US20010007430A1 - High frequency MOSFET switch - Google Patents
High frequency MOSFET switch Download PDFInfo
- Publication number
- US20010007430A1 US20010007430A1 US09/780,199 US78019901A US2001007430A1 US 20010007430 A1 US20010007430 A1 US 20010007430A1 US 78019901 A US78019901 A US 78019901A US 2001007430 A1 US2001007430 A1 US 2001007430A1
- Authority
- US
- United States
- Prior art keywords
- coupled
- node
- transfer transistor
- transistor
- impedance element
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000012546 transfer Methods 0.000 claims abstract description 78
- 230000037361 pathway Effects 0.000 claims abstract description 22
- 230000003071 parasitic effect Effects 0.000 claims abstract description 8
- 230000008054 signal transmission Effects 0.000 claims description 22
- 230000008878 coupling Effects 0.000 claims description 8
- 238000010168 coupling process Methods 0.000 claims description 8
- 238000005859 coupling reaction Methods 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 7
- 230000001105 regulatory effect Effects 0.000 claims description 4
- 230000004913 activation Effects 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 description 13
- 239000004065 semiconductor Substances 0.000 description 9
- 230000004044 response Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 230000001419 dependent effect Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000007246 mechanism Effects 0.000 description 3
- 230000000644 propagated effect Effects 0.000 description 3
- 230000001902 propagating effect Effects 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000019491 signal transduction Effects 0.000 description 2
- 230000011664 signaling Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000000802 evaporation-induced self-assembly Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/04—Modifications for accelerating switching
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/16—Modifications for eliminating interference voltages or currents
- H03K17/161—Modifications for eliminating interference voltages or currents in field-effect transistor switches
- H03K17/162—Modifications for eliminating interference voltages or currents in field-effect transistor switches without feedback from the output circuit to the control circuit
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/04—Modifications for accelerating switching
- H03K17/041—Modifications for accelerating switching without feedback from the output circuit to the control circuit
- H03K17/0412—Modifications for accelerating switching without feedback from the output circuit to the control circuit by measures taken in the control circuit
- H03K17/04123—Modifications for accelerating switching without feedback from the output circuit to the control circuit by measures taken in the control circuit in field-effect transistor switches
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/687—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being field-effect transistors
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K2217/00—Indexing scheme related to electronic switching or gating, i.e. not by contact-making or -breaking covered by H03K17/00
- H03K2217/0018—Special modifications or use of the back gate voltage of a FET
Definitions
- the present invention relates to electronic switches.
- the present invention relates to semiconductor switches, including those formed of one or more metal-oxide-semiconductor field effect transistors (MOSFET). More particularly, the present invention relates to semiconductor switches capable of switching at relatively high frequencies, including those frequencies above about one gigahertz.
- MOSFET metal-oxide-semiconductor field effect transistors
- switches are widely used in many fields. They are used in all variety of large- and small-scale consumer products, including, but not limited to, automobiles and home electronics. They can be and are used as analog routers, gates, and relays. They are used as digital multiplexers, routers, and gates as well.
- FIG. 1 A generic P-type MOS transistor switch is shown in FIG. 1.
- the switch is essentially PMOS transistor M 1 having a source coupled to node A and a drain coupled to node B for the purpose of regulating signal transmission between nodes A and B.
- the control gate of switch M 1 is enabled by way of a coupling to enable-signal-input node EN from external control circuitry.
- EN is commonly coupled to the gate of M 1 by way of an inverter chain including one or more pairs of inverters such as inverters IV 1 and IV 2 .
- Inverters IV 1 and IV 2 are powered by a high-potential power rail identified as Vcc and a low-potential power rail identified as GND.
- the bulk of the switch transistor is coupled to the high-potential power rail.
- a logic LOW applied at EN propagates through the inverter chain to turn on M 1 , thereby allowing a signal to pass between nodes A and B, whether from A to B or from B to A.
- a logic HIGH at EN turns M 1 off, thereby blocking signal propagation between nodes A and B.
- line resistances R 1 and R 2 are shown, as are parasitic capacitances C 1 , C 2 , and C 3 .
- Resistances R 1 and R 2 represent the impedances associated with circuitry coupled to the transistor switch circuit. That impedance may be of some expected value; for example, in certain applications, resistances R 1 and R 2 are generally on the order of about 50 ohms. However, it is important to note that the present invention is not limited to any specific load impedances associated with external circuitry.
- capacitance C 1 represents the impedance associated with the gate-to-source interface of the transistor structure
- capacitance C 2 represents the impedance associated with the drain-to-gate interface of the transistor structure
- capacitance C 3 represents the impedance associated with the gate-to-bulk interface (typically a gate oxide layer) of the transistor structure.
- an N-type MOS transistor may be employed to perform a complimentary same switching function as that provided by PMOS transistor M 1 , with appropriate modifications in the inverter chain and the coupling of the bulk of the transistor to GND instead of Vcc, and bearing in mind certain differences understood by those skilled in the art in regard to NMOS and PMOS transistors.
- MOS transistors are desirable in that they consume very little power to operate. As fabrication techniques have advanced, the supply potentials and switching speeds at which such structures can operate effectively have improved. Nevertheless, it has been determined that most silicon MOS transistor switches configured in the manner shown in FIG. 1 have significant difficulty in propagating signals between A and B when such signals exceed transmission frequencies on the order of 400 MHz. It may appear to be possible to improve this characteristic by reducing the size of M 1 ; however, there is an undesirable trade-off involving an increase in the on-resistance of the transistor. Apart from an overall interest in keeping transistor on resistances low, the net result when evaluating the transfer function of the structure may be little or no gain in frequency performance.
- MOS transistor switches For most computing applications, the frequency limitations of MOS transistor switches are of little concern. However, as the drive for increased operating bandwidth capabilities grows, such as in the video transmission field for example, there is a greater need for MOS transistor switches that can pass relatively higher frequency transmissions with minimal losses. Therefore, what is needed is a semiconductor circuit that acts as a switch for digital and analog operations. What is also needed is a semiconductor switch circuit that is operable as a transfer gate or pass gate over an array of expected supply potentials. Further, what is needed is a MOSFET-based switch circuit capable of propagating relatively high frequency signals with minimal attenuation. What is further needed is such a switch circuit that propagates high-frequency transmissions with minimal effect on the on-resistance associated with the transistor circuit.
- an impedance element such as a resistive device, a capacitive device, or a combination thereof, is coupled between the gate of the pass gate transistor and a supply rail.
- the impedance element serves to decouple the pass gate transistor's gate from the supply rail that determines the gate potential.
- an impedance element may be coupled between the bulk of the pass gate transistor and the supply rail to which the bulk is coupled, again, to decouple that portion of the pass gate transistor from that particular supply rail.
- the bulk is ordinarily coupled directly to the high-potential rail, and for an NMOS transistor, the bulk is ordinarily coupled to the low-potential rail.
- an impedance that is greater than the impedance of the system is preferable to at least double the substantially unattenuated signal frequency that may propagate through the circuit of the present invention.
- the particular impedance employed may be selected as a function of the particular characteristics of the pass gate, the operating frequencies of interest, and the anticipated load on the circuit, among other factors. Additionally, it is to be noted that any nonzero impedance supplement will improve the response performance of the switch.
- the impedance element of the present invention is coupled in series with the parasitic capacitance pathways of the pass gate transistor so as to increase the overall impedance of those pathways.
- the prior shunt that those capacitance pathways established is substantially negated, particularly under those conditions where propagation of higher frequencies is of interest.
- the pass gate transistor circuit of the present invention permits signal transmission as expected for conventional complementary MOS (CMOS) switch devices.
- CMOS complementary MOS
- the present invention is suitable for use in a wide array of applications in which high-frequency switching is of interest.
