PIN CONNECTIONS. 1st LO Base. Varicap C. 1st LO Emitter. Varicap A. 1st LO Out. 1st Mixer In 1. 1st Mixer In 2. 2nd LO Emitter.

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1 Order this document by MC/D The MC/MC are the second generation of single chip, dual conversion FM communications receivers developed by Motorola. Major improvements in signal handling, RSSI and first oscillator operation have been made. In addition, recovered audio distortion and audio drive have improved. Using Motorola s MOSAIC. process, these receivers offer low noise, high gain and stability over a wide operating voltage range. Both the MC and MC include a Colpitts oscillator, VCO tuning diode, low noise first and second mixer and LO, high gain limiting IF, and RSSI. The MC is designed for use with an LC quadrature detector and has an uncommitted op amp that can be used either for an RSSI buffer or as a data comparator. The MC can be used with either a ceramic discriminator or an LC quad coil and the op amp is internally connected for a voltage buffered RSSI output. These devices can be used as stand alone VHF receivers or as the lower IF of a triple conversion system. Applications include cordless telephones, short range data links, walkie talkies, low cost land mobile, amateur radio receivers, baby monitors and scanners. Complete Dual Conversion FM Receiver Antenna to Audio Output Input Frequency Range MHz Voltage Buffered RSSI with db of Usable Range Low Voltage Operation. to. Vdc ( Cell NiCad Supply) Low Current Drain. ma Typ Low Impedance Audio Output < Ω VHF Colpitts First LO for Crystal or VCO Operation Isolated Tuning Diode Buffered First LO Output to Drive CMOS PLL Synthesizer DUAL CONVERSION NARROWBAND FM RECEIVERS Device MCP MCDW MCDW ORDERING INFORMATION Operating Temperature Range TA = to 8 C P SUFFIX PLASTIC PACKAGE CASE DW SUFFIX PLASTIC PACKAGE CASE E (SO L) Package Plastic DIP SO L SO L MC PIN CONNECTIONS MC st LO Base st LO Varicap Varicap C st LO Base st LO Varicap Varicap C st LO Emitter Varicap A st LO Emitter Varicap A st LO Out st Mixer In st Mixer In st LO Out st Mixer In st Mixer In nd LO Emitter nd LO Base nd LO st Mixer Out nd LO Emitter nd LO Base nd LO st Mixer Out nd Mixer Out 8 AF 8 nd Mixer In Audio Out nd Mixer Out 8 AF 8 nd Mixer In Audio Out Limiter In Decouple Limiter Demod Op Amp Out Op Amp In Limiter In Decouple Limiter Demod Buffered RSSI Output Op Amp In Decouple Op Amp In Decouple Limiter Output RSSI Quad Coil RSSI Quad Input Each device contains active transistors. Motorola, Inc. 8 Rev

2 MAXIMUM RATINGS Rating Pin Symbol Value Unit Power Supply Voltage, (max). Vdc RF Input Voltage RFin. Vrms Junction Temperature TJ C Storage Temperature Range Tstg to C RECOMMENDED OPERATING CONDITIONS Rating Pin Symbol Value Unit Power Supply Voltage,. to. Vdc Maximum st IF fif MHz Maximum nd IF fif. MHz Ambient Temperature Range TA to 8 C ELECTRICAL CHARACTERISTICS (TA = C, =. Vdc, fo =. MHz, fmod =. khz, Deviation = ±. khz, fst LO = MHz, fnd LO =. MHz, IF =. MHz, IF =, unless otherwise noted. All measurements performed in the test circuit of Figure.) Characteristic Condition Symbol Min Typ Max Unit Total Drain Current No Input Signal ICC.. madc Sensitivity (Input for db SINAD) Matched Input VSIN. µvrms Recovered Audio VRF =. mv AFO mvrms MC MC Limiter Output Level VLIM mvrms (Pin, MC) st Mixer Conversion Gain VRF = dbm MXgain db nd Mixer Conversion Gain VRF = dbm MXgain db First LO Buffered Output VLO mvrms Total Harmonic Distortion VRF = dbm THD.. % Demodulator Bandwidth BW khz RSSI Dynamic Range RSSI db First Mixer rd Order Intercept TOIMix dbm (Input) Matched Unmatched Second Mixer rd Order Matched TOIMix dbm Intercept (RF Input) Input First LO Buffer Output Resistance RLO Ω First Mixer Parallel Input Resistance R Ω First Mixer Parallel Input Capacitance C. pf First Mixer Output Impedance ZO Ω Second Mixer Input Impedance ZI. kω Second Mixer Output Impedance ZO.8 kω Detector Output Impedance ZO Ω

