MC13175 MOTOROLA | Alldatasheet

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/C0077/C0067/C0049/C0051/C0049/C0055/C0053 /C0077/C0067/C0049/C0051/C0049/C0055/C0054 SEMICONDUCTOR TECHNICAL DATA UHF FM/AM TRANSMITTER

ORDERING INFORMATION

TA = – 40° to +85°C SO–16 SO–16 PIN CONNECTIONS Order this document by MC13175/D D SUFFIX PLASTIC PACKAGE CASE 751B (SO–16) Xtale PD out ICont VEE NC Osc 4 NC Osc 1 Xtalb Reg. Gnd Enable VCC Out 1 Out 2 Out Gnd Imod 1MOTOROLA RF/IF DEVICE DATA /C0085/C0072/C0070 /C0070/C0077/C0047/C0065/C0077 /C0084/C0114/C0097/C0110/C0115/C0109/C0105/C0116/C0116/C0101/C0114 The MC13175 and MC13176 are one chip FM/AM transmitter subsystems designed for AM/FM communication systems. They include a Colpitts crystal reference oscillator, UHF oscillator, ÷ 8 (MC13175) or ÷ 32 (MC13176) prescaler and phase detector forming a versatile PLL system. Targeted applications are in the 260 to 470 MHz band and 902 to 928 MHz band covered by FCC Title 47; Part 15. Other applications include local oscillator sources in UHF and 900 MHz receivers, UHF and 900 MHz video transmitters, RF Local Area Networks (LANs), and high frequency clock drivers. The MC13175/76 offer the following features:

  • UHF Current Controlled Oscillator
  • Uses Easily Available 3rd Overtone or Fundamental Crystals for Reference
  • Fewer External Parts Required
  • Low Operating Supply Voltage (1.8 to 5.0 Vdc)
  • Low Supply Drain Currents
  • Power Output Adjustable (Up to +10 dBm)
  • Differential Output for Loop Antenna or Balun Transformer Networks
  • Power Down Feature
  • ASK Modulated by Switching Output On and Off
  • (MC13175) fo = 8 x fref; (MC13176) fo = 32 x fref

Figure 1. Typical Application as 320 MHz AM Transmitter

  1. 50 Ω coaxial balun, 1/10 wavelength at 320 MHz equals 1.5 inches.
  2. Pins 5, 10 & 15 are ground and connected to VEE which is the component/DC ground plane
  3. side of PCB. These pins must be decoupled to VCC ; decoupling capacitors should be placed
  4. as close as possible to the pins.
  5. The crystal oscillator circuit may be adjusted for frequency with the variable inductor
  6. (MC13175); recommended source is Coilcraft “slot seven” 7mm tuneable inductor, Part
  7. #7M3–821. 1.0k resistor. Shunting the crystal prevents it from oscillating in the fundamental

40.0000 MHz

10 MHz

2 MOTOROLA RF/IF DEVICE DATA

  • For testing purposes, VCC is ground (see Figure 2).

Figure 2. 320 MHz Test Circuit NOTES: 1. VCC is ground; while VEE is negative with respect to ground.

  1. Pins 5, 10 and 15 are brought to the circuit side of the PCB via plated through holes.

They are connected together with a trace on the PCB and each Pin is decoupled to VCC (ground).

  1. Recommended source is Coilcraft “slot seven” inductor, part number 7M3–821.

40 MHz

3MOTOROLA RF/IF DEVICE DATA PIN FUNCTION DESCRIPTIONS Pin Symbol Internal Equivalent Circuit Description/External Circuit Requirements 1 & 4 Osc 1, Osc 4 0sc 1 10k Osc 4 10k VCC CCO Inputs The oscillator is a current controlled type. An external oscillator coil is connected to Pins 1 and 4 which forms a parallel resonance LC tank circuit with the internal capacitance of the IC and with parasitic capacitance of the PC board. Three base–emitter capacitances in series configuration form the capacitance for the parallel tank. These are the base–emitters at Pins 1 and 4 and the base–emitter of the differential amplifier. The equivalent series capacitance in the differential amplifier is varied by the modulating current from the frequency control circuit (see Pin 6, internal circuit). A more thorough discussion is found in the Applications Information section.

