NJM2549 WIDE BAND FM IF DEMODULATOR ! GENERAL DESCRIPTION ! PACKAGE OUTLINE The NJM2549 is a wide band IF IC with a maximum IF input frequency of 15 MHz. It includes an IF Amplifier, Quadrature Detector, RSSI and IF Balanced Output. ! # # # # # ! ! NJM2549RB2 MAIN APPLICATIONS RF ID Radar detector Wireless Infrared Communication System Voice Transmission System A few MHz band Signal Detector FEATURES # # # Wide Range Operating Voltage Low Operating Current Wide Range IF Input Frequency # # # # # # Wide Band FM Detector Range RSSI Quick Response High FM Detection Sensitivity IF Amplifier with Balanced Output Bipolar Technology Package Outline 2.7V to 9V (recommended supply voltage) 3mA (standard) 10.7MHz (standard) 100kHz to 15MHz (reference value) DC to 1MHz (reference value) 22dBuV (- 3dB Limiting Sensitivity) TVSP10 BLOCK DIAGRAM AF OUT QUAD IN IF OUT1 IF OUT2 RSSI OUT 10 9 8 7 6 QUAD DET IF AMP 1 2 3 4 5 + IF IN IF DEC1 IF DEC2 GND V Ver.2011-09-26 RSSI -1- NJM2549 ! EXPLANATION Functional Block Diagram V AF OUT + RSSI OUT FM Demodulator T1 10.7MHz C7 0.01u C6 82p R2 2.4k C4 100p PHASE SHIFTER C5 3p 10 9 8 7 6 QUAD DET RSSI IF AMP RSSI 1 2 3 C1 0.01u C9 10u C8 0.01u 4 C2 0.01u 5 C3 0.01u R1 51 IF Amplifier IF IN General The frequency- converted RF signal goes through an external narrow or wide bandwidth BPF and is inputted to Pin 2 as unbalanced input, otherwise inputted to Pin2 and Pin3 as balanced input. The available frequency range of IF signals are from 100kHz to 15MHz. The IF amplifier is a limiting amplifier with 75dB gain and converts IF input signal to an amplitude - limiting IF signal. The FM demodulator consists of an external phase shifter circuit and an internal quadrature detector. It demodulates the amplitude - limiting IF signal and outputs to Pin10 as AF output signal. The demodulated AF output signal is the rail-to-rail output of 2.7Vpp with the maximum bandwidth of up to 1MHz. Pin6 is the output of RSSI circuit, which outputs DC level proportional to the log of input signal level to Pin 2. NJM2549 has other remarkable functions: balanced input/ output (Pins 2, 3, 7and 8), and pin-selectable for either of two demodulation characteristics (Pin7and 8). IF Amplifier (Pins 2, 3, 4, 7, and 8) Input impedance Pin2 and Pin 3 are the input terminal for IF input signal. Pin2 is used for unbalanced input, and a pair of Pin 2 and Pin3 is used for balanced input. As one general example of unbalanced input, IF signal is supplied to Pin 2 through an external band-pass filter and a matching resistor R1 in parallel. In general, the matching impedance of the filter is 330ohm. Pin 2 is designed to have input impedance of 10kohm much higher than 330ohm, and R1 should be 330ohm Ver.2011-09-26 -2- NJM2549 RSSI OUT V+ 6 RSSI NJM2549 1 FM Demodulator 15k C2 BPF 50k S-curve Unbalanced Output Balanced IF Output 7 8 2 Zbpf 90 Phase Shifter N- C1 R1 9 IF Limitter Amplifier IF AMP 3 AF Output o RSSI 10k 10 10k 50k 5 4 GND C3 as the same value of the matching impedance. When you connect measurement equipment to Pin2, recommended value of R1 is 50ohm that is the same value of output impedance of the equipment. For the case of unbalanced input, a decoupling capacitor C2 is necessary to locate between Pin 3 and GND line. The impedance of this decoupling capacitor should be adequately low at IF frequency to keep Pin3 close to the GND line level of NJM2549. Note that for larger value of decoupling capacitance, startup-waiting time of operating voltage is longer because of larger time constant formed by the capacitance and the input impedance of Pin3. For your reference, our evaluation board uses 0.01uF for 10.7MHz IF frequency. IF AMP Gain versus IF Frequency and Terminal Capacitance 100 C1=C2=C3 =1uF 80 GIF ( dB ) Gain IF limiter amplifier is a six-stage differential amplifier with balanced inputs of Pin2 and Pin3. The IF input signal is amplified and then supplied to both of the internal quadrature detector and the external phase shifter of FM demodulation circuit. Total gain of the IF limiter amplifier is so high value, approximately 75dB at 10.7Hz that the output signal is an amplitude- limiting signal. This output signal is like a square wave that is required for the normal operation of FM demodulation. The gain is changed by the IF input frequency and the value of the external capacitors of C1, C2 and C3, as shown in the figure. It is recommended that these three capacitors have the same values in capacitance to harmonize each startup-waiting time of operating voltage. C1 is a DC cut capacitor. C2 is a decoupling capacitor when pin2 is unbalanced input. C3 is a noise removal capacitor to remove noise on the resistor feedback path. 60 10nF 3.3nF 1nF 40 20 0 0.1 1 10 100 IF Input Frequency ( MHz ) Balanced input / output NJM2549 features balanced