- pass gate circuits effect the propagation of individual signals from one location to another. Ganged together, they can operate to propagate vast sets of signals in order to create data transmission systems that generate outcomes of increasing complexity.
- pass gate circuits may be used to form buses and backplanes that are interconnecting devices designed to enable the propagation of signals among discrete devices.
- Local or internal buses provide signal paths for propagation within a discrete device, such as a microprocessor. Types of local buses included in microprocessor systems include ISA, EISA, Micro Channel, VL-bus and PCI bus.
- buses to connect peripheral systems include NuBus, TURBOchannel, VMEbus, MULTIBUS and STD bus.
- Each such type of signal transmission system can operate only as effectively as the components used to create it.
- Improved pass gate circuits such as that of the present invention may be employed in any such bus, as well as backplane structures used to interconnect printed circuit boards, to increase propagation rates.
- interfaces such as Low Voltage Differential Signaling (LVDS), Transmission Minimized Differential Signaling (TMDS), Asynchronous Transfer Mode (ATM), and Digital Visual Interface (DVI) are designed to enable such transmissions.
- LVDS Low Voltage Differential Signaling
- TMDS Transmission Minimized Differential Signaling
- ATM Asynchronous Transfer Mode
- DVI Digital Visual Interface
- the present invention establishes the type of transmission bandwidth required for such interface standards.
- Increased propagation rates are of particular interest for the rapid transfer of dense data packets.
- Improved routers used to forward data packets from one location to another rely increasingly upon switch circuitry to enhance data transfer through local and wide area networks. This is particularly the case for high quality video, graphics, data, and voice transmissions passed by wire, optical and wireless connections.
- the routers are used to control the flow of signal traffic among devices and are dependent upon recognition of a variety of signal transmission protocols. Such protocols include, but are not limited to, IP, IPX, AppleTalk, DECnet.
- Improved switching circuitry such as the circuit of the present invention, facilitates and enhances the operation of such signal routers.
- the present invention is suitable for use in any computing system, such as personal computers, personal digital devices, telecommunications devices, and other electronic systems requiring rapid high quality signal propagation.
- FIG. 1 is a simplified schematic diagram of a prior-art transfer gate having a single enhancement-mode PMOS transistor as the transfer device.
- FIG. 2 is a simplified schematic block diagram of the high-frequency switch circuit of the present invention, showing a PMOS pass gate transistor coupled to a pair of impedance elements, all of which are couplable to an extended circuit.
- FIG. 3 is a simplified schematic block diagram of the high-frequency switch circuit of the present invention, showing an NMOS pass gate transistor coupled to a pair of impedance elements, all of which are coupleable to an extended circuit.
- FIG. 4 is a simplified circuit diagram of a first embodiment of the high-frequency switch circuit of FIG. 2, showing the impedance elements as resistive elements with control shunts.
- FIG. 5 is a simplified circuit diagram of a second embodiment of the high-frequency switch circuit of FIG. 2, showing the impedance elements as diode-wired MOS structures with control shunts.
- FIG. 6 is a Bode plot showing the frequency response of the high-frequency switch circuit of the present invention in comparison to the frequency response of the prior-art transfer circuit of FIG. 1.
- FIG. 7 is a simplified block representation of the switch circuit of the present invention forming part of a computer system, including as part of a bus and as part of a backplane.
- FIG. 8 is a simplified block representation of the switch circuit of the present invention forming part of a router.
- FIG. 9 is a simplified block representation of the switch circuit of the present invention forming part of a flat-panel screen display system.
- a high-frequency switch circuit 10 of the present invention is shown in FIG. 2.
- the circuit 10 includes an inverter stage 20 preferably formed of inverters IV 1 and IV 2 and PMOS pass gate transistor M 1 , much as in the prior-art switch shown in FIG. 1.
- the inverter stage 20 may be formed of a plurality of pairs of inverters, or some alternative form of enable signal propagation mechanism.
- the circuit 10 also includes a first impedance element 30 and a second impedance element 40 , wherein element 30 is coupled between the output of inverter stage 20 and the gate of M 1 and element 40 is coupled between the bulk of M 1 and high-potential power rail Vcc.
- An enable signal coming from a control circuit (not shown) by output enable node EN is preferably coupled to the input of the inverter stage 20 to substantially define the control of the operation of transistor M 1 by its gate.
- Inverters IV 1 and IV 2 are typically powered by high-potential rail Vcc and low-potential rail GND.
- the first impedance element 30 may be coupled to the gate of M 1 in an alternative manner, provided it acts to decouple that gate from the supply rail. The same can be said in regard to the coupling of second impedance element 40 .
- Transistor M 1 is the primary regulator of the transfer of a signal between nodes A and B. Either of node A or node B may be an input node or an output node, dependent upon the direction of the signal passing between external circuitry coupled to those two nodes. Elements 30 and 40 are designed to provide serial impedance between the gate of M 1 and the output of stage 20 and the bulk of M 1 and Vcc, respectively. The result is a relatively high-impedance pathway previously characterized by the parasitic capacitances of the transistor M 1 that otherwise would dominate at high frequencies of 350 MHz or more.
- FIG. 3 An equivalent high-frequency switch circuit 100 is shown in FIG. 3 for an NMOS pass gate transistor M 2 .
- the circuit 100 includes an inverter stage 120 preferably formed of inverter IV 1 and NMOS pass gate transistor M 2 .
- the inverter stage 120 may be formed of a plurality of an odd number of inverters, or some alternative form of enable signal propagation mechanism.
- the circuit 100 includes a first impedance element 130 and a second impedance element 140 , wherein element 130 is coupled between the output of inverter stage 120 and the gate of M 2 and element 140 is coupled between the bulk of M 1 and GND.
- An enable signal coming from a control circuit (not shown) by output enable node EN is preferably coupled to the input of the inverter stage 120 to substantially define the control of the operation of transistor M 2 by its gate.
- Vcc and GND typically power inverter IV 1 .
- Transistor M 2 is the primary regulator of the transfer of a signal between nodes A and B. Either of node A or node B may be an input node or an output node, dependent upon the direction of the signal passing between external circuitry coupled to those two nodes.
- Elements 130 and 140 are designed to provide serial impedance between the gate of M 2 and the output of stage 120 and the bulk of M 2 and GND, respectively. The result is a relatively high-impedance pathway previously characterized by the parasitic capacitances of the transistor M 2 that otherwise would dominate at relatively high frequencies of 350 MHz or more.
- FIG. 4 illustrates one preferred embodiment of the PMOS-based high-frequency switch circuit shown in FIG. 2.
- Circuit 10 ′ includes inverter stage 20 , first impedance element 30 , second impedance element 40 , and pass gate transistor M 1 .
- Impedance element 30 includes resistor R 3 having a high-potential node coupled to the output of IV 2 and a low-potential node coupled to the gate of M 1 .
- Element 30 further includes PMOS shunting control transistor M 3 having its gate coupled to the output of inverter IV 1 , its source coupled to Vcc, and its drain also coupled to the gate of M 1 .
- Impedance element 40 includes resistor R 4 having a high-potential node coupled to Vcc and a low-potential node coupled to the bulk of M 1 .
- Element 40 further includes PMOS shunting control transistor M 4 having its gate coupled to the output of inverter IV 1 , its source coupled to Vcc, and its drain coupled to the bulk of M 1 .
- Resistors R 3 and R 4 preferably have a resistance of about one kilohm each.
- the circuit 10 ′ of FIG. 4 provides relatively high impedance pathways at the gate and the bulk of M 1 that did not previously exist.
- the illustrated configuration effects a significant change in the frequency response of the circuit 10 ′ in comparison to that established by the prior-art circuit of FIG. 1.
