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Low-Cost RF Synthesizer Uses Generic ICs - 24-Jun-10 EDN-Design Ideas You can design a hardware-based frequency synthesizer with one inexepensive IC and a few passive components. Such synthesizer chips are not always available, however, because they are typically single-sourced and are not in stock with parts distributors. The need for a working circuit in a short time and using common parts prompted the creation of the circuit in this Design Idea. The synthesizer covers the US commercial AM(amplitude-modulation) broadcast band. It tunes in 10-kHz steps from 500 to 1800 kHz, but you can scale the frequencies for other applications__ Circuit Design by James B Wood, Inovonics Inc, Felton, CA
Low-cost, programmable oscillator operates at 2 GHz - 05/11/00 EDN-Design Ideas All wireless communication systems need a local oscillator. Figure 1 shows a low-cost PLL circuit for the 2-GHz band for such applications as industrial, scientific, and medical (ISM]and satellite personal-communication systems (S-__ Circuit Design by A Navarro, M Rostami, and JN Matos, Instituto de TelecomunicaƧoes, Aveiro University, Portugal
LTC1436-PLL Low Noise Switching Regulator Helps Control EMI - DN141 Design Notes___ Linear Technology/Analog Devices
MC145151 PLL FM Transmitter - This PLL has been designed with an old Motorola circuit :the MC145151. The VCO is based on a "Colpitz" oscillator equiped with a FET Transistor. (J310) Two varicap Diodes are used in order to reduce the global noise of the VCO. In addition, these two diodes allow the PLL to keep the lock status through a large range of climatic conditions. An another J310 is used in order to match the impedance between the oscillator and the fist amplifier stage. A MSA1105 from Minicircuits increases the RF power level coming from the VCO to +14dBm. A simple low pass filter rejects the second harmonic to -20 dB. (Worst case) Finally, a 7 dB attenuator and a second amplifier stage (BFR96S) achieve this radio design. __ Designed by Michel P
MC145170 PLL FM transmitter - This new FM transmitter is very simple and doesn't need any RF tuning. First of all , we have used an integrated VCO: The POS150 from Mini-circuits. This excellent RF circuit covers all the FM Band in a voltage range of 4V to 8V. The Kvco factor is very stable all over the FM band, (08/08/08) __ Designed by Michel P
Micro Spy PLL FM Transmitter - This micro spy PLL FM Transmitter transmits on the 160MHz frequency (if we use a 40MHz quartz) and therefore can be listened through a receiver tuned on this frequency. This circuit can be used to on various frequencies, for example on the FM band 88-108 just modifying some components, among which the quartz (25MHz). Voice is detected by an electret microphone, then it is amplified and filtered by U1 pass-band in order then to be modulated from the carrier section, where through the varicap diode it "mixes" with the frequency generated by the quartz, that guarantees an adapted stability. Practically the modulating voltage is obtained applying the audio signal to the resonating circuit varicap diode that determines the carrier oscillation. The carrier frequency (160 MHz) must be greater than the modulating frequency (300-3300 Hz) audio band. The transmission is on the fourth harmonic, therefore 160MHz, the oscillation frequency of the driver RF transistor Q1. A small calibration is allowed acting on the L1 inductance and the C1 Trimmer Capacitor. __
Optimizing VCO/PLL Evaluations & PLL Synthesizer Designs - AN-95-006 Application Note___ MiniCircuits.com
Phase Locked Loop Frequency Synthesizer Demonstration Board - This document details the evaluation procedures and usage of the Hewlett-Packard HPLL-8001 demonstration circuit board and evaluation software. All operating conditions and electrical characteristics of the HPLL-8001 are described in the current version of the data sheet___ HP Application Note 1145
Phase locked loop fundamentals - Application Note___ MiniCircuits.com
Phase Locking & Tuning - Schematic + software links __ Jan Kolar
Phase-Locking ULNs for Optimum Performance - Phase-locking two ultra-low noise oscillators is an effective way to achieve excellent noise performance both close-in and at the noise floor. To illustrate the technique, this note describes a PLL using a 5 MHz ULN as the reference and a 100 MHz ULN as the locked oscillator. The 5 MHz reference exhibits superior phase noise, even after multiplication, for offset frequencies below about 300 Hz and the 100 MHz oscillator has better noise for offsets above 300 Hz. By setting the loop bandwidth near 300 Hz the locked 100 MHz phase noise is optimized. __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Phase-sequence indicator uses few passive components - 07/06/06 EDN-Design Ideas Debug three-phase power-line wiring with this easily constructed circuit__ Circuit Design by Metodi Iliev, University of CaliforniaBerkeley
