ML3356 Wideband FSK Receiver Legacy Device: Motorola MC3356 P DIP 20 = RP PLASTIC PACKAGE CASE 738 The ML3356 includes Oscillator, Mixer, Limiting IF Amplifier, Quadrature Detector, Audio Buffer, Squelch, Meter Drive, Squelch Status output, and Data Shaper comparator. The ML3356 is designed for use in digital data communciations equipment. • Data Rates up to 500 kilobaud • Excellent Sensitivity: – 3 dB Limiting Sensitivity 30 µVrms @ 100 MHz • Highly Versatile, Full Function Device, yet Few External Parts are Required • Down Converter Can be Used Independently — Similar to NE602 • Operating Temperature Range TA = –40° to +85°C SO 20W = -6P PLASTIC PACKAGE CASE 751D (SO–20L) PACKAGE MOTOROLA LANSDALE P DIP 20 SO 20W MC3356P MC3356DW ML3356RP ML3356-6P Note: Lansdale lead free (Pb) product, as it becomes available, will be identified by a part number prefix change from ML to MLE. Figure 1. Representative Block Diagram RF VCC PIN CONNECTIONS RF Ground 1 20 2 19 3 18 OSC 4 Mixer Data Shaping Comparator + 5 Ceramic Filter 6 7 – Ground Data Output VCC 16 15 Comparator – + Meter Current Limiter 17 RF Input 14 Squelch Status Hysteresis Buffer 8 13 9 12 10 11 Squelch Adjust (Meter) RF Ground 1 20 RF Input OSC Emitter 2 19 Ground OSC Collector 3 18 Data Output RF VCC 4 17 + Comparator Mixer Output 5 16 – Comparator IF VCC 6 15 Squelch Status Limiter Input 7 14 Squelch Control Limiter Bias 8 13 Buffered Output Limiter Bias 9 12 Demodulator Filter Quad Bias 10 11 Quad Input Quadrature Detector Tank VCC Page 1 of 9 www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. MAXIMUM RATINGS Rating Power Supply Voltage Symbol Value Unit VCC(max) 15 Vdc VCC 3.0 to 9.0 Vdc RF VCC 3.0 to 12.0 Vdc Operating Power Supply Voltage Range (Pins 6, 10) Operating RF Supply Voltage Range (Pin 4) Junction Temperature TJ 150 °C Operating Ambient Temperature Range TA – 40 to + 85 °C Storage Temperature Range Tstg – 65 to + 150 °C Power Dissipation, Package Rating PD 1.25 W ELECTRICAL CHARACTERISTICS (VCC = 5.0 Vdc, fo = 100 MHz, fosc = 110.7 MHz, ∆f = ±75 kHz, fmod = 1.0 kHz, 50 Ω source, TA = 25°C, test circuit of Figure 2, unless otherwise noted.) Characteristics Min Typ Max Unit Drain Current Total, RF VCC and VCC – 20 25 mAdc Input for – 3 dB limiting – 30 – µVrms – 60 – µVrms 2.5 – – v/v Mixer Input Resistance, 100 MHz – 260 – Ω Mixer Input Capacitance, 100 MHz – 5.0 – pF Mixer/Oscillator Frequency Range (Note 1) – 0.2 to 150 – MHz IF/Quadrature Detector Frequency Range (Note 1) – 0.2 to 50 – MHz AM Rejection (30% AM, RF Vin = 1.0 mVrms) – 50 – dB Demodulator Output, Pin 13 – 0.5 – Vrms Meter Drive – 7.0 – µA/dB Squelch Threshold – 0.8 – Vdc Input for 50 dB quieting ( S N+ N ) Mixer Voltage Gain, Pin 20 to Pin 5 NOTE: 1. Not taken in Test Circuit of Figure 2; new component values required. Figure 2. Test Circuit Squelch Status Demod Out Data Output 100 MHz RF Input 3.0 k 0.1 0.01 390 k 20 RF Input L1 – 110.7 MHz, 0.4 µH L1 – 7T #22, 3/16 Form L1 – w/slug & can L2 – 10.7 MHz, 1.5 µH L2 – 20T #30, 3/16 Form L2 – w/slug & can T1 – muRata T1 – SFE10.7 MA5–Z or KYOCERA T1 – KBF10.7MN–MA 3.3 k 18 k 10 k 0.01 51 19 18 Ground Data Output 3.3 k 17 Comp(+) 16 15 Comp(–) 14 Squelch Status Squelch Control 470 pF 18 k 13 12 11 Demod Out Demod Filter Quad Input 150 pF L2 RF Gnd OSC EM. OSC COL. 1 2 3 RF VCC 4 Mixer Out Limiter Input VCC 6 5 Limiter Bias 7 8 0.01 5.6 pF Limiter Bias 9 Quad Bias 10 0.01 330 