- a logic LOW is applied to EN
- a logic HIGH is applied to the gates of transistors M 3 and M 4 by the output of IV 1 , thereby turning off those transistors and fixing the signal pathway to the gate and the bulk of M 1 .
- the LOW at EN results in a coupling of the gate and bulk of M 1 to GND through resistors R 3 and R 4 , respectively so that that pass gate transistor is on.
- the resistances of R 3 and R 4 are preferably established to ensure that the difference in the potentials of the gate and the bulk are sufficient to keep M 1 on to allow a signal to be propagated between nodes A and B without also developing a shunting parasitic impedance pathway in the transistor M 1 to GND, which is the reference for the potential drop across R 3 or R 4 .
- circuit 10 ′′ includes inverter stage 20 , first impedance element 30 , second impedance element 40 , and pass gate transistor M 1 , as previously shown.
- Impedance element 30 includes PMOS shunting control transistor M 3 coupled in the manner previously described with respect to circuit 10 ′ of FIG. 4, as well as transistor M 5 .
- NMOS transistor M 5 includes a gate coupled to the output of inverter IV 1 , a source coupled to the gate of M 1 , and a drain and a bulk coupled to GND.
- Impedance element 40 includes PMOS shunting control transistor M 4 coupled in the manner previously described with respect to circuit 10 ′ of FIG. 4, as well as transistor M 6 .
- PMOS transistor M 6 includes a gate coupled to the output of inverter IV 2 , a drain coupled to the bulk of M 1 , and a source and bulk coupled to Vcc.
- the circuit 10 ′′ of FIG. 5 provides relatively high impedance pathways at the gate and the bulk of M 1 that did not previously exist.
- the illustrated configuration effects a significant change in the frequency response of the circuit 10 ′′ in comparison to that established by the prior-art circuit of FIG. 1. Specifically, when a logic LOW is applied to EN, a logic HIGH is applied to the gates of transistors M 3 , M 4 , and M 5 by the output of IV 1 , thereby turning off transistors M 3 and M 4 and turning on transistor M 5 .
- the LOW at EN results in a coupling of the gate of M 1 to GND through transistors M 5 .
- the LOW at the output of inverter IV 2 turns on transistor M 6 so that the bulk of M 1 is coupled to Vcc, ensuring that pass gate transistor M 1 is on.
- the capacitances associated with transistors M 5 and M 6 provide sufficient impedance to ensure that the difference in the potentials of the gate and the bulk are sufficient to keep M 1 on to allow a signal to be propagated between nodes A and B without also developing a shunting parasitic impedance pathway.
- FIG. 6 is a Bode diagram showing the logarithmic drop-off in signal potential propagated through a pass gate circuit with respect to frequency changes.
- Waveform 200 represents the frequency response associated with the prior-art switch circuit of FIG. 1, while waveform 300 represents the frequency response associated with the high-frequency switch circuit 10 ′′ of FIG. 5.
- the figure shows the ⁇ 3 dB drop-off level. This drop-off level is a commonly used figure of merit used to describe the usable passband of a system.
- the associated ⁇ 3 dB frequency is about 350 MHz.
- the ⁇ 3 dB frequency is slightly more than about 900 MHz, an improvement of approximately more than 2.5 times.
- the switch circuit of the present invention may be employed as a conventional pass gate device having a pass through frequency bandwidth substantially greater than that available with prior MOS-based pass gate devices. It allows the gate and bulk potentials of transistor M 1 to change with the input signal at A or B rather than being coupled via a low-impedance path to Vcc or GND. It is to be understood that the switch circuit 10 may be suitable for use at frequencies exceeding 900 MHz, including well above 1 GHz, and is not intended to be limited to the representative example result presented in FIG. 6.
- the switch circuit 10 of the present invention may be employed in a variety of systems, as it is an effective mechanism for signal propagation in many applications including, but not limited to, internal and external data transmission, as well as video signal transmission.
- a computing system 100 including central processing unit 130 , a first memory cell 101 , a second memory cell 102 , an internal bus 103 , a first input/output port 104 , and a second input/output port 105 , interfaces with external devices, such as a keyboard 106 and a display 107 .
- Each of the devices identified may include a bus switch circuit 10 for each signal transmission line illustrated by way of example by lines 108 - 112 linking devices together for signal transmission. It is to be understood that those lines may represent wire, optical cable, and wireless connections.
- Box 120 is a simplified representation of one or more of the switch circuit 10 of the present invention employed for such signal transmission.
- FIG. 8 provides a simplified representation of a signal router 200 designed to analyze and direct signal traffic among a plurality of network systems 210 - 250 that represent either individual computing systems or networks of computing systems. The rate at which signal transmission occurs, and the quality of that signal, is dependent upon the switching circuitry employed.
- the router 200 may employ the switch circuit 10 of the present invention for each signal line of the interface system that connects the router 200 to the network systems 210 - 250 .
- Box 260 is a simplified representation of one or more of the switch circuit 10 of the present invention employed for such signal transmission. It may be employed by the router 200 as well as by any one or more of the network systems 210 - 250 .
- FIG. 9 provides a simplified representation of a flat panel display system 300 including a flat panel display 301 , a panel interface 302 that may employ LVDS technology, for example, an image scaler 303 , a frame rate converter 304 , a digital interface device 305 that may employ TMDS technology, for example, an analog interface device 306 , and a video decoder 307 . All may be coupled to a computer system 310 for data exchange and processing.
- the switch circuit 10 of the present invention is particularly suitable for the transmission of high-frequency digital signal transmissions, such as video signal transmissions. It may be employed in any one or more of the components of the flat panel display system 300 and in the computing system 310 .
- Box 320 is a simplified representation of one or more of the switch circuit 10 of the present invention employed for such signal transmission.
Abstract
Description
- 1. Field of the Invention
- The present invention relates to electronic switches. In particular, the present invention relates to semiconductor switches, including those formed of one or more metal-oxide-semiconductor field effect transistors (MOSFET). More particularly, the present invention relates to semiconductor switches capable of switching at relatively high frequencies, including those frequencies above about one gigahertz.
- 2. Description of the Prior Art
- Developments in semiconductor technology have created the capability to produce low-cost, highly reliable switches that are, effectively, implementations of mechanical relays. They have been found to be of particular use, when implemented, as single pole, single throw, type relays, but are not limited thereto. Semiconductor switches are being used more and more as replacements for the prior mechanical relays, due to the high switching speed available as well as their ability to transfer relatively high currents without failure. These switches are often referred to as transfer gates or pass transistors as they employ the characteristics of transistors—usually MOS transistors—to either permit or prevent the passage of a signal.
- It is well known that switches are widely used in many fields. They are used in all variety of large- and small-scale consumer products, including, but not limited to, automobiles and home electronics. They can be and are used as analog routers, gates, and relays. They are used as digital multiplexers, routers, and gates as well.
- A generic P-type MOS transistor switch is shown in FIG. 1. The switch is essentially PMOS transistor M1 having a source coupled to node A and a drain coupled to node B for the purpose of regulating signal transmission between nodes A and B. The control gate of switch M1 is enabled by way of a coupling to enable-signal-input node EN from external control circuitry. EN is commonly coupled to the gate of M1 by way of an inverter chain including one or more pairs of inverters such as inverters IV1 and IV2. Inverters IV1 and IV2 are powered by a high-potential power rail identified as Vcc and a low-potential power rail identified as GND. The bulk of the switch transistor is coupled to the high-potential power rail. In operation, a logic LOW applied at EN propagates through the inverter chain to turn on M1, thereby allowing a signal to pass between nodes A and B, whether from A to B or from B to A. A logic HIGH at EN turns M1 off, thereby blocking signal propagation between nodes A and B.
