RF and SJT Micropower News and Events


$3M Total in small business SBIR and STTR awards since 2007

3/11/2013
Meet us at GOMAC 2013. We will present on Weds, March 21th at 9:30AM and Thursday at the Poster Session

TECHNICAL ABSTRACT

Radiation Tolerant 32dBm Power Amplifier at the 45 nm Node (Weds 9:30 AM - 9:50 AM)

Silicon metal-semiconductor-field-effect-transistors (MESFETs) have been designed and fabricated on the IBM 45nm SOI technology. The MESFETs have breakdown voltages greater than 25V which augment the less than 1V CMOS technology. Here, measured results from a 900MHz wideband power amplifier with greater than 1W output power are reported.

TECHNICAL ABSTRACT

Integrated MESFET-CMOS Low Dropout Regulators for Radiation Tolerant Applications at the 45nm Node (Thurs 10:30 AM - 12:0 PM)

A LDO with an integrated MESFET was fabricated on a 45nm SOI CMOS process. The approach includes a MESFET in a source follower configuration which enables it to be inherently stable without external compensation. The MESFET solution does not require a charge pump due to its depeletion mode behavior and is able to achieve a dropout voltage of less than 170mV at 1A in only 0.245mm2.

1/27/2013
32 dBm Power Amplifier on 45 nm SOI CMOS

IEEE Microwave Theory and Wireless Component Letters

TECHNICAL ABSTRACT

A silicon metal-semiconductor-field-effect-transistor (MESFET) power amplifier operating at 900 MHz fabricated on a 45 nm silicon-on-insulator CMOS process with no changes to the process flow is presented. The soft breakdown of the MESFET is 20 times that of the MOSFET and allowed a single transistor amplifier based on Class A bias conditions to operate at up to 32 dBm output power with an 8 V drain bias. The amplifier had a peak power added efficiency of 37.6%, gain of 11.1 dB, OIP3 of 39.3 dBm and 1 dB compression point at an output power of 31.6 dBm. The device required only 0.125 mm of active area. Additionally, the depletion mode operation of the MESFET enables a simple input bias approach using an inductor to ground at the gate of the device.

3/15/2012
Meet us at RFIC 2012. We will present on Tuesday, June 19th at 10:30AM

TECHNICAL ABSTRACT

Enhanced voltage silicon metal-semiconductor-field-effect-transistors (MESFETs) have been fabricated on a 45nm SOI CMOS technology with no process changes.  MESFETs scaled to Lg = 184nm were fabricated and show a peak fT of 35GHz, current drive of 112mA/mm and breakdown voltages exceeding 4.5V whereas the nominal CMOS voltage was less than 1V on the same process. The devices were characterized from DC to 40GHz and an industry standard TOM3 model has been developed describing their operation. A board level Class AB power amplifier operating at 433MHz was designed, fabricated and measured to have a peak output power of 17dBm and peak PAE of 42.5%.  The supply voltage of the PA was more than twice the breakdown voltage of corresponding CMOS on the same semiconductor process.  The measured PA results were used to validate the model across different bias and input power level conditions.  

11/30/2011
Meet us at GOMAC 2012. We will present on Weds, March 21th at 9:10AM

TECHNICAL ABSTRACT

Enhanced-voltage silicon-metal-semiconductor field-effect transistors (MESFETs) have been fabricated by using 45-nm SOI CMOS technology with no process changes. The devices have been demonstrated on several runs with low statistical variation. RF characterization demonstrates that the devices will be suitable for microwave applications such as X-band.

12/10/2010
Phase I NASA SBIR Awarded to Develop DC DC Converters

TECHNICAL ABSTRACT

We have developed a novel metal-semiconductor field-effect-transistor (MESFET) technology suitable for extreme environment electronics. The MESFET technology is fully CMOS-compatible and can be integrated alongside conventional MOSFETs with no changes to the process flow. Unlike the MOSFETs however, the MESFETs do not require a fragile metal-oxide-semiconductor (MOS) interface and are extremely robust. With breakdown voltages in the range 10-50V the MESFET operating voltage greatly exceeds that of the accompanying CMOS. The combination of CMOS compatibility with high breakdown voltage allows for integrated DC-to-DC power conversion solutions that would otherwise require discrete components based on laterally diffused metal-oxide-semiconductor (LDMOS) devices. The MESFETs are intrinsically radiation tolerant up to 1 Mrad(Si) and have been demonstrated to work over the temperature range -196C to +150C. The Phase 1 R&D we are proposing will characterize the large signal switching performance of the SOI MESFETs for buck converter applications in extreme environments.