5 VEE

5 Subcon

Supply Ground (VEE ) In the PCB layout, the ground pins (also applies to Pins 10 and 15) should be connected directly to chassis ground. Decoupling capacitors to VCC should be placed directly at the ground returns.

6 ICont

For VCC = 3.0 Vdc, the voltage at Pin 6 is approximately 1.55 Vdc. The oscillator is current controlled by the error current from the phase detector. This current is amplified to drive the current source in the oscillator section which controls the frequency of the oscillator. Figures 9 and 10 show the Δfosc versus ICont, Figure 5 shows the Δfosc versus ICont at – 40°C, + 25°C and +8 5°C for 320 MHz. The CCO may be FM modulated as shown in Figures 18 and 19, MC13176 320 MHz FM Transmitter. A detailed discussion is found in the Applications Information section.

7 PD out

4.0k VCC 4.0k PD out Phase Detector Output The phase detector provides ± 30 µA to keep the CCO locked at the desired carrier frequency. The output impedance of the phase detector is approximately 53 kΩ . Under closed loop conditions there is a DC voltage which is dependent upon the free running oscillator and the reference oscillator frequencies. The circuitry between Pins 7 and 6 should be selected for adequate loop filtering necessary to stabilize and filter the loop response. Low pass filtering between Pin 7 and 6 is needed so that the corner frequency is well below the sum of the divider and the reference oscillator frequencies, but high enough to allow for fast response to keep the loop locked. Refer to the Applications Information section regarding loop filtering and FM modulation.

4 MOTOROLA RF/IF DEVICE DATA

Pin Symbol Internal Equivalent Circuit Description/External Circuit Requirements

8 Xtale VCC

Xtalb 12k 8.0k Crystal Oscillator Inputs The internal reference oscillator is configured as a common emitter Colpitts. It may be operated with either a fundamental or overtone crystal depending on the carrier frequency and the internal prescaler. Crystal oscillator circuits and specifications of crystals are discussed in detail in the applications section. Wi h V Vd h l Pi i i l9 Xtalb Xtale8 4.0k yp p With VCC = 3.0 Vdc, the voltage at Pin 8 is approximately 1.8 Vdc and at Pin 9 is approximately 2.3 Vdc. 500 to 1000 mVp–p should be present at Pin 9. The Colpitts is biased at 200 µA; additional drive may be acquired by increasing the bias to approximately 500 µA. Use 6.2 k from Pin 8 to ground. 10 Reg. Gnd VCC 5.0p Reg Regulator Ground An additional ground pin is provided to enhance the stability of the system. Decoupling to the VCC (RF ground) is essential; it should be done at the ground return for Pin 10.

11 Enable

Reg. Gnd Subcon Enable 5.0p 8.0k 2.4k Device Enable The potential at Pin 11 is approximately 1.25 Vdc. When Pin 11 is open, the transmitter is disabled in a power down mode and draws less than 1.0 µA ICC if the MOD at Pin 16 is also open (i.e., it has no current driving it). To enable the transmitter a current source of 10 µA to 90 µA is provided. Figures 3 and 4 show the relationship between ICC , VCC and Ireg. enable. Note that ICC is flat at approximately 10 mA for Ireg. enable = 5.0 to 100 µA (Imod = 0).

12 VCC

Supply Voltage (VCC ) The operating supply voltage range is from 1.8 Vdc to 5.0 Vdc. In the PCB layout, the VCC trace must be kept as wide as possible to minimize inductive reactances along the trace; it is best to have it completely fill around the surface mount components and traces on the circuit side of the PCB. 13 & 14 Out 1 and Out 2 VCC 161413 Differential Output The output is configured differentially to easily drive a loop antenna. By using a transformer or balun, as shown in the application schematic, the device may then drive an unbalanced low impedance load. Figure 6 shows how much the Output Power and Free–Running Oscillator Frequency change with temperature at 3.0 Vdc; Imod = 2.0 mA.