3 TEST CIRCUIT INFORMATION Although the MC can be operated with a ceramic discriminator, the recovered audio measurements for both the MC and MC are made with an LC quadrature detector. The typical recovered audio will depend on the external circuit; either the Q of the quad coil, or the RC matching network for the ceramic discriminator. On the MC, an external capacitor between Pins and can be used with a quad coil for slightly higher recovered audio. See Figures through for additional information. Since adding a matching circuit to the RF input increases the signal level to the mixer, the third order intercept (TOI) point is better with an unmatched input ( Ω from Pin to Pin ). Typical values for both have been included in the Electrical Characterization Table. TOI measurements were taken at the pins with a high impedance probe/spectrum analyzer system. The first mixer input impedance was measured at the pin with a network analyzer. Figure a. MC Test Circuit. k.8 µh. MHz Xtal. k. p. p st LO Varicap.. µh. Figure. pf 8 p RF Input p p nd LO. MHz. MHz Xtal 8 Limiter Demod AF 8 8. k k k Quad Coil Figure b. MC Quad Detector Test Circuit Demod AF Limiter k k Quad Coil

4 Figure. Supply Current versus Supply Voltage. Figure. RSSI Output versus RF Input I CC, SUPPLY CURRENT (ma)..... RFin =. MHz fmod =. khz fdev = ±. khz RSSI OUTPUT (mvdc, Pin ) 8 =. V RFin =. MHz fmod =. khz fdev = ±. khz , SUPPLY VOLTAGE (V) 8 RF INPUT (dbm) C P, EQUIVALENT PARALLEL CAPACITANCE (pf).. Figure. Varactor Capacitance, Resistance versus Bias Voltage CP, f = MHz CP, f = MHz RP, f = MHz RP, f = MHz VB, VARACTOR BIAS VOLTAGE, VPin to VPin (Vdc) R P, EQUIVALENT PARALLEL RESISTANCE (k Ω ) f, FREQUENCY (MHz) Figure. Oscillator Frequency versus Varactor Bias p p. p st LO Varicap. µh p. MΩ. µf..... VB, VARACTOR BIAS VOLTAGE (Vdc) V B POWER (dbm) Figure. Signal Levels versus RF Input Second Mixer Output First Mixer Output First Mixer Input Second Mixer Input 8 RFin, RF INPUT (dbm) SN, N, AND AMR (db) Figure. Signal Noise, Noise, and AM Rejection versus Input Power =. Vdc RFin =. MHz fmod =. khz fdev = ±. khz S N S N % AM RFin, RF INPUT (dbm) N

5 Figure 8. Op Amp Gain and Phase versus Frequency 8 Figure. First Mixer Third Order Intermodulation (Unmatched Input) A V, GAIN (db) Gain Phase φ, EXCESS PHASE (DEGREES) MIXER OUTPUT (db) 8 Desired Products rd Order Intermod Products k k. M M f, FREQUENCY (Hz) 8 8 RF INPUT (dbm) RA, RECOVERED AUDIO (mv pp ) ±. Figure. Recovered Audio versus Deviation for MC R Quad Coil Toko MC 88Z R = 8 kω R = kω R = kω ±. ±. ±. ±. fdev, DEVIATION (khz) THD, TOTAL HARMONIC DISTORTION (%) R Figure. Distortion versus Deviation for MC Quad Coil Toko MC 88Z. R = kω. ±. ±. ±. ±. ±. fdev, DEVIATION (khz) R = 8 kω R = kω RA, RECOVERED AUDIO (mv pp ) 8 ±. C Figure. Recovered Audio versus Deviation for MC R murata Resonator CDBC R =. kω C = pf R =. kω C = pf ±. ±. ±. ±. ± 8. ±. fdev, DEVIATION (khz) R = C = pf THD, TOTAL HARMONIC DISTORTION (%) C Figure. Distortion versus Deviation for MC R murata Resonator CDBC R = C = pf R =. kω C = pf R =. kω C = pf ±. ±. ±. ±. ±. ± 8. ±. fdev, DEVIATION (khz)