input. It is available to connect directly to the balanced output circuit that precedes NJM2549. When input signal is small so that output signal of IF amplifier is not limited amplitude, balanced input is effective to remove common noise from input signal. When FM demodulator circuit is not required and NJM2549 uses just for a high gain limiter amplifier, the balanced output can be available. This is effective to reduce the susceptibility of external noise while allowing the usage of longer line between the output terminals and the next stage. Ver.2011-09-26 -3- NJM2549 RSSI OUT V+ 6 RSSI 1 NJM2549 FM Demodulator 15k RSSI 50k 10k C1 AF Output 9 90 deg. Shifter N- IF Limitter Amplifier IF AMP 3 10 S-curve Unbalanced Output Balanced Output 7 8 2 10k C2 Balanced Input 50k 1 Balanced Output 5 4 C3 Easy to reject comon mode noise on long line 1 GND 2 70 7 3 70 10k 8 10k 4 50k 400uA 50k 300uA 5 300uA 5 Output level at pin7and pin8 The output level at each of Pin7and Pin8 is Typ.425mVpp with the external load resistor RL of 15kohm connected from output to ground under the standard measurement condition. In order to avoid over current and obtain desired output level, the external load resistor of over 15kohm is recommended for each pin. The output current is Typ.290mA under the same condition. 7 RL1 VOIF=425mVpp Typ. @RL1=15kohm RL2 VOIF=425mVpp Typ. @RL2=15kohm 8 FM Demodulator (Pins 7 to 10) The signal from IF amplifier is put into the FM demodulator. The FM demodulator is composed of an internal quadrature detector and an external phase shifter. The quadrature detector is a multiplier and needs two kinds of input signal. One is the original IF signal including a carrier signal and a FM modulated signal. The other is 90-degree shifted IF signal, which is the output of the phase shifter. The demodulated signal from the quadrature detector is brought out at Pin 10. Note that the supply voltage to phase-shifter should be the same as the supply voltage to Pin 1. AF OUT V Lq Cq Demodulated Signal + Rd 90 Phase Shifter Cp 10 Quadrature Detector 9 8 90phase shifted IF signal 7 IF Signal IF Signal Phase shifter The phase shifter is an external circuit that is composed of a capacitor and RLC resonant circuit. The capacitor is placed between Pin9 and Pin8 (or between Pin9 and Pin7) to increase the IF signal to the external parallel RLC resonant circuit that provides the 90-degree phase shift and drives the quadrature detector. Pin 9 provides for the external RLC parallel resonant circuit and the internal connection to the quadrature detector. Instead of LC resonant circuit, a ceramic discriminator can be also used and it is very useful to delete a frequency adjustment and obtain higher Q. The resonant frequency of the ceramic discriminator or the LC resonant circuit is the same as IF frequency of IF input signal. In general, Ver.2011-09-26 -4- NJM2549 most of ceramic discriminators are designed for the specific ICs to optimize some important performance of the FM demodulator. The ceramic discriminator CD: CDSCB10MGA144-R0 (Murata Manufacturing Co., Ltd., Japan) is especially designed for NJM2549, when using IF frequency of 10.7MHz. Pin9 needs bias through a resistor. The bias voltage should be the same as the supply voltage V+. When the detector is not used, Pin9 should be connected to V+. The resistor Rd is not only used for bias but also for the adjustment of the important characteristics of the detector circuit. V AF OUT 90 Phase Shifter Rd CD Demodulated Signal + Cp 10 9 Quadrature Detector 8 7 90phase shifted IF signal IF Signal IF Signal VO DC ( V ) S-curve The S-curve is the characteristics of "detector output level versus IF frequency deviation". This characteristic is determined by the performance of the phase shifter. Demodulated DC Level versus Frequency The following mentions how to determine the value of the phase ( S-curve, BW:200kHz, Supply Voltage ) shifter. The quadrature detector is coupled to the IF with and a 5 capacitor Cp between Pin9 and Pin8 (or between Pin9 and Pin7). For wideband applications, the drive to the detector can be 4 increased with this additional external capacitor and the V+ =9.0V demodulated signal level output is increased for a given bandwidth. 