The vset pin will accept either a dc voltage or a pwm waveform. There are many unique market applications, such as the wireless communications market, where new. Basically, its a semiconductor diode in which a high resistivity intrinsic iregion. The singlepole singlethrow spst and singlepole doublethrow spdt based switch structures are outlined. It is a 3layer device in which an intrinsic layer i. Finally, the maximum rf power that the pin diode is capable of switching depends on the incident power, p a, z. A pin diode switch suitable for switching radiofrequency voltages has a series circuit of two oppositely polarized pin diodes, with a control current supplied to the junction between the two pin diodes through the collectoremitter path of a transistor and through an inductor.
This also reduces the capacitance between both the regions, thus raising the level of isolation when the pin diode is reverse biased. At frequencies well below fc, the pin diode behaves as an ordinary pn junction diode. The large width of intrinsic layer imparts the ability to the diode to tolerate high reverse voltage without leading to the breakdown of the diode. When the pin diode is forward biased, holes and electrons are injected into the iregion. Spdt shunt pin diode switch design of various microwave circuits using semiconductor devices can be carried out utilizing wipld microwave. A unique feature of the pin diode is its ability to control large amounts of rf power with much lower levels of dc.
Pasternack single pole eight throw sp8t pin diode switches cover frequency bands from 500 mhz to 40 ghz. Product brief rf pin diodes maximized rf performance at reduced form factor operating up to 6 ghz with highvoltage handling capabilities, infineon pin diodes come with low loss and low distortion level ensuring high quality and performance in a wide range of mobile communications and rf applications. Pin diode switching requirements figure 1shows a simplified schematic of a pin diode switch. High power 40 to 150 watt spst and spdt pin diode switches. In the case when no large input signal is present, the. Electronic circuits diode as a switch tutorialspoint. Pdf sic power schottky and pin diodes researchgate. Macoms pin switch and attenuator diodes provide broadband performance from 1 mhz to 70 ghz.
Please view our large selection of pin diodes below. Design and simulation of a sp4t switch based on the pin. The fastest pin diode driver is able to switch two pin diodes with a carrier lifetime. This one might think is only 20 mw and not any problem. Macom and its affiliates reserve the right to make changes to the products or information contained herein without notice. I was trying to do a pin diode tr switch in ltspice using a downloaded 1n4007 model but the diode didnt work like a pin. Driver circuits for high power pin diode switches the information in this chapter is presented as a guide for the rf switch switch driver interface. At these types of frequencies, a pin diode is fundamentally a device with an impedance controlled by its dc excitation. This report deals with a cryogenicallycooled, cband, pin diode switch developed for radio astronomy applications. The acronym pin corresponds to the semiconductor stack of ptype, intrinsic, and ntype material. Pdf this paper describes the semiconductor technology, packaging and characterization of a new pin diode for switching wcdma signal up to 10w.
Mcli pin diode switches are offered in many multiport models up to sp8t single pole eight throw that feature high isolation, low insertion loss, and fast switching times up to 100 nanoseconds. For new designs, a silicon switch can be combined with a more highly linearized. The pin limiter diode can be described as an incidentpowercontrolled, variable resistor. Resonant method is demonstrated in 3 by tuning with a parallel. Design and simulation of a sp4t switch based on the pin diode. This application note is intended to provide practical guidance in the selection of pin diodes for switch control circuit functions. In most cases, an absorptive switch can be used instead of a reflective, but not viceversa. A pin diode switch uses the pin diode as the nonlinear element low impedance, current in one.
What is the difference between pin diode switches and gaas switches. The im3 of a silicon pin switch is 70 dbc at the 1 watt level. The pam2861 includes the output switch and a highside output current sensing circuit, which uses an external resistor to set the nominal average output current. The pin diode drivers control the biasing of the pin diodes and thus a ects the speed of the switch. Pin diode switches are often used to control the path of rf signals. Pin diodes are used in this project as solid state switches in order to provide an alternate path for the current and isolate the sensitive sensor throughout the high. The gas fet preamp is connected directly to the pin diode switch with no additional protection. The diode in which the intrinsic layer of high resistivity is sandwiched between the p and nregion of semiconductor material such type of diode is known as the pin diode. Pin diode switch circuit for short time high current. High power multithrow pin diode switch modules v5 ma8334 series 1 macom technology solutions inc. After the pnjunction diode was developed in the year 1940s, the diode was first exercised as a highpower rectifier, lowfrequency during the year 1952.
