.7MHz 120 100 fif=50MHz 80 0 60 0 2 4 6 8 10 0 2 Supply Voltage V+(V) 8 fdev=±100kHz, fmod=1kHz, AM=30% fdev=±100kHz, fmod=1kHz, AM=30% 70 fif=10.7MHz 60 fif=50MHz 50 40 50 40 fif=10.7MHz 30 fif=50MHz 20 10 0 2 4 6 8 10 0 2 Supply Voltage V+(V) 4 6 8 10 Supply Voltage V+(V) S+N,N,AMR versus IF Input Level-50MHz- S+N,N,AMR versus IF Input Level-10.7MHzfif=10.7MHz, fdev=±100kHz, fmod=1kHz, AM=30% 0 0 fif=50MHz, fdev=±100kHz, fmod=1kHz, AM=30% S+N S+N -10 -10 S+N, N, AMR (dB) S+N, N, AMR (dB) 10 -3dB Limiting Sensitivisy versus Supply Voltage -3dB Limiting Sensitivity Vin(lim) (dBuV) Signal to Noise Ratio S/N(dB) 6 Supply Voltage V+(V) S/N versus Supply Voltage 80 4 -20 -30 -40 AMR -50 -20 -30 AMR -40 -50 -60 -60 N N -70 -70 0 20 40 60 80 100 IF Input Level VinIF(dBuV) Ver.2006-02-24 120 0 20 40 60 80 100 120 IF Input Level VinIF(dBuV) - 12 - NJM2550 RSSI Output versus IF Frequency RSSI Output versus IF Input 1.6 fif=10.7MHz 1.6 RSSI Output Voltage Vrssi(V) RSSI Output Voltage Vrssi(V) 1.8 1.4 1.2 1 fif=50MHz 0.8 0.6 0.4 0.2 0 1.4 VinIF=80dBuV 1.2 1 0.8 0.6 VinIF=40dBuV 0.4 0.2 0 0 20 40 60 80 100 120 1 10 IF Input Level VinIF(dBuV) AF OUT versus IF Frequency(S Curve)-10.7MHz- 2.5 100 IF Frequency fif (MHz) AF OUT versus IF Frequency(S Curve)-50MHzVinIF=80dBuV VinIF=80dBuV 2.5 AF OUT Voltage (V) AF OUT Voltage (V) V+=9V 2 V+=3V 1.5 V+=2V 1 0.5 0 2 V+=9V V+=3V 1.5 V+=2V 1 0.5 0 9.5 10 10.5 11 11.5 49 IF Frequency fif (MHz) 51 90 Simulation 85 fif=10.7MHz 80 IF AMP Gain (dB) Demodulated Signal Level Vod(mVrms) 50.5 IF AMP Gain versus IF Frequency fdev=±100kHz, VinIF=80dBuV 120 50 IF Frequency fif (MHz) Demodulated Signal Frequency Characteristics 140 49.5 100 fif=50MHz 80 60 40 75 70 65 60 55 50 20 45 0 40 10 100 1000 FM Modulation Frequency(kHz) Ver.2006-02-24 10000 1 10 100 IF Frequency fif (MHz) - 13 - NJM2550 Demodulated Signal Level versus Temperature Current Consumption versus Temperature CHARGE SWITCH=ON 5 4 CHARGE SWITCH=OFF 3 2 1 180 FM Demodulated Signal Level Vod(mVrms) Current Consumption Iccq(mA) fdev=±100kHz, fmod=1kHz, VinIF=80dBuV No input singal, COMP REF=0.6V, COMP IN=0.65V 6 160 140 fif=10.7MHz 120 100 fif=50MHz 80 0 60 -40 -20 0 20 40 60 80 100 120 -40 -20 Ambient Temperature Ta(°C) 70 fif=10.7MHz 60 fif=50MHz 50 -3dB Limiting Sensitivity Vin(lim) (dBuV) Signal to Noise Ratio S/N(dB) 40 60 80 100 120 fdev=±100kHz, fmod=1kHz, AM=30% fdev=±100kHz, fmod=1kHz, AM=30% 50 40 fif=50MHz 30 fif=10.7MHz 20 10 40 -40 -20 0 20 40 60 80 -40 -20 100 120 RSSI Output versus Temperature-10.7MHzfif=10.7MHz 1.8 VinIF=100dBuV 1.6 1.4 VinIF=80dBuV 1.2 1 VinIF=60dBuV 0.8 0.6 20 40 60 80 100 120 RSSI Output versus Temperature-50MHz- VinIF=40dBuV 0.4 0.2 0 RSSI Output Voltage Vrssi(V) 1.8 0 Ambient Temperature Ta(°C) Ambiet Temperature Ta(°C) RSSI Output Voltage Vrssi(V) 20 - 3dB Limiting Sensitivity versus Temperature S/N versus Temperature 80 0 Ambient Temperature Ta(°C) fif=50MHz VinIF=100dBuV 1.6 1.4 VinIF=80dBuV 1.2 1 VinIF=60dBuV 0.8 0.6 VinIF=40dBuV 0.4 0.2 0 -40 -20 0 20 40 60 80 100 120 Ambient Temperature Ta(°C) Ver.2006-02-24 -40 -20 0 20 40 60 80 100 120 Ambient Temperature Ta(°C) - 14 - NJM2550 Duty Ratio of Wave Shaped Output DR(%) Duty Ratio versus Temperature VinIF=80dBuV 60 50 40 -40 -20 0 20 40 60 80 100 120 Ambient Temperature Ta(°C) [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. Ver.2006-02-24 - 15 -