3 3.0V The wideband performance of the detector is controlled by the 2.7V loaded Q of the LC tank circuit. The following equation defines the fif=10.7MHz 2 components which set the detector circuit's bandwidth: Q=Rd / X 1.1V Typ. 1 where Rd is the equivalent shunt resistance across the LC tank. X is the reactance of the quadratue inductor at the IF frequency (X=2 0 fif L). The inductor and capacitor are chosen to form a resonant LC 10.6 10.65 10.7 10.75 10.8 tank at the desired IF center frequency as predicated by; fif= 1 2 LqCq IF Input Frequency ( MHz ) where Ld is the parallel tank inductor, C9 is the equivalent parallel capacitance of the parallel resonant tank circuit. The following is one of the examples of actual step to obtain the suitable values of Cp, Cq, Lq and R. 1. Determine the value of Cq and Lq from the relative expression as shown above.It is very convenient to use an IF transformer with built-in Cq, which has high Q and the resonance frequency of fif. 2. Add a capacitor of a few pF as Cp and measure S-curve. Change Cp until the center frequency of S-curve comes to the resonance frequency of fif a. Considering the following items, choose Rd. b. The position of fif is at the center of S-curve c. The position of fif-f and fif+f is on the linear area of S-curve. d. The frequency stability and accuracy of received RF signal and local signal are influenced to the stability of IF signal. e. If the stability is not so good, the position of fif-f should be located far from the bottom of S-curve. The position of fif+f should be also located far from the top of S-curve. In next page, there is a drawing that shows how to adjust S-curve to obtain the suitable demodulated signal. Ver.2011-09-26 -5- NJM2549 What determines its position and tilt angle of S-curve Demodulated Output Level versus IF Frequency Q or R2 become larger,tilt angle larger Output Level of S curve-2 X Output Level of S curve-1 X AF Out Level (Vdc) Q and Rd As the loaded Q of the LC tank circuit and Rd of shunt resistance across the LC tank become large, the tilt angle of S-curve increases. 1.5 1 0.5 S curve-1 S curve-2 10.68 11.69 10.7 10.71 10.72 fif (kHz) Cp becomes smaller, waveform shift to right Output Level of S curve-2 X Output Level of S curve-1 X AF Out Level (Vdc) Cp As the capacitor Cp between Pin9 and Pin8 (or between Pin9 and Pin7) becomes small, the S-curve shifts to the right side. 1.5 1 0.5 S curve-2 S curve-1 a. Small output level The carrier of FM modulation signal moves 10.68 11.69 10.7 10.71 10.72 b.Compressed waveform fif (kHz) from fif-fdev to fif+fdev. Total width of FM Deviation of IF signal fif fdev deviation is the double of fdev. When the width of FM deviation is within the linear area of S-curve, FM demodulation is done well. If the H width of FM deviation is too large and the X HL frequency of fif-fdev and fif+fdev is out of the L L linear area, FM demodulation is not done well. H L Or you have to change Rd or Q of tank circuit to fif-f fif fif+f make the linear area wider. For example, if the center frequency of IF input signal is 10.7MHz and maximum FM deviation is +- 5kHz, FM demodulated signal has the frequency range of 10.695MHz to 10.705MHz. This frequency range is within the linear area of S-curve-0. If the maximum FM deviation is +-10kHz, this signal will move from10.69MHz to 10.71MHz. This signal is demodulated on the non-linear area and may have big distortion. Changing the value of the external resistor Rd and Q of the tank circuit, the width of linear area on the S-curve can be adjusted, as shown as S curve-1. When the linear area becomes wider, the demodulated output level becomes smaller because tilt angle of S-curve smaller. In the case of +-50kHz of FM deviation, it is difficult to have such a wide linear area from 10.65MHz to 10.75MHz by reducing the value of the external resistor. How to measure S-curve characteristics Signal Generator 1 100,00 60 dBuV FM Multimeter Connection AM Signal Generator : R&S SMY02 A COM RF Multi-meter : Digital volt meter with high input impedance Power supply How to measure Power Supply IF in AFout 1. Set supply voltage of Power supply Evaluation NJM2597 2. Set RF output level and IF frequency (fif) of Signal generator V+ GND 3. Set DCV mode of Mutimeter 4. Supply DC voltage to evaluation board 5. Change IF frequency from fif - 15kHz (or 20kHz) to fif + 15kHz (or 20kHz) by 1kHz step 6. Read output DC voltage of mulitmeter by each IF frequency Ver.2011-09-26 -6- NJM2549 Selectable two modes of S-Curve or N-curve The characteristics of "detector output level versus IF frequency deviation " is available in two modes selectable via Pin7 and Pin8. One is, as explained, S-curve and the other is N-curve. The S-curve characteristic features S-like shape of the curve. So we call "S-curve". According to the S-curve characteristic, as the frequency of IF carrier signal goes up, the AF output level increase. On the other hand, the N-curve characteristic features N-like shape of the curve, and the AF output level increase as the IF carrier frequency goes down. Demodulated Output Level versus IF Frequency S curve N curve AF Output Signal AF Out Level (Vdc) X AF Out Level (Vdc) AF Output Signal Demodulated Output Level versus IF Frequency 1.5 1 X 0.5 10.68 11.69 10.7 10.71 1.5 1 0.5 10.72 10.68 11.69 10.7 fif (kHz) 10.71 Deviation of IF signal fif fdev Deviation of IF signal fif fdev