PLL Exciter - This is a PLL controller that works with the VCO/Modulator that I designed. Use these two modules together for a complete baseband-capable exciter unit. This PLL controller features a rock-stable crystal controlled reference, in conjunction with a programmable dividing network which allows the transmitter to be tuned in 100Khz steps from 79.9Mhz to 109.7Mhz by means of digital thumbwheel switches.___ Electronics DIY
PLL Filter Blocks Undesired Frequencies - 12/15/10 EDN-Design Ideas Block frequencies such as interference from ac mains. [Design Ideas by Stephen Kamichik, Ile Bizard, PQ, Canada__ Circuit Design by Stephen Kamichik, Ile Bizard, PQ, Canada
PLL FM Transmitter - This is PLL FM Transmitter using SAA1057 chip. Transmitter can be operated from a PC through LPT port, or using a PC software as a driver. __
PLL FM Transmitter - This new FM transmitter is very simple and doesn't need any RF tuning. First of all , we have used an integrated VCO: The POS150 from Mini-circuits. This excellent RF circuit covers all the FM Band in a voltage range of 4V to 8V. The Kvco factor is very stable all over the FM band, (08/08/08) __ Designed by Michel P
PLL FM Transmitter using LMX1601, ATtiny2313 AT90S2313 - Here's a PLL FM Transmitter using LMX1601, ATtiny2313 or AT90S2313 microcontrollers. The common characteristic of all of the previous low power FM transmitters I've built over the decades, is that their operating frequency is determined by an LC resonant circuit. Some of them had excellent stability, some of them didn't, but I had always wanted to make one that is crystal controlled. Various schemes had been considered from time-to-time, including the direct approach of modulating the load capacitance of a a crystal oscillator, a whimsical phase modulation scheme involving a phase shifter, some balanced modulators, and limiting amplifiers, and at times, the down-to-earth and sober approach of modulating a VCO within a phase locked loop (PLL). While browsing Digikey's online catalog, I found the LMX1601 frequency synthesizer chip and thought: "Just maybe, the PLL approach is finally within my grasp." The LMX1601, which apparently was designed for use in cell phones, includes everything need to make two phase locked loops except for the VCOs. More importantly, one of the PLLs, specifically the "AUX" PLL, is specified to work in the FM broadcast band. The LMX1600 and the LMX1602 were also considered, but the LMX1601 was selected because it has a "500 MHz option", meaning that it can work down to about 50 MHz. __
PLL forms Simple Circuit MSK Demodulator - 12/17/98 EDN-Design Ideas In minimum-shift-keying(MSK) signaling, two frequencies that differ by the bit rate represent a one bit and a zero bit. Normally, the frequency shift occurs at the peak of a cycle, so that neither the amplitude nor the slope of the waveform shows a discontinuity. We needed to transmit 300-baud ASCII text using ultrasonic transducers. These devices have a very narrow bandwidth around their 25-kHz resonant frequency, making MSK the obvious choice for modulation. A zero Page includes
several designs. Scroll to find this one__ Circuit Design by JTom Napier, North Wales, PA
PLL IC Forms Simple Circuit Digital Phase Shifter - 01/04/96 EDN-Design Ideas A phase shifter is a vital block in some signal-processing and clock-distribution applications. Another important application is in benchmarking digital phase detectors. The circuit in Figure 1, an especially appropriate one for evaluating phase detectors, uses only two industry-standard ICs(CD4046 and LM311]. It relies on digital PLL techniques__ Circuit Design by Haldun Karaca, DE University Bornova, Izmir, Turkey
PLL implements FPGA-based SDRAM controller - EDN-Design Ideas March 26, 1998 [ NOTE
: File has multiple design, scroll for this one.] As FPGA capabilities increase and time to market decreases, FPGAs gain more acceptance for implementing both data and control paths. Thus, they find wide use as controllers and datapath glue logic for fast-page DRAMs.__ Circuit Design by Eddy Debaere, Barco Graphics, Ghent, Belgium
PLL Module - This schematic originally comes from a Dutch magazine called Free Radio Magazine in the mid eighties. It's just a PLL nothing more, nothing less. The resistor named R can be replaced by a 50 Ohm type if the power supply is 5 Volts. The dividing ratio can be programed with IC2. For the ratios see table 1. Example: If the input signal has a frequency of 10MHz, the crystal frequency output is 10.240-10.000=0.24. Now looking at table 1, we see we can make 24 by combining the 8 and 16 program switches (pin 11 and pin 12 closed to Vcc). __
PLL Oscillator - This PLL was first published in March 1983 in Free Radio Magazine and was re-published a year later in the same magazine. It uses the well known 4046 as PLL and a CD4059 as programmable divider. __