6 CIRCUIT DESCRIPTION The MC/ are complete dual conversion receivers. They include two local oscillators, two mixers, a limiting IF amplifier and detector, and an op amp. Both provide a voltage buffered RSSI with db of usable range, isolated tuning diode and buffered LO output for PLL operation, and a separate pin for the first mixer and LO. Improvements have been made in the temperature performance of both the recovered audio and the RSSI. Two separate lines enable the first LO and mixer to continue running while the rest of the circuit is powered down. They also isolate the RF from the rest of the internal circuit. Local Oscillators The local oscillators are grounded collector Colpitts, which can be easily crystal controlled or VCO controlled with the on board varactor and external PLL. The first LO transistor is internally biased, but the emitter is pinned out and IQ can be increased for high frequency or VCO operation. The collector is not pinned out, so for crystal operation, the LO is generally limited to rd overtone crystal frequencies; typically around MHz. For higher frequency operation, the LO can be provided externally as shown in Figure. Buffer An amplifier on the st LO output converts the single ended LO output to a differential signal to drive the mixer. Capacitive coupling between the LO and the amplifier minimizes the effects of the change in oscillator current on the mixer. Buffered LO output is pinned out at Pin for use with a PLL, with a typical output voltage of mvpp at =. V and with a. k resistor from Pin to ground. As seen in Figure, the buffered LO output varies with the supply voltage and a smaller external resistor may be needed for low voltage operation. The LO buffer operates up to MHz, typically. Above MHz, the output at Pin rolls off at approximately. db per octave. Since most PLLs require about mvpp drive, an external amplifier may be required. OUTPUT (mv pp ) Figure. Buffered LO Output Voltage versus Supply Voltage RPin =. kω RPin =. kω Mixers The first and second mixer are of similar design. Both are double balanced to suppress the LO and input frequencies to give only the sum and difference frequencies out. This configuration typically provides to db of LO suppression. New design techniques provide improved mixer linearity and third order intercept without increased noise. The gain on the output of the st mixer starts to roll off at about MHz, so this receiver could be used with a MHz first IF. It is designed for use with a ceramic filter, with an output impedance of Ω. A series resistor can be used to raise the impedance for use with a crystal filter, which typically has an input impedance of. kω. The second mixer input impedance is approximately. kω; it requires an external Ω parallel resistor for use with a standard ceramic filter. Limiting IF Amplifier and Detector The limiter has approximately db of gain, which starts rolling off at. MHz. Although not designed for wideband operation, the bandwidth of the audio frequency amplifier has been widened to khz, which gives less phase shift and enables the receiver to run at higher data rates. However, care should be taken not to exceed the bandwidth allowed by local regulations. The MC is designed for use with an LC quadrature detector, and does not have sufficient drive to be used with a ceramic discriminator. The MC was designed to use a ceramic discriminator, but can also be run with an LC quad coil, as mentioned in the Test Circuit Information section. The data shown in Figures and was taken using a murata CDBC ceramic discriminator which has been specially matched to the MC. Both the choice of discriminators and the external matching circuit will affect the distortion and recovered audio. RSSI/Op Amp The Received Signal Strength Indicator (RSSI) on the MC/ has about db of range. The resistor needed to translate the RSSI current to a voltage output has been included on the internal circuit, which gives it a tighter tolerance. A temperature compensated reference current also improves the RSSI accuracy over temperature. On the MC, the op amp on board is connected to the output to provide a voltage buffered RSSI. On the MC, the op amp is not connected internally and can be used for the RSSI or as a data slicer (see Figure c) , SUPPLY VOLTAGE (Vdc)

7 Figure. PLL Controlled Narrowband FM Receiver at / MHz MC OSC OSC Out In VDD Fin D PD D PD D LD D VSS Fin MC. k k.. p k..8 µh. MHz Xtal p p p p. p. k p 8 st LO nd LO Limiter Varicap AF Demod 8... k. µh. MHz k pf pf RF Input Recovered Audio RSSI Output 8 k Quad Coil Figure. MHz Single Channel Application Circuit st LO External Oscillator Circuit Preamp for MC at. MHz.8 µ. k k p. k X 8 p p L Q. µf p p fosc =. MHz Q MPS X.8 MHz rd Overtone Series Resonant Crystal L.8 µh Inductor (Coilcraft Part # J8) RF Input p p p L. k p k. µ L Q p. µf p To Mixer Q MPS L. µh L. µh

