ML13175_08 LANSDALE | Alldatasheet

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Technical content

  • UHF Current Controlled Oscillator
  • Uses Easily Available 3rd Overtone or Fundamental Crystals for Reference
  • Fewer External Parts Required
  • Low Operating Supply V oltage (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
  • (ML13175) fo = 8 x fref, (ML13176) fo = 32 x fref
  • Operating Temperature Range - TA = -40° to +85°C ML13175-5P PLASTIC PACKAGE CASE 751B (SO–16) CROSS REFERENCE/ORDERING INFORMATION MOTOROLA SO 16 MC13175D ML13175-5P SO 16 MC13176D ML13176-5P LANSDALEPACKAGE Note: Lansdale lead free ( Pb) product, as it becomes available, will be identified by a part number prefix change from ML to MLE. PIN CONNECTIONS Xtale PDout ICont VEE NC Osc 4 NC Osc 1 Xtalb Reg. Gnd Enable VCC Out 1 Out 2 Out Gnd Imod

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 V EE 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. (ML13175); 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

ML13175/ML13176 LANSDALE Semiconductor, Inc.

  • 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

LANSDALE Semiconductor, Inc. ML13175/ML13176 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 ∆fosc versus ICont, Figure 5 shows the ∆fosc versus ICont at – 40° C, + 25° C and + 85° C for 320 MHz. The CCO may be FM modulated as shown in Figure 17, ML13176 320 MHz FM Transmitter. A detailed discussion is found in the Applications Information section.

7 PDout

4.0k VCC 4.0k PDout 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. www.lansdale.comPage 3 of 16 Issue c

ML13175/ML13176 LANSDALE Semiconductor, Inc. PIN FUNCTION DESCRIPTIONS 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.

9 Xtalb

4.0k 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 p 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 23 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. www.lansdale.comPage 4 of 16 Issue c

ML13175/ML13176 LANSDALE Semiconductor, Inc. Figure 17a. 320 MHz ML13176 FM Transmitter NOTES: 1. 50 Ω coaxial balun, 2 inches long. 2. 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. 3. RFC1 is 180 nH Coilcraft surface mount inductor or 190 nH Coilcraft 146–05J08. 4. Recommended source is a Coilcraft ™slot seven 7.0 mm tuneable inductor, part #7M3–682. 5. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance. 1Osc Tank Coilcraft 146–04J08 0.146µ 51p 51p f/32 Crystal Fundamental (5) 6.8 (4) 220p VCC 0.47µ 27k VCC VCC RFC1 (3) 510p 50Ω (1) RF Output to Antenna 0.047µ 1.1k RF Level Adjust VCC = 3.8 to

3.3 Vdc

9.1k 15k 18k 100k 0.47µ 1.0k 2N4402 (2) VEE Data Input (1.6 Vp–p) 0.1µ 5.0k CW VCC SMA Figure 17b. 320 MHz NBFM Transmitter NOTES: 1. 50 Ω coaxial balun, 2 inches long. 2. 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. 3. RFC1 is 180 nH Coilcraft surface mount inductor. 4. RFC2 and RFC3 are high impedance crystal frequency of 10 MHz; 8.2 µH molded inductor gives XL > 1000 Ω.. 5. A single varactor like the MV2105 may be used whereby RFC2 is not needed. 6. The crystal is a parallel resonant, fundamental mode calibrated with 32 pF load capacitance. RF Output to Antenna 1Osc Tank Coilcraft 146–04J08 0.146µ 100p 180p f/32 Crystal Fundamental 10MHz (6) VCC 0.47µ 27k VCC VCC (3.6 Vdc – Lithium Battery) RFC1 470p UT–034 (1) 0.047µ 1.0k RF Level Adjust VCC 130k 33k 6.2k 9.1k 15k 15k 4700p 1.0k 2N4402 (2) VEE 0.1µ 5.0k CW VCC External Loop Amp 10p RFC2 RFC3 (4) VCC 1.0k (5) MMBV432L 0.01µ 10µ Audio or Data Input SMA (3) Legacy Applications Information www.lansdale.comPage 10 of 16 Issue c