PLL Solid State Tesla Coil 1 - My first SSTC which works well enough to show to anyone. __
PLL SSTC 1.5 - The PLL SSTC 1 has been given an extreme makeover. __
PLL Stereo FM Transmitter - The circuit shown here is of a good Stereo FM transmitter that can transmit high quality signals up to a range of 70 feet. The circuit is based on BH1417 PLL stereo transmitter IC from Rhom semiconductors. The IC has separate audio processing sections for the left and right channels, pre emphasis circuit for improving signal to noise ratio, crystal control circuitry for accurate frequency locking, multiplex circuit for making sum (left plus right) and difference (left minus right) {see this article for better understanding Stereo decoder circuit} etc. Another important feature of this IC is that the transmission frequency can be set using a 4 channel DIP switch. The IC can be powered from anything between 4 to 6V DC and has an output power around 20mW. At full output power the circuit consumes only 20mA and has a channel separation of 40dB.There are 14 possible preset transmission frequencies, starting from 88.7MHz and incrementing in steps of 0.2MHz that can be selected using the DIP switch. The PLL circuitry of the IC is so precise that there is practically no frequency drift. __
PLL synchronizes power-supply IC - 07/16/98 EDN-Design Ideas It is often desirable to synchronize a switching power supply to a system clock or to a second supply. If the power-supply controller has no synchronization pin, you can add a low-value resistor in series with the oscillator capacitor, thereby developing a synchronizationFile has several circuits, please scroll to find this one__ Circuit Design by Kurk Mathews, Linear Technology Corp, Milpitas, CA
PLL synthesizing oscillator 1 The PLL synthesizer oscillation circuit to introduce here is using the PLL frequency synthesizer (MB87014A). It is possible to make oscillate the stable high frequency signal. The PLL is the abbreviation of Phase Locked Loop. In the operation of the PLL, it compares the frequency of the reference frequency oscillator and the frequency of the voltage controlled oscillator by the phase. When there is a difference of the phase, it works as if to control the VCO and to lose the difference. It controls repeatedly (loop) like the oscillation frequencyphase comparisonvoltage controloscillation frequency. __ Designed by Seiichi Inoue
PLL Synthesizing Oscillator 2 - In this page, I introduce the PLL synthesizer oscillator which used MC145163. As for the operation principle of the PLL synthesizer oscillator, see "Principle of the PLL oscillator". This IC for the PLL can specify a dividing ratio directly with the BCD. The output of the BCD counter can be directly connected. There is not a serial data generator, being necessary. __ Designed by Seiichi Inoue
PLL Synthesizing Oscillator 3 - I introduce the PLL synthesizer oscillator by MC14046B which can change the frequency. The PLL oscillator can be made using three kinds pieces of the ICs like the figure above. Because most of the functions are stored in the ICs, there are few, too, circumference circuits and the making is easy. The BCD (Binary Coded Decimal) switch is used to change the frequency. __ Designed by Seiichi Inoue
PLL Tuning Module - SAA1057 Dual-speed PLL designed for wideband FM transmitter. __
PLL using a TA7310P - The resistor named R can be replaced by a 50 Ohm type if the power supply is 5 Volts. The dividing ratio can be programed with IC2. For the ratios see table 1. Example: If the input signal has a frequency of 10MHz, the crystal frequency output is 10.240-10.000=0.24. Now looking at table 1, we see we can make 24 __
PLL-based converter controls light source - EDN-Design Ideas July 2, 1998 [ NOTE
: File has multiple design, scroll for this one.] Using the circuit in Figure 1, you can digitally control the light intensity of a lamp. The control loop is based on a PLL, in which the VCO comprises a light-to-frequency converter (TSL220) coupled to a light source that derives its drive from a switching regulator (L4970A). The output of the phase/frequency comparator (4046) serves as the control voltage for the switching regulator. The control voltage is proportional to the frequency error between the reference frequency (fREF) and the signal frequency (fIN) coming from the light-to-frequency converter.__ Circuit Design by Masso Gottardi, ITC-IRST, Trento, Italy
Programmable oscillator operates at 2 GHz - 05/11/00 EDN-Design Ideas All wireless communication systems need a local oscillator. Figure 1 shows a low-cost PLL circuit for the 2-GHz band for such applications as industrial, scientific, and medical (ISM]and satellite personal-communication systems (S-__ Circuit Design by A Navarro, M Rostami, and JN Matos, Instituto de TelecomunicaƧoes, Aveiro University, Portugal
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