POTENTIAL NASA COMMERCIAL APPLICATIONS

Wide temperature range, radiation hard DC-to-DC buck converters that are compatible with advanced CMOS technologies will be widely applicable to NASA science and exploration missions scheduled for the next decade and beyond. The high radiation tolerance we have demonstrated is attractive for orbital earth science studies as well as lunar and interplanetary missions. Our technology may even be suitable for spacecraft that are exposed to high space radiation environments such as the Europa Jupiter System Mission that might accumulate a TID of 1-3 Mrad over a 10 year mission lifetime. Missions to the outer reaches of the solar system often make use of a radiothermal generator (RTG). The power management components of these systems are therefore exposed to on-board radiation from the RTG and require the high level of radiation tolerance we expect from the MESFET technology. The wide temperature operating range will be useful for robotic systems on the Moon or Mars. The current Martian rovers use a thermally controlled warm-electronics-box (WEB) to ensure critical electronic components are not exposed to the full thermal variation of the external environment. Our wide temperature range MESFET technology will allow more circuits to be placed outside the WEB, enabling missions to hostile and extreme environments.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS

With expected annual worldwide sales of $6.6B in 2010, switching converters represent 26% of the global semiconductor market for power conditioning analog components. Switching regulators are also one of the fastest growing segments in the power conditioning IC market with compounded annual growth rates of 17% projected for the period 2007-2012. The growth in linear regulator sales is driven largely by portable consumer electronics including cell phones, PDAs, laptop and tablet computers, and a variety of other portable devices that require high performance power management. As the supply voltage of microprocessors continues to decrease to 1.5V and below the need for low voltage DC-to-DC converters increases. Especially important are high efficiency, low voltage devices proposed here to maintain battery lifetime. SJT Micropower is partnering with Honeywell and working closely with On Semiconductor and others to develop Non-NASA revenue streams.

TECHNOLOGY TAXONOMY MAPPING

(NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.)

Circuits (including ICs; for specific applications, see e.g., Communications, Networking & Signal Transport; Control & Monitoring, Sensors)

Distribution/Management

Microfabrication (and smaller; see also Electronics; Mechanical Systems; Photonics

 

10/16/2010
Phase II NASA SBIR Awarded to Develop Radiation Hard LDO regulators

TECHNICAL ABSTRACT

We have developed a low dropout (LDO) regulator using a patented MESFET transistor technology that can be manufactured in commercial CMOS foundries with no changes to the process flow. The regulator is stable under all load conditions without an external compensation capacitor, thereby reducing the mass/volume of the power management system and increasing reliability. The MESFET-based LDO component has very competitive figures of merit (dropout voltage, transient response, power supply rejection) compared to existing components. During Phase 1 we confirmed that the components were unconditionally stable without an external compensation capacitor over the temperature range -196C to +150C and for radiation doses up to 1 Mrad(Si). We shall build on the Phase 1 design effort to demonstrate two fully integrated LDO regulators rated up to 1A with dropout voltages of less than 50 mV. One part will be fabricated using a qualified rad-hard SOI CMOS foundry in collaboration with Honeywell, one of our commercialization partners. The other component will be fabricated using the low-cost/high-volume foundry available from IBM. Both parts will have a nominal output voltage of 1.8V with 1% accuracy. Other designs will target user adjustable voltages in the range 1.2-2V. The feasibility of using the MESFET technology for low voltage applications (e.g. 0.8V) will be explored. All parts will be tested over the temperature range -150C to +150C and after irradiation exposure to a TID of 1 Mrad from a Co-60 source. The enhanced low dose rate sensitivity (ELDRS) of the components will be studied using a low dose rate Cs-137 source. The characteristics of all the components will be documented, and parts made available to NASA and potential customers as deliverables from the Phase 2 activity. We shall work with our commercialization partners to have the LDO regulator design adopted as a licensed 'IP block' and to develop low cost versions for the wider consumer electronics market.