- For illustration purposes in order to advance the discussion of the present invention, line resistances R1 and R2 are shown, as are parasitic capacitances C1, C2, and C3. Resistances R1 and R2 represent the impedances associated with circuitry coupled to the transistor switch circuit. That impedance may be of some expected value; for example, in certain applications, resistances R1 and R2 are generally on the order of about 50 ohms. However, it is important to note that the present invention is not limited to any specific load impedances associated with external circuitry.
- Continuing the discussion regarding FIG. 1, capacitance C1 represents the impedance associated with the gate-to-source interface of the transistor structure, capacitance C2 represents the impedance associated with the drain-to-gate interface of the transistor structure, and capacitance C3 represents the impedance associated with the gate-to-bulk interface (typically a gate oxide layer) of the transistor structure. It is to be noted that an N-type MOS transistor may be employed to perform a complimentary same switching function as that provided by PMOS transistor M1, with appropriate modifications in the inverter chain and the coupling of the bulk of the transistor to GND instead of Vcc, and bearing in mind certain differences understood by those skilled in the art in regard to NMOS and PMOS transistors.
- MOS transistors are desirable in that they consume very little power to operate. As fabrication techniques have advanced, the supply potentials and switching speeds at which such structures can operate effectively have improved. Nevertheless, it has been determined that most silicon MOS transistor switches configured in the manner shown in FIG. 1 have significant difficulty in propagating signals between A and B when such signals exceed transmission frequencies on the order of 400 MHz. It may appear to be possible to improve this characteristic by reducing the size of M1; however, there is an undesirable trade-off involving an increase in the on-resistance of the transistor. Apart from an overall interest in keeping transistor on resistances low, the net result when evaluating the transfer function of the structure may be little or no gain in frequency performance.
- An analysis of the impedances of the switch transistor shown in FIG. 1 leads to an understanding of the propagation frequency limitation associated with that device. Specifically, as the transmission signal propagation frequency exceeds 300 MHz, for example, the impedances associated with the characteristic of the system identified simply by resistances R1 and R2, and the gate-coupled capacitances C1, C2, and C3 begin to dominate the transfer function. As a result, at such a frequency and higher, a shunt or short is established between the transistor's bulk coupled to Vcc and GND (through inverter IV2 that enables M1). The dominating impedance at such frequencies causes an unacceptable attenuation of the signal to be passed. As earlier noted, this cannot be resolved by reducing the gate size of M1 as that drives up the drain-source resistance undesirably.
- For most computing applications, the frequency limitations of MOS transistor switches are of little concern. However, as the drive for increased operating bandwidth capabilities grows, such as in the video transmission field for example, there is a greater need for MOS transistor switches that can pass relatively higher frequency transmissions with minimal losses. Therefore, what is needed is a semiconductor circuit that acts as a switch for digital and analog operations. What is also needed is a semiconductor switch circuit that is operable as a transfer gate or pass gate over an array of expected supply potentials. Further, what is needed is a MOSFET-based switch circuit capable of propagating relatively high frequency signals with minimal attenuation. What is further needed is such a switch circuit that propagates high-frequency transmissions with minimal effect on the on-resistance associated with the transistor circuit.
- It is an object of the present invention to provide a semiconductor circuit that acts as a switch for digital and analog operations. It is also an object of the present invention to provide a semiconductor switch that is a transfer gate or pass gate operable for a broad range of supply potentials. It is a further object of the present invention to provide a MOSFET-based switch circuit capable of propagating relatively high frequency signals with minimal attenuation. Another object of the present invention is to provide such a switch circuit that propagates high-frequency transmissions with minimal effect on the on-resistance associated with the MOSFET-based passgate structure.
- These and other objectives are achieved in the present invention by increasing the impedance of the shunting pathway associated with the existing MOSFET structure used to establish the pass gate. Specifically, an impedance element, such as a resistive device, a capacitive device, or a combination thereof, is coupled between the gate of the pass gate transistor and a supply rail. The impedance element serves to decouple the pass gate transistor's gate from the supply rail that determines the gate potential. Additionally, such an impedance element may be coupled between the bulk of the pass gate transistor and the supply rail to which the bulk is coupled, again, to decouple that portion of the pass gate transistor from that particular supply rail. For a PMOS transistor, the bulk is ordinarily coupled directly to the high-potential rail, and for an NMOS transistor, the bulk is ordinarily coupled to the low-potential rail. It has been determined that for a conventional MOS transistor structure employed as the pass gate transistor, an impedance that is greater than the impedance of the system is preferable to at least double the substantially unattenuated signal frequency that may propagate through the circuit of the present invention. Of course, the particular impedance employed may be selected as a function of the particular characteristics of the pass gate, the operating frequencies of interest, and the anticipated load on the circuit, among other factors. Additionally, it is to be noted that any nonzero impedance supplement will improve the response performance of the switch.
- The impedance element of the present invention is coupled in series with the parasitic capacitance pathways of the pass gate transistor so as to increase the overall impedance of those pathways. As a result, the prior shunt that those capacitance pathways established is substantially negated, particularly under those conditions where propagation of higher frequencies is of interest. In all other respects the pass gate transistor circuit of the present invention permits signal transmission as expected for conventional complementary MOS (CMOS) switch devices.
- The present invention is suitable for use in a wide array of applications in which high-frequency switching is of interest. On the most fundamental level, pass gate circuits effect the propagation of individual signals from one location to another. Ganged together, they can operate to propagate vast sets of signals in order to create data transmission systems that generate outcomes of increasing complexity. On a basic level, pass gate circuits may be used to form buses and backplanes that are interconnecting devices designed to enable the propagation of signals among discrete devices. Local or internal buses provide signal paths for propagation within a discrete device, such as a microprocessor. Types of local buses included in microprocessor systems include ISA, EISA, Micro Channel, VL-bus and PCI bus. Examples of buses to connect peripheral systems, such as printers, keyboards, and the like, include NuBus, TURBOchannel, VMEbus, MULTIBUS and STD bus. Each such type of signal transmission system can operate only as effectively as the components used to create it. Improved pass gate circuits such as that of the present invention may be employed in any such bus, as well as backplane structures used to interconnect printed circuit boards, to increase propagation rates. For video and graphics signal transmissions, including for flat screen panels in particular, interfaces such as Low Voltage Differential Signaling (LVDS), Transmission Minimized Differential Signaling (TMDS), Asynchronous Transfer Mode (ATM), and Digital Visual Interface (DVI) are designed to enable such transmissions. The present invention establishes the type of transmission bandwidth required for such interface standards.
- Increased propagation rates are of particular interest for the rapid transfer of dense data packets. Improved routers used to forward data packets from one location to another rely increasingly upon switch circuitry to enhance data transfer through local and wide area networks. This is particularly the case for high quality video, graphics, data, and voice transmissions passed by wire, optical and wireless connections. The routers are used to control the flow of signal traffic among devices and are dependent upon recognition of a variety of signal transmission protocols. Such protocols include, but are not limited to, IP, IPX, AppleTalk, DECnet. Improved switching circuitry such as the circuit of the present invention, facilitates and enhances the operation of such signal routers. Of course, the present invention is suitable for use in any computing system, such as personal computers, personal digital devices, telecommunications devices, and other electronic systems requiring rapid high quality signal propagation.
- These and other advantages of the present invention will become apparent upon review of the following detailed description of the embodiments of the invention, the accompanying drawings, and the appended claims.
- FIG. 1 is a simplified schematic diagram of a prior-art transfer gate having a single enhancement-mode PMOS transistor as the transfer device.
- FIG. 2 is a simplified schematic block diagram of the high-frequency switch circuit of the present invention, showing a PMOS pass gate transistor coupled to a pair of impedance elements, all of which are couplable to an extended circuit.