15 pF VCC L1 330 Page 2 of 9 130 k 47 k 47 k T1 0.01 5 Vdc www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. Figure 3. Output Components of Signal, Noise, and Distortion Figure 4. Meter Current versus Signal Input 10 700 S+N+D METER CURRENT, PIN 14 (µA) RELATIVE OUTPUT (dB) 0 fO = 100 MHz fm = 1.0 kHz ∆f = ± 75 kHz –10 –20 –30 N+D –40 N –50 –60 0.01 0.1 1.0 600 500 400 300 200 100 0 0.010 10 INPUT (mVrms) GENERAL DESCRIPTION This device is intended for single and double conversion VHF receiver systems, primarily for FSK data transmission up to 500 K baud (250 kHz). It contains an oscillator, mixer, limiting IF, quadrature detector, signal strength meter drive, and data shaping amplifier. The oscillator is a common base Colpitts type which can be crystal controlled, as shown in Figure 1, or L–C controlled as shown in figure 8. At higher VCC, it has been operated as high as 200 MHz. A mixer/oscillator voltage gain of 2 up to approximately 150 MHz, is readily achievable. The mixer functions well from an input signal of 10 µVrms, below which the squelch is unpredictable, up to about 10 mVrms, before any evidence of overload. Operation up to 1.0 Vrms input is permitted, but non–linearity of the meter output is incurred, and some oscillator pulling is suspected. The AM rejection above 10 mVrms is degraded. The limiting IF is a high frequency type, capable of being operated up to 50 MHz. It is expected to be used at 10.7 MHz in most cases, due to the availability of standard ceramic resonators. The quadrature detector is internally coupled to the IF, and a 5.0 pF quadrature capacitor is internally provided. The –3dB limiting sensitivity of the IF itself is approximately 50 µV (at Pin 7), and the IF can accept signals up to 1.0 Vrms without distortion or change of detector quiescent DC level. The IF is unusual in that each of the last 5 stages of the 6 state limiter contains a signal strength sensitive, current sinking device. These are parallel connected and buffered to produce a signal strength meter drive which is fairly linear for IF input signals of 10 µV to 100 mVrms (see Figure 4). A simple squelch arrangement is provided whereby the meter current flowing through the meter load resistance flips a comparator at about 0.8 Vdc above ground. The signal strength at which this occurs can be adjusted by changing the Page 3 of 9 0.1 1.0 10 PIN 20 INPUT (mVrms) 100 1000 meter load resistor. The comparator (+) input and output are available to permit control of hysteresis. Good positive action can be obtained for IF input signals of above 30 µVrms. The 130 kΩ resistor shown in the test circuit provides a small amount of hysteresis. Its connection between the 3.3k resistor to ground and the 3.0 k pot, permits adjustment of squelch level without changing the amount of hysteresis. The squelch is internally connected to both the quadrature detector and the data shaper. The quadrature detector output, when squelched, goes to a DC level approximately equal to the zero signal level unsquelched. The squelch causes the data shaper to produce a high (VCC) output. The data shaper is a complete ‘‘floating’’ comparator, with back to back diodes across its inputs. The output of the quadrature detector can be fed directly to either input of this amplifier to produce an output that is either at VCC or VEE, depending upon the received frequency. The impedance of the biasing can be