Thus, the diode can be simply visualized as follows. This application note describes the use of pin diodes in circuit design. A practical switch design exhibits a certain amount of resistance in the on state and a finite resistance in the off state. A pin diode is an advancement of normal pn junction diode. The present state of sic power schottky and pin diodes are presented in this paper. Click here to go to our page on pin diode switches.
Pin diodes are available at mouser electronics from industry leading manufacturers. It is a silicon semicon ductor diode in which a high resistivity intrinsic i region is sandwiched between a ptype and ntype region. Pin diodessuperior building blocks for switch and attenuator applications. Chapter 2, the common pin diode switch configurations are presented, followed by sections comparing those features of pin diode switch designs for unique to high power microwave switches and high power lower frequency rfband switches. Pin diode working characteristics and its applications. Raditeks pin diode switches are an ideal choice for a variety of multiband telecommunication applications. The pin diode is used as an ideal radio frequency switch. When forward biased, the diode impedance is very low. The pn junction, when forward biased acts as close circuited and when reverse biased acts as open circuited.
The impedance of the diode is determined by its dc bias. The figure below shows a horizontal pin diode, sometimes called h pin. Pin diodes in rf switch applications pin diode spst switches figure 5 photo of the evaluation board for pin diode spst switch with bar6302l vias copper 35 figure 6 pcb stack information of the evaluation board for pin diode spst switch fr4, core, 0. Heres what is known as a vertical pin diode or v pin. Since the diode is in shunt with the rf path, the rf signal is attenuated when the diode is forward biased on, and is passed unattenuated when. The carrier lifetime in a pin diode controls the switching speed.
The high resistive layer of the intrinsic region provides the large electric field between the p and nregion. Pin diode type is preferred due to high powering handling abilities and fast switching speed 1. At full power i get about 1 volt rms across a 50 ohm resistor if i connect it instead of the preamp. In switch and attenuator applications, the pin diode should ideally control the rf signal level without introducing distortion which might change the shape of the. These products are excellent choices for your switch, limiter, phase shifter and attenuator circuit applications. These siliconbased pin diode switches are broadband by design, can operate with positive voltages and have been fully characterized for lowfrequency. Click here to go to our page on reflection attenuators. A high power solid state tr switch by gerald hiller and rick cory, skyworks solutions, inc. Pin diode can be used as rf and microwave switch, but in this case, the diode needs to be operated. Note that the cable length between the pin diode switch and the preamp is important. Thus, rectification at high voltage can be implemented with pin diode. Diode is a two terminal pn junction that can be used in various applications. Output current can be adjusted below the set value, by applying an external control signal to the vset pin. Sp8t pin diode switches pasternack enterprises, inc.
The pin diode is used as a dccontrolled microwave switch operated by rapid changes in bias or as a modulating device that takes advantage of the variable forwardresistance characteristic. Pin diodes in rf switch applications about this document scope and purpose this application note shows radio frequency rf switches for signal routing between different transmission paths with infineon pin diodes. A pin diode switch uses the pin diode as the nonlinear element low impedance, current in. At 320 mhz, the capacitive reactance of 1 pf is 497 ohms. Switches, digital and analog attenuators, and limiters each have unique functions that require proper device selection. The forward series resistance characteristic and the reverse capacitance characteristic are shown graphically in below figure for a typical pin diode.
Pin diode switches spdt switch spst switch low prices. The various switching modes available, principles of operation, operating characteristics and construction details are discussed. This monolithic pin diode switch offers broader band performance and smaller size. Mcli also offers high speed switching solution through our pin diode switch line.
The decision making process for pin diode selection for microwave switch design. Pin diode drive circuits optimized for fast switching chalmers. The use of rf and microwave switches based on pin diodes is widely spread. The electric field induces because of the movement of the holes and the electrons. Typically, the pin diode is used in rf through microwave frequency modulators and switches.