- FIG. 3 is a simplified schematic block diagram of the high-frequency switch circuit of the present invention, showing an NMOS pass gate transistor coupled to a pair of impedance elements, all of which are coupleable to an extended circuit.
- FIG. 4 is a simplified circuit diagram of a first embodiment of the high-frequency switch circuit of FIG. 2, showing the impedance elements as resistive elements with control shunts.
- FIG. 5 is a simplified circuit diagram of a second embodiment of the high-frequency switch circuit of FIG. 2, showing the impedance elements as diode-wired MOS structures with control shunts.
- FIG. 6 is a Bode plot showing the frequency response of the high-frequency switch circuit of the present invention in comparison to the frequency response of the prior-art transfer circuit of FIG. 1.
- FIG. 7 is a simplified block representation of the switch circuit of the present invention forming part of a computer system, including as part of a bus and as part of a backplane.
- FIG. 8 is a simplified block representation of the switch circuit of the present invention forming part of a router.
- FIG. 9 is a simplified block representation of the switch circuit of the present invention forming part of a flat-panel screen display system.
- A high-
frequency switch circuit 10 of the present invention is shown in FIG. 2. Thecircuit 10 includes aninverter stage 20 preferably formed of inverters IV1 and IV2 and PMOS pass gate transistor M1, much as in the prior-art switch shown in FIG. 1. Of course, theinverter stage 20 may be formed of a plurality of pairs of inverters, or some alternative form of enable signal propagation mechanism. Thecircuit 10 also includes afirst impedance element 30 and asecond impedance element 40, whereinelement 30 is coupled between the output ofinverter stage 20 and the gate of M1 andelement 40 is coupled between the bulk of M1 and high-potential power rail Vcc. An enable signal coming from a control circuit (not shown) by output enable node EN is preferably coupled to the input of theinverter stage 20 to substantially define the control of the operation of transistor M1 by its gate. Inverters IV1 and IV2 are typically powered by high-potential rail Vcc and low-potential rail GND. It is to be noted that thefirst impedance element 30 may be coupled to the gate of M1 in an alternative manner, provided it acts to decouple that gate from the supply rail. The same can be said in regard to the coupling ofsecond impedance element 40. - Transistor M1 is the primary regulator of the transfer of a signal between nodes A and B. Either of node A or node B may be an input node or an output node, dependent upon the direction of the signal passing between external circuitry coupled to those two nodes.
Elements stage 20 and the bulk of M1 and Vcc, respectively. The result is a relatively high-impedance pathway previously characterized by the parasitic capacitances of the transistor M1 that otherwise would dominate at high frequencies of 350 MHz or more. - An equivalent high-
frequency switch circuit 100 is shown in FIG. 3 for an NMOS pass gate transistor M2. Thecircuit 100 includes aninverter stage 120 preferably formed of inverter IV1 and NMOS pass gate transistor M2. Of course, theinverter stage 120 may be formed of a plurality of an odd number of inverters, or some alternative form of enable signal propagation mechanism. Additionally, thecircuit 100 includes afirst impedance element 130 and asecond impedance element 140, whereinelement 130 is coupled between the output ofinverter stage 120 and the gate of M2 andelement 140 is coupled between the bulk of M1 and GND. An enable signal coming from a control circuit (not shown) by output enable node EN is preferably coupled to the input of theinverter stage 120 to substantially define the control of the operation of transistor M2 by its gate. Vcc and GND typically power inverter IV1. Transistor M2 is the primary regulator of the transfer of a signal between nodes A and B. Either of node A or node B may be an input node or an output node, dependent upon the direction of the signal passing between external circuitry coupled to those two nodes.Elements stage 120 and the bulk of M2 and GND, respectively. The result is a relatively high-impedance pathway previously characterized by the parasitic capacitances of the transistor M2 that otherwise would dominate at relatively high frequencies of 350 MHz or more. - FIG. 4 illustrates one preferred embodiment of the PMOS-based high-frequency switch circuit shown in FIG. 2.
Circuit 10′ includesinverter stage 20,first impedance element 30,second impedance element 40, and pass gate transistor M1.Impedance element 30 includes resistor R3 having a high-potential node coupled to the output of IV2 and a low-potential node coupled to the gate of M1.Element 30 further includes PMOS shunting control transistor M3 having its gate coupled to the output of inverter IV1, its source coupled to Vcc, and its drain also coupled to the gate of M1.Impedance element 40 includes resistor R4 having a high-potential node coupled to Vcc and a low-potential node coupled to the bulk of M1.Element 40 further includes PMOS shunting control transistor M4 having its gate coupled to the output of inverter IV1, its source coupled to Vcc, and its drain coupled to the bulk of M1. Resistors R3 and R4 preferably have a resistance of about one kilohm each. - In operation, the
circuit 10′ of FIG. 4 provides relatively high impedance pathways at the gate and the bulk of M1 that did not previously exist. The illustrated configuration effects a significant change in the frequency response of thecircuit 10′ in comparison to that established by the prior-art circuit of FIG. 1. Specifically, when a logic LOW is applied to EN, a logic HIGH is applied to the gates of transistors M3 and M4 by the output of IV1, thereby turning off those transistors and fixing the signal pathway to the gate and the bulk of M1. The LOW at EN results in a coupling of the gate and bulk of M1 to GND through resistors R3 and R4, respectively so that that pass gate transistor is on. The resistances of R3 and R4 are preferably established to ensure that the difference in the potentials of the gate and the bulk are sufficient to keep M1 on to allow a signal to be propagated between nodes A and B without also developing a shunting parasitic impedance pathway in the transistor M1 to GND, which is the reference for the potential drop across R3 or R4. - Completing the description of the operation of the
circuit 10′ of FIG. 4, when a logic HIGH is applied to EN, a logic LOW is applied to the gates of transistors M3 and M4 by the output of IV1, thereby turning on those transistors and fixing the signal pathway to the gate and the bulk of M1 to the potential of Vcc. The HIGH at EN results in a coupling of the gate and bulk of M1 to Vcc through transistors M3 and M4, respectively so that that pass gate transistor is off. With transistors M3 and M4 on, transistor M1 will remain off, as that is the pathway with the lower impedance. - A second preferred embodiment of the high-frequency switch circuit of the present invention shown in FIG. 2 is shown as
circuit 10″ in FIG. 5.Circuit 10″ includesinverter stage 20,first impedance element 30,second impedance element 40, and pass gate transistor M1, as previously shown.Impedance element 30 includes PMOS shunting control transistor M3 coupled in the manner previously described with respect tocircuit 10′ of FIG. 4, as well as transistor M5. NMOS transistor M5 includes a gate coupled to the output of inverter IV1, a source coupled to the gate of M1, and a drain and a bulk coupled to GND.Impedance element 40 includes PMOS shunting control transistor M4 coupled in the manner previously described with respect tocircuit 10′ of FIG. 4, as well as transistor M6. PMOS transistor M6 includes a gate coupled to the output of inverter IV2, a drain coupled to the bulk of M1, and a source and bulk coupled to Vcc. - In operation, the