varied to produce an amplifier which “follows” frequency detuning to some degree, to prevent data pulse width changes. When the data shaper is driven directly from the demodulator output, Pin 13, there may be distortion at Pin 13 due to the diodes, but this is not important in the data application. A useful note in relating high/low input frequency to logic state: low IF frequency corresponds to low demodulator output. If the oscillator is above the incoming RF frequency, then high RF frequency will produce a logic low (input to (+) input of Data Shaper as shown in Figures 1 and 2). APPLICATION NOTES The ML3356 is a high frequency/high gain receiver that requires following certain layout techniques in designing a stable circuit configuration. The objective is to minimize or eliminate, if possible, any unwanted feedback. www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. Legacy Applications Information Figure 5. Application with Fixed Bias on Data Shaper Car. Det. Out Data Out 5.0 V 0 V or 4.0 V 18 k 3.3 k 15 k 130 k RF In 1:2 10 k 0.01 3.0 k 20 19 18 RF Input Ground Data Output 470 pF 0.1 10 k 3.3 k 390 k 17 16 Comp(+) Comp(–) 15 Squelch Status 18 k 14 13 12 11 Squelch Control Demod Out Demod Filter Quad Input 150 pF ML3356 5.0 V RF Gnd OSC EM. 1 2 15 pF OSC COL. RF VCC 4 3 5.6 pF fO Mixer Out 5 0.01 4.0 V Limiter Input Limiter Bias 7 0.1 0.01 330 Limiter Bias 8 330 0.01 Bead + 5.0 to + 12 V VCC 6 9 Quad Bias 10 0.01 0.01 Bead 0.1 Cer. Fil. 10.7 MHz 180 82 APPLICATION NOTES (continued) Shielding, which includes the placement of input and output components, is important in minimizing electrostatic or electromagnetic coupling. The ML3356 has its pin connections such that the circuit designer can place the critical input and output circuits on opposite ends of the chip. Shielding is normally required for inductors in tuned circuits. The ML3356 has a separate VCC and ground for the RF and IF sections which allows good external circuit isolation by minimizing common ground paths. Note that the circuits of Figures 1 and 2 have RF, Oscillator, and IF circuits predominantly referenced to the plus supply rails. Figure 5, on the other hand, shows a suitable means of ground referencing. The two methods produce identical results when carefully executed. It is important to treat Pin 19 as a ground node for either approach. The RF input should be ‘‘grounded’’ to Pin 1 and then the input and the mixer/oscillator grounds (or RF VCC bypasses) should be connected by a Page 4 of 9 low inductance path to Pin 19. IF and detector sections should also have their bypasses returned by a separate path to Pin 19. VCC and RF VCC can be decoupled to minimize feedback, although the configuration of Figure 2 shows a successful implementation on a common 5.0 V supply. Once again, the message is: define a supply node and a ground node and return each section to those nodes by separate, low impedance paths. The test circuit of Figure 2 has a 3 dB limiting level of 30 µV which can be lowered 6 db by a 1:2 untuned transformer at the input as shown in Figures 5 and 6. For applications that require additional sensitivity, an RF amplifier can be added, but with no greater than 20 db gain. This will give a 2.0 to 2.5 µV sensitivity and any additional gain will reduce receiver dynamic range without improving its sensitivity. Although the test circuit operates at 5.0 V, the mixer/oscillator optimum