ML13175/ML13176 LANSDALE Semiconductor, Inc. Manufacturers specify crystal for either series or parallel res- onant operation. The frequency for the parallel mode is cali- brated 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 T wo types of crystal oscillator circuits are used in the appli- cations circuits: 1) fundamental mode common emitter Colpitts (Figures 1, 17a, 17b and 21) and 2) third overtone impedance inversion Colpitts (also Figures 1 and 21). The fundamental mode common emitter Colpitts uses a par- allel resonant crystal calibrated with a 32 pf load capacitance. The capacitance values are chosen to provide excellent fre- quency stability and output power of > 500 mVp–p at Pin 9. In Figures 1 and 21, the fundamental mode reference oscilla- tor is fixed tuned relying on the repeatability of the crystal and passive network to maintain the frequency, while in the circuit shown in Figure 17, 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 21), the reference oscillator operates with the third overtone crystal at 40.0000 MHz. Thus, the ML13175 is operated at 320 MHz (f o/8 = crystal; 320/8) = 40.0000 MHz. The resistor across the crystal ensures that the crystal will operate in the series resonance mode. A tuneable inductor is used to adjust the oscillation frequency; it forms a parallel resonant circuit with the series and parallel combina- tion of the external capacitors forming the divider and feed- back network and the base–emitter capacitance of the devices. If the crystal is shorted, the reference oscillator should free–run at the frequency dictated by the parallel reso- nant 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 ML13175 up to at least 480 MHz and the ML13176 up to

950 MHz (based on the maximum capability of the divider

netowork). ENABLER (Pin 11) The enabling resistor at Pin 11 is calculated by: Reg. enable = VCC – 1.0 Vdc/lreg. enable From Figure 4, lreg.enable is chosen to be 75µA. 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 intercon- nect 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 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 com- position of the lithium compound, construction and the bat- tery size. A 1300 mA/hr rating can be achieved in the cylin- drical 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 sim- ple 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 ML13175 and ML13176 are designed to accommodate Amplitude Shift Keying (ASK). ASK modulation is a form of digital modulation correspon- ding 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 abbre- viated OOK). The resultant amplitude modulated waveform consists of RF pulses called marks, representing binary 1 and spaces representing binary 0. Legacy Applications Information www.lansdale.comPage 12 of 16 Issue c

Figure 21. 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 23).

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

ML13175/ML13176 LANSDALE Semiconductor, Inc. Figure 23. Power Output versus Modulation CurrentPO, POWER OUTPUT (dBm)

ML13175/ML13176 LANSDALE Semiconductor, Inc. OUTLINE DIMENSIONS A B C D F G J K M P R 9.80 3.80 1.35 0.35 0.40 0.19 0.10 5.80 0.25 0.393 0.157 0.068 0.019 0.049 0.009 0.009 0.244 0.019 10.00 4.00 1.75 0.49 1.25 0.25 0.25 6.20 0.50 0.386 0.150 0.054 0.014 0.016 0.008 0.004 0.229 0.010 (ML13175-5P, ML13176-5P) PLASTIC PACKAGE CASE 751B (SO–16) MIN MIN MAX MAX MILLIMETERS INCHES DIM 1.27 BSC 0.050 BSC 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. 751B–01 IS OBSOLETE, NEW STANDARD 751B–03. 1 8 916 P

16 PLD

K CG M R X 45° F J 0.25 (0.010) M T S SAB MM0.25 (0.010) B 8 PL SEATING PLANE Lansdale Semiconductor reserves the right to make changes without further notice to any products herein to improve reliabil- ity, 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 cus- tomer’s technical experts. Lansdale Semiconductor is a registered trademark of Lansdale Semiconductor, Inc. www.lansdale.comPage 16 of 16 Issue c