X fif-f fif 10.72 fif (kHz) X fif+f fif-f fif AF OUT Pin 7 is a select pin for N curve, and pin8 is for S curve. It is recommended that you leave unused pin (Pin7 or Pin8) unconnected on the board, otherwise, terminated with resistor which value is the same as the load impedance of the used pin. V + Lq Cq Demodulated Signal fif+f Rd S- Cp 10 Quadrature Detector 9 N-curve 7 8 90phase shifted IF signal IF Signal IF Signal Demodulated DC Level versus Frequency and R2 3 R2= 4.7k 2.4k 1.2k 2 V O DC ( V ) AF output level The FM demodulated signal from the quadrature detector is brought out at Pin 10. AF output level at Pin10 is determined by deviation of IF signal, tilt angle of S-curve, external load resistance connected to Pin10 and supply voltage. The figure is the S-curve of NJM2549 measured under our standard test condition. The resulting curve shows how external resistor of R2 effects the tilt angle of S-curve and the expected maximum output level at Pin10, where R2 is an external resistor of FM demodulator used as the same meaning of Rd. 680 360 180 1 0 10.6 10.65 10.7 10.75 10.8 IF Input Frequency ( MHz ) Ver.2011-09-26 -7- NJM2549 The maximum output level is approximately 90% of supply voltage under the following condition: RL> V+ / 205uA where RL is the value of external load resistance connected to pin10. It is important to set DC level of detector output at Pin10 to center the peak-to-peak swing of the demodulated signal. In addition, tilt angle of S-curve should be high enough to obtain large output level. V+ 1 AFOUT 205uA 70 0.9 x V+ 10 RL 5 GND LPF for removing noise from AF output signal The frequency bandwidth of demodulated signal is up to 1000kHz under the standard measurement condition of NJM2549. This performance is much enough to use for low bit-rate data demodulation. On the other hand, AF output signal contains the factor of IF carrier signal and many harmonics and these noise factors exacerbate S/N (signal to noise ratio). A by-pass capacitor is useful to remove these noise factors. The 3rd-multiple feedback filter is a low pass active filter and more effective to remove the factor of high frequency signal from the demodulated output signal. It is composed of three resistors, three capacitors and an amplifier. The cut-off frequency fc of the filter is obtained by fc= 2 3 1 Hz RaRbRcCaCbCc where Ra=Rb=Rc or Ca=Cb=Cc In the case of digital data demodulation, fc is determined by the following formula. fc= 1 Baud x (1.5 to 2) 2 Examples of actual circuit are shown below. Cc Cc fc=1.9kHz INPUT Ra 68k Ca 1000p fc=27kHz 1.5n 3300p Rb 68k INPUT Rc + - 68k Cb 330p OUTPUT Ra 12k Ca 620p NJM2741 Rb 12k Rc OUTPUT + - 12k Cb 91p NJM2741 The following list shows an example of the external value. bps Ra Rb Rc Ca Cb Cc fc 512 68k 68k 68k 8200pF 1200pF 0.022uF 390Hz 1200 68k 68k 68k 3300pF 560pF 0.01uF 885Hz 2400 68k 68k 68k 1500pF 330pF 3300pF 1.99kHz 3200 30k 30k 30k 1500pF 680pF 4800pF 3.15kHz 6400 30k 30k 30k 820pF 330pF 2200pF 6.31kHz Simplified FM demodulator circuit Limited to specific applications, simplified phase shifter circuit of FM demodulator may be available. You may reduce external components. For more information, please contact us. Ver.2011-09-26 -8- NJM2549 RSSI (Pin6) RSSI Output versus IF Input Level and Supply Voltage 2.5 V+= 9.0V 2.0 3.0V, 2.7V 1.5 V RSSI ( V ) RSSI is a received signal strength indicator and outputs DC voltage, which voltage is proportional to the log of the IF signal amplitude. The internal resistance at pin 6 is around 15k ohm and RSSI output is voltage mode. The RSSI circuit provides dynamic range of typically 60dB. The change of RSSI output voltage has a transient response against the change of IF input signal level. The curve of RSSI response is determined by the two factors: 1.0 0.5 1. Time constant: T=CEXT x R0 RSSI 2. The difference of voltage: Vrssi(T1) - Vrssi(T2) where CEXT: external capacitance connected at pin6 R0 RSSI : RSSI Output Resistance (internal resistor) 0.0 0 20 40 60 80 100 IF Input Level ( dBuV ) NJM2549 has an internal resistance of 15kohm at Pin6. When CEXT=1nF, the calculated value of T (T1->T2) is 15usec.If another large external capacitance exists, this also influences to the RSSI response time. 1 1 VRSSI 70 V RSSI(T1) 6 RORSSI =15k 5 V RSSI VRSSI 70 T(time constant) = RORSSI x CEXT Cext V RSSI(T2) T1->T2 RORSSI =15k Cext Canother 5 V AF OUT How to Treat Unused Pin When the FM demodulator is not used, unused AF OUT pin (Pin10) is left open and unused QUAD IN pin (Pin9) is connected to power supply that is the same power supply voltage to V+ pin (Pin1). When the RSS is not used, unused RSSIOUT pin (Pin6) is left open. When the IF output is not used, it is recommended that unused IF OUT pins (Pin7 and 8) are left open. 6 C7 0.01u + IF OUT1 IF OUT2 RSSI OUT FM Demodulator NC