performance is at 8.0 V to 12 V. A minimum of 8.0 V is recommended in high frequency applications (above 150 MHz), or in PLL applications where the oscillator drives a prescaler. www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. Legacy Applications Information Figure 6. Application with Self–Adjusting Bias on Data Shaper Data Out 5.0 V Car. Det. Out 0 V or 4.0 V 130 k 3.3 k 1 15 k 47 k RF In 47 k 10 k 0.01 3.3 k 1:2 470 k 20 19 18 RF Input Ground Data Output 470 pF 0.1 470 pF 17 Comp(+) 16 15 Comp(–) Squelch Status 18 k 0.1 14 Squelch Control 13 12 11 Demod Out Demod Filter Quad Input f = 10.7 150 pF 1.5 µH APPLICATION NOTES (continued) Depending on the external circuit, inverted or noninverted data is available at Pin 18. Inverted data makes the higher frequency in the FSK signal a “one” when the local oscillator is above the incoming RF. Figure 5 schematic shows the comparator with hysteresis. In this circuit the DC reference voltage at Pin 17 is about the same as the demodulated output voltage (Pin 13) when no signal is present. This type circuit is preferred for systems where the data rates can drop to zero. Some systems have a low frequency limit on the data rate, such as systems using the MC3850 ACIA that has a start or Page 5 of 9 stop bit. This defines the low frequency limit that can appear in the data stream. Figure 5 circuit can then be changed to a circuit configuration as shown in Figure 6. In Figure 6 the reference voltage for the comparator is derived from the demodulator output through a low pass circuit where τ is much lower than the lowest frequency data rate. This and similar circuits will compensate for small tuning changes (or drift) in the quadrature detector. Squelch status (Pin 15) goes high (squelch off) when the input signal becomes greater than some preset level set by the resistance between Pin 14 and ground. Hysteresis is added to the circuit externally by the resistance from Pin 14 to Pin 15. www.lansdale.com Issue A Page 6 of 9 www.lansdale.com 19 8 9 7 6 1 20 2 3 4 13 1.0 k 2 14 135 59 5.0 k 1.0 k 1.0 k 58 15 1.0 k 5.0 k 1. 0 k 3 1.0 k 135 5 9 60 1.0 k 330 6 57 17 1.0 k 5.0 k 1.0 k 16 4 13 5 18 1.0 k 3 30 7 61 19 1.0 k 10 8 5 56 135 20 1.0 k 20 pF 1.0 k 1.0 k 62 14 55 21 1.0 k 12 11 5.0 k 135 22 50 k 66 71 63 1 .0 k 69 64 72 1.0 k 1.0 k 68 20 k 20 k 24 67 135 10 k 54 23 1.0 k 50 k 1.0 k 65 5.0 k 25 20 k 73 10 k 27 70 26 15 10 k 28 10 k 10 k 35 75 5.0 pF 11 Figure 7. Internal Schematic 10 k 31 1.0 k 76 29 500 32 53 1.0 k 33 135 81 77 2.0 k 30 10 83 17 10 k 34 84 85 87 86 36 37 41 42 40 89 38 78 2.0 k 43 44 91 52 34 45 46 13 12 82 51 39 92 135 1.0 k 79 2.0 k 50 225 48 90 16 93 80 2.0 k 49 47 2.5 k 94 18 ML3356 LANSDALE Semiconductor, Inc. Issue A ML3356 LANSDALE Semiconductor, Inc. RF IN P1 C6 15pF C5 47pF dataout C4 1nF R1 R2 10k 330k L2 1uH R3 18k 130k R5 3.3k R11 10k 40% C12 R12 .1uF U1 R14 15k R15 18k L3 1uH C10 .01uF C8 470pF C7 150pF C9 .01uF V2 5V +V U2 C20 .1uF R8 10k R7 2.7k C19 .1uF V4 5V +V J2 SPI Loop Filter cardet P20 rfin P19 gnd P18 dataout P17 comp+ P16 compP15 sqstatus P14 sqctrl P13 bufout P12 demfil P11 quadin R13 3.3k C1 47pf 330 C11 .01uF R17 cerfil U3 R10 10k C2 10pf +V gnd P1 oscemit P2 osccol P3 rfvcc P4 mixout P5 ifvcc P6 limin 7 limbias P P8 limbias P9 quadbias P10 L1 1uH R16 330 C21 10pF D2 MV209 R9 3.3k C16 27pF P16Vdd P15 phsV P14phsR P13PDout P12Vss P11 LD P10 Fv P9 Fr VCO C3 .1uF V3 5V C15 .1uF +V