15 Out_Gnd ImodOut 2Out 1

161413 Output Ground

This additional ground pin provides direct access for the output ground to the circuit board VEE .

16 Imod

Out_Gnd AM Modulation/Power Output Level The DC voltage at this pin is 0.8 Vdc with the current source active. An external resistor is chosen to provide a source current of 1.0 to 3.0 mA, depending on the desired output power level at a given VCC . Figure 28 shows the relationship of Power Output to Modulation Current, Imod . At VCC = 3.0 Vdc, 3.5 dBm power output can be acquired with about 35 mA ICC . For FM modulation, Pin 16 is used to set the desired output power level as described above. For AM modulation, the modulation signal must ride on a positive DC bias offset which sets a static (modulation off) modulation current. External circuitry for various schemes is further discussed in the Applications Information section.

5MOTOROLA RF/IF DEVICE DATA DOCUMENT CONTAINS SCANNED IMAGES WHICH COULD NOT BE PROCESSED FOR PDF FILES. FOR COMPLETE DOCUMENT WITH IMAGES PLEASE ORDER FROM MFAX OR THE LITERATURE DISTRIBUTION CENTER

6 MOTOROLA RF/IF DEVICE DATA

Figure 3. Supply Current Figure 4. Supply Current versus Figure 5. Change Oscillator Frequency Figure 6. Change in Oscillator Frequency and Figure 7. MC13175 Reference Oscillator Figure 8. MC13176 Reference Oscillator

8 MOTOROLA RF/IF DEVICE DATA

Figure 11. Block Diagram of MC1317XD PLL are controlled externally by loop filtering. Figure 12. Type 2 Second Order Response transfer functions F(s) = 1 + t2s/1 + (t1 + t2)s. Figure 13. Lag–Lead Low Pass Filter

Figure 14. Modified Low Pass Loop Filter

620 R 2

gradually shifted away from the free running frequency, ff. the hold–in range is equal to the DC loop gain, Kv /C0002 N. temperature coefficients of the ferrite tuned CCO inductor. must be carefully considered. Kp = is fixed internally and cannot be altered. Ko = of greater control range with more current swing. Ka = since the phase detector only supplies ± 30 µA. reduce the level of the crystal sidebands. Figure 15. External Loop Amplifier

10 MOTOROLA RF/IF DEVICE DATA

Figure 16 shows the improved hold–in range of the loop. Figure 16. MC13176 Reference Oscillator factor, ∂ = 0.707, the loop bandwidth = 1.64 kHz. push–pull current output of the phase detector. carrier power output at 3.5 dBm for VCC = 3.0 Vdc. Figure 17. Figure 19 shows an application example for NBFM Figure 17. Microphone Amplifier the crystal sideband spurs to a minimal level.

Figure 18. 320 MHz MC13176D FM Transmitter NOTES: 1. 50 Ω coaxial balun, 2 inches long.

  1. Pins 5, 10 and 15 are grounds and connnected to VEE which is the component’s side ground plane.

These pins must be decoupled to VCC ; decoupling capacitors should be placed as close as possible to the pins.

  1. RFC1 is 180 nH Coilcraft surface mount inductor or 190 nH Coilcraft 146–05J08.
  2. Recommended source is a Coilcraft “slot seven” 7.0 mm tuneable inductor, part #7M3–682.
  3. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance.

3.3 Vdc

Figure 19. 320 MHz NBFM Transmitter NOTES: 1. 50 Ω coaxial balun, 2 inches long.

  1. Pins 5, 10 and 15 are grounds and connnected to VEE which is the component’s side ground plane. These

pins must be decoupled to VCC ; decoupling capacitors should be placed as close as possible to the pins.

  1. RFC1 is 180 nH Coilcraft surface mount inductor.
  2. RFC2 and RFC3 are high impedance crystal frequency of 10 MHz; 8.2 µH molded inductor gives XL > 1000 Ω ..
  3. A single varactor like the MV2105 may be used whereby RFC2 is not needed.
  4. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance.