NC 10 9 8 NC 7 NC 6 QUAD DET RSSI IF AMP RSSI 1 2 3 C1 0.01u C9 10u 4 C2 0.01u 5 C3 0.01u C8 0.01u IF Amplifier IF IN Ver.2011-09-26 -9- NJM2549 Noise and Sensitivity This document specify the following characteristics related to noise and sensitivity at low input signal level: S/N, -3dB limiting sensitivity, 12dB SINAD, and AMR. In general, the ways of improving these characteristics are: 1) To increase AF OUT output level of demodulated signal 2) To remove noise factor The way to increase AF OUT output level is already mentioned. As an example of how to remove noise factor, adding LPF at AF OUT is effective, especially to remove the factor of IF carrier signal and its harmonics involved in demodulated signal. The following characteristics show the effect of an additional LPF. An additional LPF is not connected: S+N -10 -30 40 AMR -40 30 N -50 10 -70 0 0 20 40 60 80 C4 100p 8 7 6 IF AMP 20 -60 C5 3p 9 V QUAD DET SINAD ( dB ) 50 SINAD T1 4CJH(10.7MHz) R2 2.4k 10 60 RSSI OUT + C6 82p C7 0.01u 70 -20 V Input impedance = 100k LPF = 30kHz 0 S+N, N, AMR ( dB ) AF OUT Audio Analyzer S+N, N, AMR, SINAD versus IF Input Level (Test Circuit 1) 1 2 3 C1 0.01u C9 10u RSSI C8 0.01u C2 0.01u 4 5 C3 0.01u R1 51 100 Zo=50 IF IN IF Input Level ( dBuV ) An additional LPF is connected: Ca 3300p Audio Analyzer Input impedance = 100k LPF = 30kHz S+N, N , AMR , SINAD versus IF Input Level (Test Circuit 8) + fc= 2 Ra 68k 3 1 Hz RaRbRcCaCbCc Rb 68k Cb 330p Rc 68k AF OUT Cc 1000p V 0 70 60 -20 50 -30 40 S/N AMR -40 30 -50 R2 2.4k C6 82p C7 0.01u 10 SINAD ( dB ) S+N, N, AMR ( dB ) SINAD 12dB 9 C5 3p C4 100p 8 7 6 QUAD DET IF AMP RSSI 20 N -60 12dB SINAD 0 20 40 60 IF Input Level ( dBuV ) 1 10 3dB liming sensitivity -70 0 80 100 2 C1 0.01u C9 10u C8 0.01u 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN Ver.2011-09-26 V T1 3dB S+N -10 RSSI OUT + - 10 - NJM2549 ! PARAMETER DESCRIPTION PARAMETER SYMBOL DESCRIPTION IF input signal IF IN Carrier frequency and input level of IF input signal. IF signal deviation fdev FM deviation of IF input signal. IF signal modulation fmod Frequency of base-band signal that FM modulates carrier to generate FM IF signal. Current consumption Iccq Total current through V+(Pin1) and QUAD IN (Pin9) under no IF signal input.. IF input/Output Gain GIF Difference between unbalanced input signal level at IF IN (Pin2) and output signal level at IF OUT (Pin7). f IF Difference of GIF at the two different IF frequency. IF amplifier input impedance RI IF Impedance between IF IN (Pin2) and IF DEC (Pin4). IF output level VO IF Output voltage of demodulated signal at IF OUT (Pin 7,8) Duty ratio of wave IF output DR IF Duty ratio of demodulated signal. IF output gain characteristics frequency IF output current I OIF Current at IF OUT (Pin7 or 8) under no IF signal input. Demodulated DC level VO DC DC output voltage at AF OUT (Pin10) under unmodulated IF carrier signal input. Demodulated signal level VO AC Output voltage of demodulated signal at AF OUT (Pin10) under the standard condition. Demodulated signal level of IF/3 VO AC2 12dB SINDA sensitivity 12dBS/N -3dB limiting sensitivity PI LIM Signal to noise ratio S/N AM rejection ratio AMR Total harmonic distortion THD AF output bias current IO AF Current at AF OUT (Pin10) under no IF signal input. Demodulated signal frequency characteristics fDET Flatness of demodulated signal level over a wide frequency range of base-band signal. Output voltage of demodulated signal at AF OUT (Pin10). IF carrier frequency is one third of the standard value. IF input signal level at 12dB SINAD (Signal-to-noise and distortion ratio, (S+N+D) / (N+D)) IF input signal level. AF OUT voltage of demodulated signal (S+N+D) is 3dB lower than the value in the stable region. S/N of demodulated signal. Ratio of AM demodulated signal level and FM demodulated signal level. The former is under AM IF input, and the latter is under FM IF input. Ratio of signal level between total harmonic factors involved in demodulated signal and base-band signal. RSSI output voltage V RSSI RSSI output voltage at RSSI OUT (Pin6). RSSI output resistance RO RSSI Resistance between RSSI (Pin6) and GND (Pin5). RSSI dynamic range DRSSI Range of IF input level while RSSI output voltage is proportional to the log of IF input signal level. RSSI response TRI /TFI Rise time / fall time of RSSI output voltage. Ver.2011-09-26 - 11 - NJM2549 ! ABSOLUTE MAXIMUM RATINGS PARAMETER (Ta=25C) SYMBOL RATINGS UNIT + Supply Voltage V 10 V Power Dissipation PD 300 mW Operating Temperature Topr - 40 to + 85 C Storage Temperature Tstg - 50 to + 125 C ! RECOMMENDED OPERATIONAL CONDITION PARAMETER Supply Voltage ! SYMBOL TEST CONDITIONS V+ (Ta=25C) MIN. TYP. MAX. UNIT 2.7 3 9 V ELECTRICAL CHARACTERISTICS (Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 80dBuV, fdev = 