XTAL2 1.000MHZ 1Meg R6 C17 27pF oscin 1 oscoutP P2 REFoutP3 Fin P4 Din P5 enb P6 clk P7 DoutP8 R4 10k 5V V1 C18 1nF MC145170 ML3356_ Figure 8 Typical Application using a PLL with L.O. less than 185 MHz. Figure 8 shows a typical application using the MC145170/ML145170 PLL device. The PLL allows the L.O. to be used as a VCO thus allowing multi - channel operation. Page 7 of 9 www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. RF IN P1 C6 15pF C5 47pF dataout C4 1nF R1 R2 10k 330k L2 1uH R3 18k 130k R5 3.3k R11 10k 40% C12 R12 .1uF U1 R14 15k R15 18k L3 1uH C10 .01uF C8 470pF C7 150pF C9 .01uF V2 5V +V U2 C20 .1uF R8 10k R7 2.7k C19 .1uF V4 5V +V J2 SPI Loop Filter cardet P20 rfin P19 gnd P18 dataout P17 comp+ P16 compP15 sqstatus P14 sqctrl P13 bufout P12 demfil P11 quadin R13 3.3k C1 47pf 330 C11 .01uF R17 cerfil U4 R10 10k C2 10pf +V gnd P1 oscemit P2 osccol P3 rfvcc P4 mixout P5 ifvcc P6 limin P7 limbias P 8 limbias P9 quadbias P10 L1 1uH R16 330 C21 10pF D2 MV209 R9 3.3k C16 27pF P16 phsR P15 phsP P14 Fout P13 BISW P 1 2 FC P 1 1 LE P10data P9 clk C3 .1uF V3 5V C15 .1uF +V XTAL2 1.000MHZ 1Meg C17R6 27pF Oscin P1 Oscout P2 Vp P3 Vcc P4 DoP5 gnd P6 LD P 7 Fin P8 VCO R4 10k 5V V1 C18 1nF ML12202 ML3356_ Figure 9 Typical Application using a PLL with L.O. greater than 185 MHz. Figure 9 shows a typical application using the ML12202 PLL device. The PLL (ML12202) allows the L.O. to be used as a VCO thus allowing multli-channel operation. Page 8 of 9 www.lansdale.com Issue A ML3356 LANSDALE Semiconductor, Inc. OUTLINE DIMENSIONS P DIP 20 = RP (ML3356RP) PLASTIC PACKAGE CASE 738–03 –A – 20 11 1 10 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: INCH. 3. DIMENSION “L” TO CENTER OF LEAD WHEN FORMED PARALLEL. 4. DIMENSION “B” DOES NOT INCLUDE MOLD FLASH. 5. 738–02 OBSOLETE, NEW STANDARD 738–03. B C –T– L K SEATING PLANE M E G N F J 20 PL 0.25 (0.010) D 20 PL 0.25 (0.010) M T A M SO 20 = -6P (ML3356-6P) PLASTIC PACKAGE CASE 751D–03 (SO–20L) 11 1 10 –B – 0.25 (0.010) P M B M 10 PL G R X 45° C –T– SEATING PLANE M K D 20 PL 0.25 (0.010) M T B S A F T B M MILLIMETERS MIN MAX 25.66 27.17 6.10 6.60 3.81 4.57 0.39 0.55 1.27 BSC 1.27 1.77 2.54 BSC 0.21 0.38 2.80 3.55 7.62 BSC 0° 15° 1.01 0.51 INCHES MIN MAX 1.010 1.070 0.240 0.260 0.150 0.180 0.015 0.022 0.050 BSC 0.050 0.070 0.100 BSC 0.008 0.015 0.110 0.140 0.300 BSC 0° 15° 0.020 0.040 NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSION A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. 751D–01, AND –02 OBSOLETE, NEW STANDARD 751D–03. –A – 20 M DIM A B C D E F G J K L M N J S DIM A B C D F G J K M P R MILLIMETERS MIN MAX 12.65 12.95 7.40 7.60 2.35 2.65 0.35 0.49 0.50 0.90 1.27 BSC 0.25 0.32 0.10 0.25 0° 7° 10.05 10.55 0.25 0.75 INCHES MIN MAX 0.499 0.510 0.292 0.299 0.093 0.104 0.014 0.019 0.020 0.035 0.050 BSC 0.010 0.012 0.004 0.009 7° 0° 0.395 0.415 0.010 0.029 Lansdale Semiconductor reserves the right to make changes without further notice to any products herein to improve reliability, function or design. Lansdale does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. “Typical” parameters which may be provided in Lansdale data sheets and/or specifications can vary in different applications, and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by the customer’s technical experts. Lansdale Semiconductor is a registered trademark of Lansdale Semiconductor, Inc. Page 9 of 9 www.lansdale.com Issue A