circuit 10″ of FIG. 5 provides relatively high impedance pathways at the gate and the bulk of M1 that did not previously exist. The illustrated configuration effects a significant change in the frequency response of thecircuit 10″ in comparison to that established by the prior-art circuit of FIG. 1. Specifically, when a logic LOW is applied to EN, a logic HIGH is applied to the gates of transistors M3, M4, and M5 by the output of IV1, thereby turning off transistors M3 and M4 and turning on transistor M5. The LOW at EN results in a coupling of the gate of M1 to GND through transistors M5. Additionally, the LOW at the output of inverter IV2 turns on transistor M6 so that the bulk of M1 is coupled to Vcc, ensuring that pass gate transistor M1 is on. The capacitances associated with transistors M5 and M6 provide sufficient impedance to ensure that the difference in the potentials of the gate and the bulk are sufficient to keep M1 on to allow a signal to be propagated between nodes A and B without also developing a shunting parasitic impedance pathway. - Completing the description of the operation of the
circuit 10″ of FIG. 5, when a logic HIGH is applied to EN, a logic LOW is applied to the gates of transistors M3, M4, and M5 by the output of IV1, thereby turning on transistors M3 and M4 and turning off transistor M5. The HIGH at EN results in a coupling of the gate of M1 to Vcc through transistor M3 so that that pass gate transistor is off. Additionally, the HIGH at the output of inverter IV2 turns off transistor M6 so that the bulk of M1 is coupled to Vcc, ensuring that pass gate transistor M1 is off. With transistors M3 and M4 on, transistor M1 will remain off, as that is the pathway with the lower impedance. - The advantage associated with the introduction of the
impedance elements Waveform 200 represents the frequency response associated with the prior-art switch circuit of FIG. 1, whilewaveform 300 represents the frequency response associated with the high-frequency switch circuit 10″ of FIG. 5. The figure shows the −3 dB drop-off level. This drop-off level is a commonly used figure of merit used to describe the usable passband of a system. For the prior-art circuit represented bywaveform 200, the associated −3 dB frequency is about 350 MHz. For theswitch circuit 10″ of the present invention, the −3 dB frequency is slightly more than about 900 MHz, an improvement of approximately more than 2.5 times. It can be seen that the switch circuit of the present invention may be employed as a conventional pass gate device having a pass through frequency bandwidth substantially greater than that available with prior MOS-based pass gate devices. It allows the gate and bulk potentials of transistor M1 to change with the input signal at A or B rather than being coupled via a low-impedance path to Vcc or GND. It is to be understood that theswitch circuit 10 may be suitable for use at frequencies exceeding 900 MHz, including well above 1 GHz, and is not intended to be limited to the representative example result presented in FIG. 6. - As previously noted, the
switch circuit 10 of the present invention may be employed in a variety of systems, as it is an effective mechanism for signal propagation in many applications including, but not limited to, internal and external data transmission, as well as video signal transmission. As illustrated in FIG. 7, acomputing system 100 includingcentral processing unit 130, afirst memory cell 101, a second memory cell 102, aninternal bus 103, a first input/output port 104, and a second input/output port 105, interfaces with external devices, such as a keyboard 106 and adisplay 107. Each of the devices identified may include abus switch circuit 10 for each signal transmission line illustrated by way of example by lines 108-112 linking devices together for signal transmission. It is to be understood that those lines may represent wire, optical cable, and wireless connections.Box 120 is a simplified representation of one or more of theswitch circuit 10 of the present invention employed for such signal transmission. - FIG. 8 provides a simplified representation of a
signal router 200 designed to analyze and direct signal traffic among a plurality of network systems 210-250 that represent either individual computing systems or networks of computing systems. The rate at which signal transmission occurs, and the quality of that signal, is dependent upon the switching circuitry employed. Therouter 200 may employ theswitch circuit 10 of the present invention for each signal line of the interface system that connects therouter 200 to the network systems 210-250.Box 260 is a simplified representation of one or more of theswitch circuit 10 of the present invention employed for such signal transmission. It may be employed by therouter 200 as well as by any one or more of the network systems 210-250. - FIG. 9 provides a simplified representation of a flat
panel display system 300 including aflat panel display 301, apanel interface 302 that may employ LVDS technology, for example, animage scaler 303, a frame rate converter 304, adigital interface device 305 that may employ TMDS technology, for example, ananalog interface device 306, and avideo decoder 307. All may be coupled to acomputer system 310 for data exchange and processing. Theswitch circuit 10 of the present invention is particularly suitable for the transmission of high-frequency digital signal transmissions, such as video signal transmissions. It may be employed in any one or more of the components of the flatpanel display system 300 and in thecomputing system 310. Box 320 is a simplified representation of one or more of theswitch circuit 10 of the present invention employed for such signal transmission. - While the present invention has been described with specific reference to particular embodiments, it is to be understood that all modifications, variants, and equivalents are deemed to be within the scope of the following appended claims.
Claims (33)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/780,199 US6396325B2 (en) | 1999-12-03 | 2001-02-09 | High frequency MOSFET switch |
TW091101484A TW565999B (en) | 2001-02-09 | 2002-01-29 | High frequency MOSFET switch |
KR1020020005562A KR100886011B1 (en) | 2001-02-09 | 2002-01-31 | High frequency mosfet switch |
DE2002103955 DE10203955A1 (en) | 2001-02-09 | 2002-02-01 | High-frequency switch circuit for digital and analog operations, has impedance element to negate low-parasitic capacitance associated with transfer transistor |
JP2002031997A JP4230704B2 (en) | 2001-02-09 | 2002-02-08 | High frequency MOSFET switch |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US45470999A | 1999-12-03 | 1999-12-03 | |
US09/780,199 US6396325B2 (en) | 1999-12-03 | 2001-02-09 | High frequency MOSFET switch |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US45470999A Continuation-In-Part | 1999-12-03 | 1999-12-03 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20010007430A1 true US20010007430A1 (en) | 2001-07-12 |
US6396325B2 US6396325B2 (en) | 2002-05-28 |
Family
ID=25118919
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/780,199 Expired - Lifetime US6396325B2 (en) | 1999-12-03 | 2001-02-09 | High frequency MOSFET switch |
Country Status (5)
Country | Link |
---|---|
US (1) | US6396325B2 (en) |
JP (1) | JP4230704B2 (en) |
KR (1) | KR100886011B1 (en) |
DE (1) | DE10203955A1 (en) |
TW (1) | TW565999B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050276261A1 (en) * | 2004-06-09 | 2005-12-15 | Rambus, Inc. | Communication channel calibration using feedback |