12 MOTOROLA RF/IF DEVICE DATA

Figure 20. Input Data Waveform Figure 21. Frequency Deviation Figure 22. Modulation Spectrum Figure 23. Unmodulated Carrier the metal plates and leads that make contact with it. are so far off frequency that their effects are negligible. Figure 24. Crystal Equivalent Circuit in the feedback loop keeping the oscillator on frequency.

13MOTOROLA RF/IF DEVICE DATA Manufacturers specify crystal for either series or parallel resonant operation. The frequency for the parallel mode is calibrated with a specified shunt capacitance called a “load capacitance.” The most common value is 30 to 32 pF. If the load capacitance is placed in series with the crystal, the equivalent circuit will be series resonance at the specified parallel–resonant frequency. Frequencies up to 20 MHz use parallel resonant crystal operating in the fundamental mode, while above 20 MHz to about 60 MHz, a series resonant crystal specified and calibrated for operation in the overtone mode is used. Application Examples Two types of crystal oscillator circuits are used in the applications circuits: 1) fundamental mode common emitter Colpitts (Figures 1, 18, 19, and 25), and 2) third overtone impedance inversion Colpitts (also Figures 1 and 25). The fundamental mode common emitter Colpitts uses a parallel resonant crystal calibrated with a 32 pf load capacitance. The capacitance values are chosen to provide excellent frequency stability and output power of > 500 mVp–p at Pin 9. In Figures 1 and 25, the fundamental mode reference oscillator is fixed tuned relying on the repeatability of the crystal and passive network to maintain the frequency, while in the circuit shown in Figures 18 and 19, the oscillator frequency can be adjusted with the variable inductor for the precise operating frequency. The third overtone impedance inversion Colpitts uses a series resonance crystal with a 25 ppm tolerance. In the application examples (Figures 1 and 25), the reference oscillator operates with the third overtone crystal at 40.0000 MHz. Thus, the MC13175 is operated at 320 MHz (fo/8 = crystal; 320/8 = 40.0000 MHz. The resistor across the crystal ensures that the crystal will operate in the series resonant mode. A tuneable inductor is used to adjust the oscillation frequency; it forms a parallel resonant circuit with the series and parallel combination of the external capacitors forming the divider and feedback network and the base–emitter capacitance of the device. If the crystal is shorted, the reference oscillator should free–run at the frequency dictated by the parallel resonant LC network. The reference oscillator can be operated as high as 60 MHz with a third overtone crystal. Therefore, it is possible to use the MC13175 up to at least 480 MHz and the MC13176 up to 950 MHz (based on the maximum capability of the divider network). Enable (Pin 11) The enabling resistor at Pin 11 is calculated by: R eg. enable = VCC – 1.0 Vdc/Ireg. enable From Figure 4, Ireg. enable is chosen to be 75 µA. So, for a VCC = 3.0 Vdc Rreg. enable = 26.6 kΩ , a standard value 27 kΩ resistor is adequate. Layout Considerations Supply (Pin 12): In the PCB layout, the VCC trace must be kept as wide as possible to minimize inductive reactance along the trace; it is best that VCC (RF ground) completely fills around the surface mounted components and interconnect traces on the circuit side of the board. This technique is demonstrated in the evaluation PC board. Battery/Selection/Lithium Types The device may be operated from a 3.0 V lithium battery. Selection of a suitable battery is important. Because one of the major problems for long life battery powered equipment is oxidation of the battery terminals, a battery mounted in a clip–in socket is not advised. The battery leads or contact post should be isolated from the air to eliminate oxide build–up. The battery should have PC board mounting tabs which can be soldered to the PCB. Consideration should be given for the peak current capability of the battery. Lithium batteries have current handling capabilities based on the composition of the lithium compound, construction and the battery size. A 1300 mA/hr rating can be achieved in the cylindrical cell battery. The Rayovac CR2/3A lithium–manganese dioxide battery is a crimp sealed, spiral wound 3.0 Vdc, 1300 mA/hr cylindrical cell with PC board mounting tabs. It is an excellent choice based on capacity and size (1.358″ long by 0.665″ in diameter). Differential Output (Pins 13, 14) The availability of micro–coaxial cable and small baluns in surface mount and radial–leaded components allows for simple interface to the output ports. A loop antenna may be directly connected with bias via RFC or 50 Ω resistors. Antenna configuration will vary depending on the space available and the frequency of operation. AM Modulation (Pin 16) Amplitude Shift Key: The MC13175 and MC13176 are designed to accommodate Amplitude Shift Keying (ASK). ASK modulation is a form of digital modulation corresponding to AM. The amplitude of the carrier is switched between two or more values in response to the PCM code. For the binary case, the usual choice is On–Off Keying (often abbreviated OOK). The resultant amplitude modulated waveform consists of RF pulses called marks, representing binary 1 and spaces representing binary 0.