10kHz, fmod = 1kHz, unless otherwise noted) PARAMETER Current Consumption SYMBOL Iccq TEST CONDITIONS No Signal, Test Circuit 1 MIN. TYP. MAX. UNIT - 3 3.7 mA 70 75 80 dB -3 0 3 IF IF Input / Output Gain IF Output Gain Frequency Characteristics G IF f IF1 f IF2 IF Amplifier Input Resistance RI IF IF Output Level VO IF Duty Ratio of Wave IF Output DR IF IF Output Current Ver.2011-09-26 I OIF IF IN = 20dBuV , Test Circuit 4 The ratio from the gain at 10.7MHz to the gain at 1MHz, Test Circuit 4 The ratio from the gain at 10.7MHz to the gain at 15MHz, Test Circuit 4 2 - 4 pin Resistance, Test Circuit 3 RL = 15k, No Modulation, Test Circuit 4 RL = 15k, No Modulation, Test Circuit 4 No Signal, Test Circuit 4 dB -4 -1 2 8.5 10 11.5 k 350 425 500 mVpp 44 50 58 % 230 290 350 uA - 12 - NJM2549 PARAMETER SYMBOL TEST CONDITIONS MIN. TYP. MAX. UNIT DETECTION VO DC1 Demodulated DC Level VO DC2 VO DC3 IF IN = 10.62MHz, No Modulation, Test Circuit 1 IF IN = 10.7MHz, No Modulation, Test Circuit 1 IF IN = 10.83MHz, No Modulation, Test Circuit 1 - 0.1 0.3 0.8 1.1 1.4 2.7 2.9 - V Demodulated Signal Level VO AC1 Test Circuit 1 120 150 180 Demodulated Signal Level of IF/3 VO AC2 IF IN = 3.56667MHz, 100dBuV, Test Circuit 1 100 130 160 - 33 - - 22 - - 45 - - 45 - - 0.5 - % 160 205 250 uA - -2 - dB - 10 50 12dB SINAD Sensitivity 12dBS/N Test Circuit 1 - 3dB Limiting Sensitivity PI LIM Signal to Noise Ratio S/N AM Rejection Ratio AMR Total Harmonic Distortion THD AF Output pin Bias Current IO AF Demodulated Signal Frequency Characteristics fDET Measured at -3dB, Test Circuit 1 Ratio of S+N and N, Test Circuit 1 AM = 30%, Test Circuit 1 fdev = 30kHz, Test Circuit 1 No Signal, Test Circuit 4 fdev = 100kHz, fmod = 1kHz to 1MHz, Gain deflection, Test Circuit 6 mVrms dBuV dB RSSI V RSSI1 RSSI Output Voltage V RSSI2 V RSSI3 V RSSI4 RSSI Output Resistance RSSI Dynamic Range RO RSSI DRSSI No Signal, Test Circuit 1 IF IN = 45dBuV, Test Circuit 1 IF IN = 80dBuV, Test Circuit 1 IF IN = 100dBuV, Test Circuit 1 5 - 6 pin Resistance, Test Circuit 3 X = ( VRSSI3 - VRSSI2 ) / 35, D1 = 45 - ( VRSSI2 - VRSSI1 ) / X, D2 = 80 + ( VRSSI4 - VRSSI 3 ) / X, DRSSI = D2 - D1 Time taken for RSSI Output to change from 10% to 90% TRI after IF signal turns on. Test Circuit 7 RSSI Response Time taken for RSSI Output to change from 90% to 10% TFI after IF signal turns off. Test Circuit 7 The values shown in parenthesis are reference values. Ver.2011-09-26 mV 350 550 750 1.5 1.7 1.85 1.8 2 2.1 12 15 18 K - 60 - dB - 4 - V usec - 4 - - 13 - NJM2549 ! TEST CIRCUIT This test circuit allows the measurement of all parameters described in "ELECTRICAL CHARACTERISTICS". Test Circuit 1 (Detected Output: S-Curve) Audio Analyzer AF OUT Input impedance = 100k LPF = 30kHz V + T1 R2 2.4k C6 82p C7 0.01u 10 RSSI OUT 9 C5 3p V C4 100p 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN Test Circuit 2 (Detected Output: N-Curve, the Detected Output is reversed) Audio Analyzer AF OUT Input impedance = 100k LPF = 30kHz V + T1 C6 82p C7 0.01u 10 RSSI OUT R2 2.4k 9 8 C5 3p V C4 100p 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u 3 C2 0.01u R1 51 4 5 C3 0.01u T1:4CJH(Sample No.:080293006) Zo=50 IF IN Ver.2011-09-26 RSSI SAGAMI ELEC CO., LTD. (Japan) - 14 - NJM2549 Test Circuit 3 for Terminal Resistance 10 9 8 7 6 QUAD DET IF AMP 1 2 RSSI 3 4 5 Test Circuit 4 for IF Amplifier Oscilloscope A V T1 C7 0.01u C6 82p A 10 0.01uF + 15k Selector R2 2.4k 9 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN T1:4CJH(Sample No.:080293006) SAGAMI ELEC CO., LTD. (Japan) Ver.2011-09-26 - 15 - NJM2549 Test Circuit 5 for Demodulated Signal Frequency Characteristics (Detected Output: S-Curve) AF OUT Spectrum Analyzer FET Probe V + T1 R2 2.4k C6 82p C7 0.01u 10 RSSI OUT 9 C5 3p V C4 100p 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN Test Circuit 6 for Demodulated Signal Frequency Characteristics (Detected Output: N-Curve) AF OUT Spectrum Analyzer FET Probe V + T1 C6 82p C7 0.01u 10 RSSI OUT R2 360 9 8 C5 3p V C4 100p 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN T1:4CJH(Sample No.:080293006) SAGAMI ELEC CO., LTD. (Japan) Ver.2011-09-26 - 16 - NJM2549 Test Circuit 7 for RSSI Response AF OUT V + Oscilloscope T1 R2 2.4k C6 82p C7 0.01u 10 9 C5 3p C4 100p 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN Signal ON to OFF OFF to ON Test Circuit 8 for Demodulated signal (LPF is connected) Ca 3300p Audio Analyzer Input impedance = 100k LPF = 30kHz + fc= 1 Hz 2 3 RaRbRcCaCbCc Ra 68k Rb 68k Cb 330p Rc 68k AF OUT Cc 1000p V + RSSI OUT V T1 R2 2.4k C6 82p C7 0.01u 10 9 C5 3p C4 100p 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 Zo=50 IF IN T1:4CJH(Sample No.:080293006) SAGAMI ELEC CO., LTD. (Japan) Ver.2011-09-26 - 17 - NJM2549 ! TERMINAL FUNCTION (Ta = 25C, V+ = 3V, No signal) Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION 1 1 V+ -- Supply Voltage 5 1 1.95V 2pin: IF Amplifier Input 3,4pin: IF Decoupling An external decoupling capacitor is connected to enhance stability. The bandwidth of IF Amplifier can be adjusted. Large capacity: narrow IF Small capacity: wide IF -- Received Signal Strength Indicator Output Pin6 outputs DC level proportional to the log of pin2 input signal level. 