US20060091932A1 (en) * | 2004-11-02 | 2006-05-04 | Rambus Inc. | Pass transistors with minimized capacitive loading |
US20070085627A1 (en) * | 2003-12-17 | 2007-04-19 | Wilhelm Kraemer | Electronic high-frequency switch and attenuator with said high-frequency switches |
US7259589B1 (en) | 2005-09-16 | 2007-08-21 | Pericom Semiconductor Corp. | Visual or multimedia interface bus switch with level-shifted ground and input protection against non-compliant transmission-minimized differential signaling (TMDS) transmitter |
US11088685B2 (en) * | 2017-07-03 | 2021-08-10 | Mitsubishi Electric Corporation | High-frequency switch |
Families Citing this family (38)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6563367B1 (en) * | 2000-08-16 | 2003-05-13 | Altera Corporation | Interconnection switch structures |
US6661253B1 (en) | 2000-08-16 | 2003-12-09 | Altera Corporation | Passgate structures for use in low-voltage applications |
US7027072B1 (en) | 2000-10-13 | 2006-04-11 | Silicon Graphics, Inc. | Method and system for spatially compositing digital video images with a tile pattern library |
US7358974B2 (en) * | 2001-01-29 | 2008-04-15 | Silicon Graphics, Inc. | Method and system for minimizing an amount of data needed to test data against subarea boundaries in spatially composited digital video |
US7145378B2 (en) * | 2001-07-16 | 2006-12-05 | Fairchild Semiconductor Corporation | Configurable switch with selectable level shifting |
US6804502B2 (en) | 2001-10-10 | 2004-10-12 | Peregrine Semiconductor Corporation | Switch circuit and method of switching radio frequency signals |
TW557435B (en) * | 2002-05-08 | 2003-10-11 | Via Tech Inc | Portable computer capable of displaying input image signal |
US7034837B2 (en) * | 2003-05-05 | 2006-04-25 | Silicon Graphics, Inc. | Method, system, and computer program product for determining a structure of a graphics compositor tree |
EP3570374B1 (en) | 2004-06-23 | 2022-04-20 | pSemi Corporation | Integrated rf front end |
US7292065B2 (en) * | 2004-08-03 | 2007-11-06 | Altera Corporation | Enhanced passgate structures for reducing leakage current |
JP4599225B2 (en) * | 2005-05-26 | 2010-12-15 | 株式会社東芝 | Switching circuit |
US8742502B2 (en) | 2005-07-11 | 2014-06-03 | Peregrine Semiconductor Corporation | Method and apparatus for use in improving linearity of MOSFETs using an accumulated charge sink-harmonic wrinkle reduction |
US7910993B2 (en) | 2005-07-11 | 2011-03-22 | Peregrine Semiconductor Corporation | Method and apparatus for use in improving linearity of MOSFET's using an accumulated charge sink |
USRE48965E1 (en) | 2005-07-11 | 2022-03-08 | Psemi Corporation | Method and apparatus improving gate oxide reliability by controlling accumulated charge |
US7890891B2 (en) | 2005-07-11 | 2011-02-15 | Peregrine Semiconductor Corporation | Method and apparatus improving gate oxide reliability by controlling accumulated charge |
US20080076371A1 (en) | 2005-07-11 | 2008-03-27 | Alexander Dribinsky | Circuit and method for controlling charge injection in radio frequency switches |
US9653601B2 (en) | 2005-07-11 | 2017-05-16 | Peregrine Semiconductor Corporation | Method and apparatus for use in improving linearity of MOSFETs using an accumulated charge sink-harmonic wrinkle reduction |
US7890063B2 (en) * | 2006-10-03 | 2011-02-15 | Samsung Electro-Mechanics | Systems, methods, and apparatuses for complementary metal oxide semiconductor (CMOS) antenna switches using body switching in multistacking structure |
US7843280B2 (en) * | 2006-12-01 | 2010-11-30 | Samsung Electro-Mechanics Company | Systems, methods, and apparatuses for high power complementary metal oxide semiconductor (CMOS) antenna switches using body switching and substrate junction diode controlling in multistacking structure |
DE102006058169A1 (en) * | 2006-12-09 | 2008-06-19 | Atmel Germany Gmbh | Integrated semiconductor circuit |
JP5151145B2 (en) | 2006-12-26 | 2013-02-27 | ソニー株式会社 | Switch circuit, variable capacitor circuit and its IC |
US7738841B2 (en) * | 2007-09-14 | 2010-06-15 | Samsung Electro-Mechanics | Systems, methods and apparatuses for high power complementary metal oxide semiconductor (CMOS) antenna switches using body switching and external component in multi-stacking structure |
US8299835B2 (en) * | 2008-02-01 | 2012-10-30 | Sensor Electronic Technology, Inc. | Radio-frequency switch circuit with separately controlled shunt switching device |
EP2255443B1 (en) | 2008-02-28 | 2012-11-28 | Peregrine Semiconductor Corporation | Method and apparatus for use in digitally tuning a capacitor in an integrated circuit device |
US7928794B2 (en) * | 2008-07-21 | 2011-04-19 | Analog Devices, Inc. | Method and apparatus for a dynamically self-bootstrapped switch |
US8723260B1 (en) | 2009-03-12 | 2014-05-13 | Rf Micro Devices, Inc. | Semiconductor radio frequency switch with body contact |
US8514008B2 (en) * | 2010-07-28 | 2013-08-20 | Qualcomm, Incorporated | RF isolation switch circuit |
US8115518B1 (en) * | 2010-08-16 | 2012-02-14 | Analog Devices, Inc. | Integrated circuit for reducing nonlinearity in sampling networks |
US9590674B2 (en) | 2012-12-14 | 2017-03-07 | Peregrine Semiconductor Corporation | Semiconductor devices with switchable ground-body connection |
US20150236798A1 (en) | 2013-03-14 | 2015-08-20 | Peregrine Semiconductor Corporation | Methods for Increasing RF Throughput Via Usage of Tunable Filters |
US9406695B2 (en) | 2013-11-20 | 2016-08-02 | Peregrine Semiconductor Corporation | Circuit and method for improving ESD tolerance and switching speed |
US9966946B2 (en) * | 2014-04-02 | 2018-05-08 | Infineon Technologies Ag | System and method for a driving a radio frequency switch |
US9831857B2 (en) | 2015-03-11 | 2017-11-28 | Peregrine Semiconductor Corporation | Power splitter with programmable output phase shift |
US9948281B2 (en) | 2016-09-02 | 2018-04-17 | Peregrine Semiconductor Corporation | Positive logic digitally tunable capacitor |
US10886911B2 (en) | 2018-03-28 | 2021-01-05 | Psemi Corporation | Stacked FET switch bias ladders |
US10236872B1 (en) | 2018-03-28 | 2019-03-19 | Psemi Corporation | AC coupling modules for bias ladders |
US10505530B2 (en) | 2018-03-28 | 2019-12-10 | Psemi Corporation | Positive logic switch with selectable DC blocking circuit |
US11476849B2 (en) | 2020-01-06 | 2022-10-18 | Psemi Corporation | High power positive logic switch |
Family Cites Families (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3872325A (en) * | 1973-10-17 | 1975-03-18 | Rca Corp | R-F switching circuit |
DE2851789C2 (en) * | 1978-11-30 | 1981-10-01 | Licentia Patent-Verwaltungs-Gmbh, 6000 Frankfurt | Circuit for switching and transmitting alternating voltages |
US4508983A (en) * | 1983-02-10 | 1985-04-02 | Motorola, Inc. | MOS Analog switch driven by complementary, minimally skewed clock signals |
US4787686A (en) * | 1985-12-20 | 1988-11-29 | Raytheon Company | Monolithic programmable attenuator |
JPH0773202B2 (en) * | 1989-12-28 | 1995-08-02 | 三菱電機株式会社 | Semiconductor integrated circuit |
JPH0595266A (en) * | 1991-09-30 | 1993-04-16 | Rohm Co Ltd | Transmission gate |
US5461265A (en) * | 1992-05-25 | 1995-10-24 | Matsushita Electric Industrial Co., Ltd. | High-frequency variable impedance circuit having improved linearity of operating characteristics |
JP3198808B2 (en) * | 1994-06-30 | 2001-08-13 | 株式会社村田製作所 | High frequency switch |
US5903178A (en) * | 1994-12-16 | 1999-05-11 | Matsushita Electronics Corporation | Semiconductor integrated circuit |
JPH08204530A (en) * | 1995-01-23 | 1996-08-09 | Sony Corp | Switch circuit |
US5883541A (en) * | 1997-03-05 | 1999-03-16 | Nec Corporation | High frequency switching circuit |
JP3258930B2 (en) * | 1997-04-24 | 2002-02-18 | 東芝マイクロエレクトロニクス株式会社 | Transmission gate |