14 MOTOROLA RF/IF DEVICE DATA

Figure 25. ASK 320 MHz Application Circuit

  1. Pins 5, 10 and 15 are ground and connnected to VEE which is

as close as possible to the pins.

  1. The crystal oscillator circuit may be adjusted for frequency with

crystal prevents it from oscillating in the fundamental mode.

  1. The On–Off keyed signal turns the output of the transmitter off and on with

by the resistor which sets Imod = VTTL – 0.8 / Rmod . (see Figure 28).

  1. S1 simulates an enable gate pulse from a microprocessor which will

time is applied to the Enable (Pin 11).

16 MOTOROLA RF/IF DEVICE DATA

amplitude of the input signals is approximately 800 mVp–p. standard value resistor of 3.9 k. Figure 29. Analog AM Transmitter Figure 30. Power Output of Unmodulated Carrier Figure 31. Input Signal and AM Modulated Figure 32. Input Signal and AM Modulated

17MOTOROLA RF/IF DEVICE DATA OUTLINE DIMENSIONS D SUFFIX PLASTIC PACKAGE CASE 751B–05 (SO–16) ISSUE J NOTES: 1. DIMENSIONING AND TOLERANCING PER ANSI Y14.5M, 1982. 2. CONTROLLING DIMENSION: MILLIMETER. 3. DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. 4. MAXIMUM MOLD PROTRUSION 0.15 (0.006) PER SIDE. 5. DIMENSION D DOES NOT INCLUDE DAMBAR PROTRUSION. ALLOWABLE DAMBAR PROTRUSION SHALL BE 0.127 (0.005) TOTAL IN EXCESS OF THE D DIMENSION AT MAXIMUM MATERIAL CONDITION. 16 9 SEATING PLANE F JM R X 45/C0095 G

8 PLP–B–

–A– M0.25 (0.010) B S –T– D K C 16 PL SBM0.25 (0.010) A ST DIM MIN MAX MIN MAX INCHESMILLIMETERS A 9.80 10.00 0.386 0.393 B 3.80 4.00 0.150 0.157 C 1.35 1.75 0.054 0.068 D 0.35 0.49 0.014 0.019 F 0.40 1.25 0.016 0.049 G 1.27 BSC 0.050 BSC J 0.19 0.25 0.008 0.009 K 0.10 0.25 0.004 0.009 M 0 7 0 7 P 5.80 6.20 0.229 0.244 R 0.25 0.50 0.010 0.019 /C0095/C0095/C0095/C0095 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 : Nippon Motorola Ltd.: SPD, Strategic Planning Office, 141, P.O. Box 5405, Denver, Colorado 80217. 1–303–675–2140 or 1–800–441–2447 4–32–1 Nishi–Gotanda, Shagawa–ku, Tokyo, Japan. 03–5487–8488 Customer Focus Center: 1–800–521–6274 Motorola Fax Back System – US & Canada ONLY 1–800–774–1848 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 – http://sps.motorola.com/mfax/ HOME PAGE : http://motorola.com/sps/ MC13175/D