1.25V FM IF Output This is a balanced output, and the capacitor for the phase-shifter is connected between QUAD IN and either of IF OUTs. The joining terminal changes the inclination. 7pin:N-Corve 8pin:S-Corve 2 2 3 4 IF IN IF DEC1 IF DEC2 3 10k 10k 4 50k 400uA 50k 5 1 70 6 RSSI 6 15k 5 1 70 7 8 7 IF OUT2 IF OUT1 70 8 300uA 300uA 5 Ver.2011-09-26 - 18 - NJM2549 Pin No. SYMBOL EQUIVARENT CIRCUIT VOLTAGE FUNCTION -- Quadrature Detector Input An external phase-shifting coil or discriminator is connected between IF OUT and pin9. Note that supply voltage should be the same as the voltage supplied to pin1. 1.05V Demodulated Signal Output Can output the wide range between ground level and supply voltage level. 1 9 QUAD IN 70 9 25uA 5 1 205uA 10 AF OUT 70 10 5 Ver.2011-09-26 - 19 - NJM2549 ! EVALUATION 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 V AF OUT + RSSI OUT T1 C7 0.01u R2 2.4k C6 82p 10 9 C5 3p C4 100p 8 7 6 QUAD DET IF AMP 1 2 C1 0.01u C9 10u C8 0.01u RSSI 3 C2 0.01u 4 5 C3 0.01u R1 51 IF IN List of Component Items Designation Value Items Designation Capacitor C1 0.01uF Resistor R1 Capacitor C2 0.01uF Resistor R2 Capacitor C3 0.01uF Capacitor C4 100pF Transformer T1 Capacitor C5 3pF Capacitor C6 82pF IC IC1 Capacitor C7 0.01uF Capacitor C8 0.01uF Capacitor C9 10uF Note: The IF transformer (T1) is prepared just for the use of NJM2549 evaluation board. Value 51 2.4k 4CJH NJM2549 Model: 4CJH(Sample No.:080293006), Supplier: SAGAMI ELEC CO., LTD. (Japan) Ver.2011-09-26 - 20 - NJM2549 PRINTED CIRCUIT BOARD C3 C5 C4 R1 C2 C1 IC1 NJM 2549 R2 C6 C8 C7 Circuit Side View Ground Side View + C9 Ver.2011-09-26 - 21 - NJM2549 ! TYPICAL CHARACTERISTICS [DC CHARACTERISTICS] (Test Circuit 1, Ta = 25C, V+ = 3V, No Signal, unless otherwise noted) Current Consumption versus Supply Voltage and Ambient Temperature Current Consumption versus Temperature and Supply Voltage 5 5 4 4 V+ = 9.0V, 3.0V 3 25C -40C 2 Iccq ( mA ) Iccq ( mA ) Ta= 85C 1 3 2.7V 2 1 0 0 0 2 4 6 8 -50 10 Supply Voltage V+ ( V ) 0 50 100 Ambient Temperature Ta ( C ) [IF AMP CHARACTERISTICS] (Test Circuit 4, Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 20dBuV, No Modulation, unless otherwise noted) IF AMP Gain versus IF Frequency and Terminal Capacitance IF AMP Gain versus IF Frequency ( Standard Circuit ) 100 100 Ta= -40C, 25C, 85C C1=C2=C3 =1uF 80 60 GIF ( dB ) GIF ( dB ) 80 40 60 10nF 3.3nF 1nF 40 20 20 0 0 0.1 1 10 0.1 100 85 85 80 80 Ta= 85C, 25C -40C 70 GIF ( dB ) GIF ( dB ) 100 IF AMP Gain versus Temperature and Supply Voltage IF AMP Gain versus Supply Voltage and Ambient Temperature V+ = 9.0V, 3.0V, 2.7V 75 70 65 65 2 4 6 8 Supply Voltage V + ( V ) Ver.2011-09-26 10 IF Input Frequency ( MHz ) IF Input Frequency ( MHz ) 75 1 10 -50 0 50 100 Ambient Temperature Ta ( C ) - 22 - NJM2549 IF Output Level versus Temperature and Supply Voltage 550 550 500 500 450 Ta= 85C 25C -40C 400 VO IF ( mVpp ) VO IF ( mVpp ) IF Output Level versus Supply Voltage and Ambient Temperature 350 450 V+ = 2.7V, 3.0V, 9.0V 400 350 300 300 2 4 6 8 10 -50 Supply Voltage V+ ( V ) IF Output Duty Ratio versus Supply Voltage and Ambient Temperature 50 100 IF Output Duty Ratio versus Temperature and Supply Voltage 60 60 Ta= -40C 55 85C 25C 50 V+ = 9.0V, 3.0V, 2.7V 55 DR IF ( % ) DR IF ( % ) 0 Ambient Temperature Ta ( C ) 45 50 45 40 40 2 4 6 8 10 -50 Supply Voltage V+ ( V ) 0 50 100 Ambient Temperature Ta ( C ) IF Output Current versus Supply Voltage and Ambient Temperature IF Output Current versus Temperature and Supply Voltage 400 400 350 350 V+= 9.0V, 3.0V, 2.7V 300 25C 250 IO IF ( uA ) IO IF ( uA ) Ta= -40C 300 250 -40C 200 200 2 4 6 Supply Voltage V+ ( V ) Ver.2011-09-26 8 10 -50 0 50 100 Ambient Temperature Ta ( C ) - 23 - NJM2549 [DEMODULATED CHARACTERISTICS (S- Curve)] (Test Circuit 1, Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 20dBuV, No Modulation, unless otherwise noted) Demodulated DC Level versus Frequency ( S-curve, BW:99MHz, Supply Voltage ) 5 10 4 8 3 6 2 VO DC ( V ) VO DC ( V ) Demodulated DC Level versus Frequency ( S-curve, BW:99MHz, Ambient Temperature ) Ta= -40C 25C 85C 1 V+= 9.0V 3.0V 2.7V 4 2 Ta= 0 0 1 10 1 100 10 Demodulated DC Level versus Frequency ( S-curve, BW:200kHz, Ambient Temperature ) Demodulated DC Level versus Frequency ( S-curve, BW:200kHz, Supply Voltage ) 5 5 4 V+=9.0V 3 VO DC ( V ) VO DC ( V ) 4 Ta= 85C 25C -40C 3 2 1 3.0V 2.7V 2 1 0 0 10.6 10.65 10.7 10.75 10.8 10.6 IF Input