8 Figure a. Single Channel Narrowband FM Receiver at. MHz Buffered LO Output.. k. µh. p p MHz Xtal. p p. k p st LO nd LO MC Varicap... µh. MHz Figure. pf p RF Input Ω Source. MHz Xtal 8 Limiter Demod 8 AF. k k Recovered Audio RSSI Output k Quad Coil Figure b. PC Board Component View.k p p p p p. MHz XT CF KHz MHz XT. k MC... MHz CF p p.k k. NOTES:.. µh tunable (unshielded) inductor. MHz Series mode resonant rd Overtone Crystal.. µh tunable (shielded) inductor.. MHz Fundamental mode crystal, pf load. ceramic filter, murata CFU B or equivalent. Quadrature coil, Toko MC 88Z (mm) or Toko RMC AHM (mm).. MHz ceramic filter, murata SFE.MJ A or equivalent... K K k MC Figure c. Optional Data Slicer Circuit (Using Internal Op Amp) Vin (Pin ) k k. k k FSK Data Output. M 8

9 Figure 8. PC Board Solder Side View RF IN L.O. AUDIO V CC GROUND. SPEAKER RSSI MC MC. (Circuit Side View) Figure. PC Board Component View.k p p p p p. MHz XT CF KHz MHz XT. k MC... MHz CF p p.k k. NOTES:.. µh tunable (unshielded) inductor. MHz Series mode resonant rd Overtone Crystal.. µh tunable (shielded) inductor.. MHz Fundamental mode crystal, pf load. ceramic filter, murata CFU B or equivalent. discriminator, murata CDBC or equivalent.. MHz ceramic filter, murata SFE.MJ A or equivalent. p...k k K MC

10 Figure a. Single Channel Narrowband FM Receiver at. MHz MC Figure.. Buffered LO Output. k.. µh MHz Xtal p p p. p. k p st LO nd LO Varicap... µh. MHz pf pf RF Input Ω Source. MHz Xtal 8 Limiter Demod AF 8. k k Recovered Audio p. k murata Resonator CDBC RSSI Output Figure b. Optional Audio Amplifier Circuit Recovered Audio. k. MC 8 Speaker k

11 Figure. MC Internal Schematic 8 k 8. k. k. k. k k. k. k. k. p First LO First Mixer Second LO Second Mixer Op Amp Figure. k Bias. p k k. k Limiting IF Amplifier Detector and Audio Amplifier This device contains active transistors.

12 Figure. MC Internal Schematic 8 k 8. k. k. k. k k. k. k. k. p First LO First Mixer Second LO Second Mixer Figure. k Op Amp Bias. p k k. k Limiting IF Amplifier Detector and Audio Amplifier This device contains active transistors.

13 OUTLINE DIMENSIONS P SUFFIX PLASTIC PACKAGE CASE ISSUE D A B NOTES:. CHAMFERED CONTOUR OPTIONAL.. DIMENSION L TO CENTER OF LEADS WHEN FORMED PARALLEL.. DIMENSIONING AND TOLERANCING PER ANSI Y.M, 8.. CONTROLLING DIMENSION: INCH. T SEATING PLANE G E F N K C D PL. (.) M T A M L NOTE M J PL. (.) M T B M DIM A B C D E F G J K L M N INCHES MIN MAX BSC.. BSC... BSC.. MILLIMETERS MIN MAX BSC... BSC BSC.. T SEATING PLANE A D PL. (.) M T A S B S G PL B C K DW SUFFIX PLASTIC PACKAGE CASE E (SO L) ISSUE E P PL. (.) M B J F M M R X NOTES:. DIMENSIONING AND TOLERANCING PER ANSI Y.M, 8.. CONTROLLING DIMENSION: MILLIMETER.. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION.. MAXIMUM MOLD PROTRUSION (.) PER SIDE.. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE (.) TOTAL IN EXCESS OF D DIMENSION AT MAXIMUM MATERIAL CONDITION. DIM A B C D F G J K M P R MILLIMETERS MIN MAX BSC. BSC INCHES MIN MAX

14 Motorola reserves the right to make changes without further notice to any products herein. Motorola makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does Motorola assume any liability arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation consequential or incidental damages. Typical parameters which may be provided in Motorola data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including Typicals must be validated for each customer application by customer s technical experts. Motorola does not convey any license under its patent rights nor the rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall indemnify and hold Motorola and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and are registered trademarks of Motorola, Inc. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. Mfax is a trademark of Motorola, Inc. How to reach us: USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; JAPAN: Motorola Japan Ltd.; SPD, Strategic Planning Office,, P.O. Box, Denver, Colorado 8. or 8 Nishi Gotanda, Shinagawa ku, Tokyo, Japan Customer Focus Center: 8 Mfax : RMFAX@ .sps.mot.com TOUCHTONE ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, Motorola Fax Back System US & Canada ONLY 8 88 Ting Kok Road, Tai Po, N.T., Hong Kong HOME PAGE: MC/D

ML13135 FM Communications Receiver; Dual Conversion Narrowband FM Receiver

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