After the dc condition of the diode model has been determined that is, under forward or reverse bias condition, the pin diode intrinsic resistance r is fixed for all subsequent analyses. The lifetime of pin diodes is determined by design and is usually based on the desired switching speed. Sp8t pin diode switch designs feature excellent isolation levels up to 55 db, and extremely fast switching speed levels as low as 50 nsec. Micronote 703 silicon pin diode and gaas mesfet switches. Our silicon heterolithic microwave integrated circuit hmic pin diode process is ideal for high power and broadband switches operating from 50 mhz to 26 ghz. Adding a shunt pin diode in each switching branch improves the isolation provided by the switch. Introduction radio transceiver designers are always faced with a dilemma. Miwaves 911 series pin diode switches or mmic switch is a spst 912 series is spdt reflective switch that combines low loss, high isolation performance with an tegra ttl driver in a compact package. Furthermore, the internal ttl driver is offered as an option for ease ttl control. I searched the ltspice yahoo page and found a question by don huff w6jl with the same problem. Preferably the pin diodes are fabricated from gaas or other iiiv compound. Pin diode drive circuits optimized for fast switching. To order a spdt switch with center frequency of 60 ghz, 4 ghz bandwidth, 2. Each port or node is connected to receive a bias signal.
Compared to other surface mount packages, the design of the qfn package produces lower thermal resistance and also reduces the effects of the parasitic inductance of the anode bond wires. For this application, the rf switch load was a masw210b1 silicon pin diode spdt switch, used in the front end of a microwave downconverter figure 11. The aim of this work is the study and simulation of a sp4t switch based on pin diode dedicated to the umts use. Here the p and n layers are formed on top of the i layer.
The steadystate current, which sets the pin diode on resistance, is established by voltage differences across r11 and r12 and depends on the pin diode curves and system requirements. Pin diode working, characteristics, definition, applications. Radio transceiver designers have searched for a low cost solution to replace expensive mechanical switches and relays to direct high power transmit signals to the antenna and. Depending on the performance requirements, the switch can consist of all series diodes, all shunt diodes or a combination of series and shunt diodes. The smp4085lf pin diode is designed for shunt applications such as reflective switches or shuntdiode attenuator circuits. Pdf design a pin diode switch for highlinearity applications.
He was told his model needed a tt statement in it for pin behavior. In series diode switches, insertion loss is dependent on the series resistance of the pin diode while isolation. Radio transceiver designers have searched for a low cost solution to replace expensive mechanical switches and relays to direct high power transmit signals to the antenna and prevent that signal from entering the sensitive front. Cryogenicallycooled cband pin diode switch george h.
This switch will allow us to deliver rf energy via an output of four and will be integrated into a microstrip adaptive antenna array circuit. These pin diode switches are reflective type and can be tailored to absorptive type by integrating input and output isolators. The presence of intrinsic region exhibits high resistance property. In a radar system the switch directs transmit and receive signals to and from the. Mar 07, 2017 i was trying to do a pin diode tr switch in ltspice using a downloaded 1n4007 model but the diode didnt work like a pin. The necessity of using a highvoltage power pack to generate a high reverse bias in order to avoid limiting the. A tr switch may be configured using a series connected pin diode between the. Pin diodes are the workhorse of the solidstate microwave switch industry.
We can, on special request, provide single pole ninethrow pin diode switch sp9t, single pole tenthrow pin diode switch sp10t, single pole eleventhrow pin diode switch sp11t, singlepole twelvethrow pin diode switch sp12t and can array switches to form switch matrices to handle signal routing in complex systems. References 1,2 provide a fuller treatment of this subject and can be used as a basis for rf switch switch driver interface designs. Click here to go to our page on reflection phase shifters. Several modi cations was made to the driver design. The pin diode is a currentcontrolled resistor at radio and microwave frequencies.
Many types of diodes, such as pin and schottky diodes, or transistors operating in a linear regime, can be simulated by inserting into a schematic a suitable equivalent circuit usually provided by a. References 1,2 provide a fuller treatment of this subject and can be used as a basis for rf switch switch driver. The design, fabrication, and characterization of a a schottky diode, 4. For subsequent analyses, the depletion capacitance is not fixed at dc bias. For example, the capacitance of an offstate discrete pin diode might be 1 pf. The pin diode is a current controlled resistor at radio and microwave frequencies. Various driver options are available in higher isolation versions up to 60 db. The pin diode is an alteration of the pnjunction for particular applications. Pin diode switches 77 ghz sp4t and sp10t pin switches.
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