Frequency ( MHz ) 10.7 10.75 10.8 Demodulated DC Level versus Temperature ( S-curve, Supply Voltage ) 2.0 2.0 1.5 25C 1.0 -40C 0.5 V+= 9.0V 1.5 Ta= 85C VO DC ( V ) VO DC ( V ) 10.65 IF Input Frequency ( MHz ) Demodulated DC Level versus Supply Voltage ( S-curve, Ambient Temperature ) 3.0V, 2.7V 1.0 0.5 0.0 0.0 2 4 6 8 + Supply Voltage V ( V ) Ver.2011-09-26 100 IF Input Frequency ( MHz ) IF Input Frequency ( MHz ) 10 -50 0 50 100 Ambient Temperature Ta ( C ) - 24 - NJM2549 [DEMODULATED CHARACTERISTICS (N- Curve)] (Test Circuit 2, Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 20dBuV, No Modulation, unless otherwise noted) Demodulated DC Level versus Frequency ( N-curve, BW:99MHz, Ambient Temperature ) Demodulated DC Level versus Frequency ( N-curve, BW:99MHz, Supply Voltage ) 5 10 4 6 VO DC ( V ) 3 VO DC ( V ) 8 Ta= -40C 25C 85C 2 1 V+= 9.0V 3.0V 2.7V 4 2 0 0 1 10 100 1 10 IF Input Frequency ( MHz ) Demodulated DC Level versus Frequency ( N-curve, BW:200kHz, Ambient Temperature ) 5 4 4 Ta= 85C, 25C V+= 9.0V 3.0V 2.7V 3 V O DC ( V ) VO DC ( V ) Demodulated DC Level versus Frequency ( N-curve, BW:200kHz, Supply Voltage ) 5 3 2 -40C 2 1 1 0 0 10.6 10.65 10.7 10.75 10.6 10.8 IF Input Frequency ( MHz ) 10.7 10.75 10.8 Demodulated DC Level versus Temperature ( N-curve, Supply Voltage ) 2.0 2.0 1.5 1.5 Ta= 85C 25C -40C 1.0 0.5 V+= 9.0V VO DC ( V ) VO DC ( V ) 10.65 IF Input Frequency ( MHz ) Demodulated DC Level versus Supply Voltage ( N-curve, Ambient Temperature ) 1.0 3.0V, 2.7V 0.5 0.0 0.0 2 4 6 Supply Voltage V+ ( V ) Ver.2011-09-26 100 IF Input Frequency ( MHz ) 8 10 -50 0 50 100 Ambient Temperature Ta ( C ) - 25 - NJM2549 [DEMODULATED CHARACTERISTICS (AC Level)] (Test Circuit 1, Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 80dBuV, fdev = 10kHz, fmod = 1kHz, unless otherwise noted) S+N, N, AMR, SINAD versus IF Input Level (Test Circuit 1) S+N, N , AMR , SINAD versus IF Input Level (Test Circuit 8) -10 50 SINAD -30 40 -40 30 AMR N -50 20 -60 -70 0 20 40 60 80 SINAD 50 -30 40 AMR -40 10 -60 0 -70 20 10 N 0 0 100 20 40 60 80 100 IF Input Level ( dBuV ) Detuning Characteristic ( VOAC , THD, N-Curve ) 4 1000 3 S-Curve 2 1 1 S-Curve ( V ) 100 VOAC ( mVrms ) , THD ( % ) Circuit 1 VOAC V OAC ( mVrms ) , THD ( % ) 30 -50 Detuning Characteristic ( VOAC , THD, S-Curve ) 10 60 -20 IF Input Level ( dBuV ) 1000 70 SINAD ( dB ) 60 S+N Circuit 2 4 VOAC 100 10 3 N-Curve 1 2 N-Curve ( V ) -20 0 S+N, N, AMR ( dB ) S+N, N, AMR ( dB ) -10 70 SINAD ( dB ) S+N 0 1 THD THD 0.1 0 10.55 10.6 10.65 10.7 10.75 10.8 10.85 IF Input Frequency ( MHz ) 0.1 0 10.55 10.6 10.65 10.7 10.75 10.8 10.85 IF Input Frequency ( MHz ) Demodulated Signal Level versus FM Modulation Frequency 175 Circuit 6 fdev= 100kHz 150 V O AC ( mVrms ) 125 100 75 50 25 Circuit 5 fdev= 10kHz 0 1 10 100 1000 10000 FM Modulation Frequency fmod ( kHz ) Ver.2011-09-26 - 26 - NJM2549 Demodulated Signal Level versus Supply Voltage and Ambient Temperature Demodulated Signal Level versus Temperature and Supply Voltage 200 200 180 180 VO AC ( mVrms ) 160 140 V+= 9.0V 160 VO AC ( mVrms ) Ta= 85C 25C -40C 3.0V, 2.7V 140 120 120 100 100 2 4 6 8 10 -50 Supply Voltage V+ ( V ) AF Output pin Bias Current versus Supply Voltage and Ambient Temperature 50 100 AF Output pin Bias Current versus Temperature and Supply Voltage 350 350 300 250 V+ = 9.0V 300 Ta= 85C IO AF ( uA ) IO AF ( uA ) 0 Ambient Temperature Ta ( C ) 25C 200 250 3.0V 2.7V 200 -40C 150 150 100 100 2 4 6 8 10 Supply Voltage V+ ( V ) -50 0 50 100 Ambient Temperature Ta ( C ) Demodulated DC Level versus Frequency and R2 3 R2= 4.7k 2.4k 1.2k VO DC ( V ) 2 680 360 180 1 0 10.6 10.65 10.7 10.75 10.8 IF Input Frequency ( MHz ) Ver.2011-09-26 - 27 - NJM2549 [RSSI CHARACTERISTICS] (Test Circuit 1, Ta = 25C, V+ = 3V, IF IN = 10.7MHz / 80dBuV, fdev = 10kHz, fmod = 1kHz, unless otherwise noted) RSSI Output versus IF Input Level and Ambient Temperature 2.5 RSSI Output versus IF Input Level and Supply Voltage 2.5 Ta= 85C 25C -40C 2.0 V+= 9.0V 2.0 3.0V, 2.7V 1.5 VRSSI ( V ) VRSSI ( V ) 1.5 1.0 0.5 1.0 0.5 0.0 0.0 0 20 40 60 80 100 0 IF Input Level ( dBuV ) 20 40 60 80 100 IF Input Level ( dBuV ) RSSI Output versus Temperature and IF Input Level RSSI Output versus Supply Voltage and IF Input Level 2.5 2.5 IF IN= 100dBuV IF IN= 100dBuV 2.0 2.0 80dBuV 80dBuV 1.5 1.0 45dBuV VRSSI ( V ) VRSSI ( V ) 1.5 1.0 45dBuV 0.5 0.5 No input signal 0.0 2 4 6 8 10 Supply Voltage V+ ( V ) No input signal 0.0 -50 0 50 100 Ambient Temperature Ta ( C ) RSSI Output versus Supply Voltage Frequency and IF Input Level 2.5 IF IN= 100dBuV VRSSI ( V ) 2.0 80dBuV 1.5 1.0 45dBuV 0.5 No input signal 0.0 0.1 1 10 100 [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. IF Input Frequency ( MHz ) Ver.2011-09-26 - 28 - Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: NJR: NJM2549RB2-TE2