US6052000A (en) * | 1997-04-30 | 2000-04-18 | Texas Instruments Incorporated | MOS sample and hold circuit |
US5900657A (en) * | 1997-05-19 | 1999-05-04 | National Semiconductor Corp. | MOS switch that reduces clock feed through in a switched capacitor circuit |
JP3310203B2 (en) * | 1997-07-25 | 2002-08-05 | 株式会社東芝 | High frequency switch device |
US6281737B1 (en) * | 1998-11-20 | 2001-08-28 | International Business Machines Corporation | Method and apparatus for reducing parasitic bipolar current in a silicon-on-insulator transistor |
US6236259B1 (en) * | 1999-10-04 | 2001-05-22 | Fairchild Semiconductor Corporation | Active undershoot hardened fet switch |
-
2001
- 2001-02-09 US US09/780,199 patent/US6396325B2/en not_active Expired - Lifetime
-
2002
- 2002-01-29 TW TW091101484A patent/TW565999B/en not_active IP Right Cessation
- 2002-01-31 KR KR1020020005562A patent/KR100886011B1/en active IP Right Grant
- 2002-02-01 DE DE2002103955 patent/DE10203955A1/en not_active Withdrawn
- 2002-02-08 JP JP2002031997A patent/JP4230704B2/en not_active Expired - Fee Related
Cited By (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7489179B2 (en) * | 2003-12-17 | 2009-02-10 | Rohde & Schwarz Gmbh & Co., Kg | Electronic high-frequency switch and attenuator with said high-frequency switches |
US20070085627A1 (en) * | 2003-12-17 | 2007-04-19 | Wilhelm Kraemer | Electronic high-frequency switch and attenuator with said high-frequency switches |
US9172521B2 (en) | 2004-06-09 | 2015-10-27 | Rambus Inc. | Communication channel calibration using feedback |
US20090132741A1 (en) * | 2004-06-09 | 2009-05-21 | Rambus, Inc. | Communication channel calibration using feedback |
US20050276261A1 (en) * | 2004-06-09 | 2005-12-15 | Rambus, Inc. | Communication channel calibration using feedback |
US8121803B2 (en) | 2004-06-09 | 2012-02-21 | Rambus, Inc. | Communication channel calibration using feedback |
US7516029B2 (en) | 2004-06-09 | 2009-04-07 | Rambus, Inc. | Communication channel calibration using feedback |
US9735898B2 (en) | 2004-06-09 | 2017-08-15 | Rambus Inc. | Communication channel calibration using feedback |
US10439740B2 (en) | 2004-06-09 | 2019-10-08 | Rambus Inc. | Communication channel calibration using feedback |
US11128388B2 (en) | 2004-06-09 | 2021-09-21 | Rambus Inc. | Communication channel calibration using feedback |
WO2006050443A1 (en) * | 2004-11-02 | 2006-05-11 | Rambus Inc. | Pass transistors with minimized capacitive loading |
US7274242B2 (en) * | 2004-11-02 | 2007-09-25 | Rambus Inc. | Pass transistors with minimized capacitive loading |
US20060091932A1 (en) * | 2004-11-02 | 2006-05-04 | Rambus Inc. | Pass transistors with minimized capacitive loading |
US7259589B1 (en) | 2005-09-16 | 2007-08-21 | Pericom Semiconductor Corp. | Visual or multimedia interface bus switch with level-shifted ground and input protection against non-compliant transmission-minimized differential signaling (TMDS) transmitter |
US11088685B2 (en) * | 2017-07-03 | 2021-08-10 | Mitsubishi Electric Corporation | High-frequency switch |
Also Published As
Publication number | Publication date |
---|---|
KR100886011B1 (en) | 2009-02-26 |
US6396325B2 (en) | 2002-05-28 |
JP4230704B2 (en) | 2009-02-25 |
JP2002314388A (en) | 2002-10-25 |
DE10203955A1 (en) | 2002-08-22 |
TW565999B (en) | 2003-12-11 |
KR20020066182A (en) | 2002-08-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6396325B2 (en) | High frequency MOSFET switch | |
KR920004341B1 (en) | Output circuit of integrated circuit | |
US8149042B2 (en) | Analog switch for signal swinging between positive and negative voltages | |
US7463068B2 (en) | Apparatus and method for over-voltage, under-voltage and over-current stress protection for transceiver input and output circuitry | |
EP2478627B1 (en) | An integrated circuit adapted to be selectively ac or dc coupled | |
JP2002314388A5 (en) | ||
EP1585278B1 (en) | Data output circuit with improved overvoltage/surge protection | |
US7449940B2 (en) | Buffer circuit | |
US6483354B1 (en) | PCI-X driver control | |
US20100264970A1 (en) | Edge rate control for i2c bus applications | |
WO2018020783A1 (en) | Ringing suppression circuit | |
EP1728181A2 (en) | High speed transient immune differential level shifting device | |
CN101106373A (en) | Low-voltage differential signal driver for high-speed digital transmission | |
US7336109B2 (en) | High voltage tolerant port driver | |
JP3400294B2 (en) | Pull-up circuit and semiconductor device | |
WO2023030451A1 (en) | Display chip and electronic device | |
US6239619B1 (en) | Method and apparatus for dynamic termination logic of data buses | |
US7474124B2 (en) | Electronic circuit for maintaining and controlling data bus state | |
US20080111580A1 (en) | Suppressing ringing in high speed CMOS output buffers driving transmission line load | |
KR20010062040A (en) | High frequency mos switch | |
US6329834B1 (en) | Reduction of switching noise in integrated circuits | |
US6279145B1 (en) | Apparatus and method for isolating noisy signals in an integrated circuit | |
JPH09321605A (en) | Tri-state buffer | |
EP0766400B1 (en) | Output stage resistant to external overvoltages on its output where powered down in high impedance state | |
US7436215B2 (en) | Transmitter |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FAIRCHILD SEMICONDUCTOR CORPORATION, MAINE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GOODELL, TRENOR F.;REEL/FRAME:011580/0732 Effective date: 20010208 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 12 |
|
AS | Assignment |
Owner name: DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT, NEW YORK Free format text: PATENT SECURITY AGREEMENT;ASSIGNOR:FAIRCHILD SEMICONDUCTOR CORPORATION;REEL/FRAME:040075/0644 Effective date: 20160916 Owner name: DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AG Free format text: PATENT SECURITY AGREEMENT;ASSIGNOR:FAIRCHILD SEMICONDUCTOR CORPORATION;REEL/FRAME:040075/0644 Effective date: 20160916 |
|
AS | Assignment |
Owner name: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, ARIZONA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FAIRCHILD SEMICONDUCTOR CORPORATION;REEL/FRAME:057694/0374 Effective date: 20210722 |
|
AS | Assignment |
Owner name: FAIRCHILD SEMICONDUCTOR CORPORATION, ARIZONA Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:DEUTSCHE BANK AG NEW YORK BRANCH;REEL/FRAME:057969/0206 Effective date: 20211027 |
|
AS | Assignment |
Owner name: DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT, NEW YORK Free format text: SECURITY INTEREST;ASSIGNOR:SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC;REEL/FRAME:058871/0799 Effective date: 20211028 |
|
AS | Assignment |
Owner name: FAIRCHILD SEMICONDUCTOR CORPORATION, ARIZONA Free format text: RELEASE OF SECURITY INTEREST IN PATENTS RECORDED AT REEL 040075, FRAME 0644;ASSIGNOR:DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT;REEL/FRAME:064070/0536 Effective date: 20230622 Owner name: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, ARIZONA Free format text: RELEASE OF SECURITY INTEREST IN PATENTS RECORDED AT REEL 040075, FRAME 0644;ASSIGNOR:DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT;REEL/FRAME:064070/0536 Effective date: 20230622 |
|
AS | Assignment |
Owner name: FAIRCHILD SEMICONDUCTOR CORPORATION, ARIZONA Free format text: RELEASE OF SECURITY INTEREST IN PATENTS RECORDED AT REEL 058871, FRAME 0799;ASSIGNOR:DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT;REEL/FRAME:065653/0001 Effective date: 20230622 Owner name: SEMICONDUCTOR COMPONENTS INDUSTRIES, LLC, ARIZONA Free format text: RELEASE OF SECURITY INTEREST IN PATENTS RECORDED AT REEL 058871, FRAME 0799;ASSIGNOR:DEUTSCHE BANK AG NEW YORK BRANCH, AS COLLATERAL AGENT;REEL/FRAME:065653/0001 Effective date: 20230622 |