POTENTIAL NASA COMMERCIAL APPLICATIONS

The MESFET-based linear regulator technology has the potential for widespread NASA applications in power management systems exposed to extreme environments. The high radiation tolerance we have demonstrated is attractive for orbital earth science studies as well as lunar and interplanetary missions. Our technology may even be suitable for spacecraft exposed to high radiation environments such as the Europa Jupiter System Mission. Missions to the outer reaches of the solar system that depend on a radiothermal generator are exposed to on-board radiation from the RTG and require the high level of radiation tolerance we expect from the final MESFET regulator component.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS

Low dropout regulators are ubiquitous in commercial consumer electronics and automotive systems. A non-hardened version of the regulator we are proposing to develop will be inexpensive to manufacture using high volume commercial CMOS foundries. Our business models show that such a component can be manufactured at a cost per die that is competitive with existing products but without the need for an external compensation capacitor thereby reducing the overall costs and part count of the power management system. If this is confirmed our regulator component has the potential for widespread commercial adoption. We are working with our commercialization partners at On Semiconductor and Honeywell to develop these non-NASA applications. As well as a standalone product, we are developing the low dropout linear regulator as a scalable design that can be included in application specific integrated circuits (ASICs) as a licensed 'IP block'. ASICs are widely used for non-NASA applications by the Department of Defense and aerospace companies.

TECHNOLOGY TAXONOMY MAPPING (NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.)

Power Management and Distribution

Radiation-Hard/Resistant Electronics

 

10/1/2010
SJT Micropower Selected to Participate in NIH Commercialization Assistance Program (CAP)

SJT Micropower was selected to participate in the NIH CAP program to help commercialize their wireless Medical Transceiver Technology.

 

4/14/2010
DARPA Phase II STTR Awarded

Fabless Design House SJT Micropower was Awarded a Phase II contract to Develop SiMESFET Low Dropout Regulators and RF Power Amplifiers

 

11/23/2009
NASA Phase I SBIR Awarded

Fabless Design House SJT Micropower was awarded a Phase I SBIR contract from NASA

TECHNICAL ABSTRACT

We have developed a fully integrated LDO regulator using a patented transistor technology that can be manufactured in high volume commercial semiconductor foundries with no changes to the process flow. The regulator is stable under all load conditions without the need for an external compensation capacitor thereby reducing the mass/volume of the power management system and increasing reliability. The existing LDO component has very competitive figures of merit (dropout voltage, transient response, power supply rejection) compared to existing components targeting commercial consumer electronics. The work we are proposing for this Phase 1 activity will confirm the expected wide temperature range operation (-180C to +150C) and radiation tolerance (200krads(Si) to 1 Mrad(Si)) of the existing component. Based on these measurements we shall design, simulate and layout LDO regulators for nominal load currents of 100 mA and 1A for fabrication at two rad-hard CMOS foundries during a follow-on Phase 2 activity. The LDO regulators will be designed as drop-in replacements for many existing components. They can also be integrated directly on chip as part of an application specific integrated circuit thereby reducing the chip count still further.

POTENTIAL NASA COMMERCIAL APPLICATIONS

Radiation tolerant low dropout regulators capable of operating in extreme environments with fewer external components will be of widespread use to NASA missions that target the moon, Mars and Europa. The LDO regulator is a key component in most power management systems including point-of-load supplies. By developing power management components for wide temperature range operation (-180C to +150C) we are enabling missions that will benefit from components mounted directly in the Lunar and Martian environments i.e. outside of any thermally controlled warm box. These components will also be of use in missions to Venus that employ environmental chambers with temperatures controlled to < 150C. The transistor technology we have developed shows very promising high frequency performance and therefore has potential NASA applications beyond power management. These include power amplifiers for X-band (5-10GHz) as well as for ultra-low power data telemetry from medical implants that target the Medical Implant Communications Service (MICS) at 403-405 MHz for monitoring astronaut health. Our metal-semiconductor-field-effect-transistor (MESFET) technology is capable of high voltage operation >>10V. NASA faces challenges with component obsolescence due to the reduction in supply voltage of application specific integrated circuits (ASICs) with each new CMOS generation. Our MESFET component has the potential for extending the life of an ASIC product without the expense of a complete re-design.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS

Low dropout regulators are ubiquitous in commercial consumer electronics and automotive systems. A non-hardened version of the regulator we are proposing to develop will be inexpensive to manufacture using high volume commercial CMOS foundries. Our business models suggest that such a component can be manufactured at a cost per die that is competitive with existing products but without the need for an external compensation capacitor thereby reducing the overall costs and part count of the power management system. If this is confirmed our regulator component has the potential for widespread commercial adoption. Other non-NASA commercial applications of our patented transistor technology include low power transceivers for medical implants that use the FCC approved MICS band as well as for data telemetry within the Industrial, Scientific & Medical (ISM) bands. Our MESFET technology is capable of higher voltage operation than the CMOS transistors making it very suitable as the input/output device in commercial ASICs such as those offered by Honeywell and our other Phase 3 commercialization partners.

 

5/01/2009
NIH Phase II SBIR Awarded

SJT Micropower was awarded a Phase II SBIR contract from NIH to develop a wireless MICS / MedRadio Transceiver

DESCRIPTION:

This proposal describes the research required to design, simulate and manufacture ultra-low power circuitries to be used in a complete transceiver implanted inside the human body. Currently, it is difficult to communicate with devices implanted within the human body and the present commercial technologies do not adequately fill this need. We have identified that circuits using SJT Micropower proprietary MESFET technologies will have a lower current draw resulting in longer lifetimes than conventional devices and will be more suited for implanted devices. In order to improve communication with implanted devices, the FCC implemented the Medical Implant Communications Service (MICS) which is an ultra-low power, unlicensed, mobile radio service for transmitting data in support of diagnostic or therapeutic functions associated with implanted medical devices [1]. The FCC rules require that devices operating in the MICS frequency band of 402-405 MHz are limited to a bandwidth of 300kHz and maximum effective isotropic radiated power (EIRP) of 25 microwatts [1]. During Phase 1 research, we have demonstrated a novel MESFET based output stage and an industry leading phase locked loop frequency synthesizer operating between 402-405MHz. These circuits utilize our patented MESFET transistors, operate with less than 2mA and are the backbone circuitry of a transmitter. SJT Micropower will microfabricate the transmitter circuits from Phase 1 along with additional circuitries for a complete transceiver design during Phase 2. The following Phase 2 objectives will lead to a complete transceiver prototype: Objective 1) Finalize Output Transmitter Section - Frequency Synthesizer and Buffer from Phase 1 Objective 2) Design and Fabricate Input Receiver Stage - LNA Front End Objective 3) Design and Fabricate Backend Receiver Circuitry Objective 4) Integrate all Transceiver Circuitries and Build Final Prototype This device will be implanted within the human body and will improve patients' quality of life. Our technology advantages include the ability to operate with high voltage swings which will decrease the current draw of the output buffer, the ability to provide easier bias circuitry which will reduce component count, the ability to match the impedance of the transceiver antenna without additional matching circuitry and a possibility for lower noise circuitry than conventional MOSFETs. These all result in lower current draw from an implanted battery during data transmission and directly increase the useful lifetime of both the battery and implanted transceiver. In addition, our technology is fabricated on radiation hard SOI processes and does not suffer from ionizing radiation effects which can cripple medical circuitry that must last for many years. We have obtained strong support from microfabrication foundries, design consultants, medical device manufacturers and end users. PUBLIC HEALTH RELEVANCE: Currently, it is difficult for medical devices implanted within the human body to communicate with medical professionals in the outside world. This research will utilize the Medical Implant Communications Service (MICS) to build a novel low power transceiver which will allow physicians the ability to use wireless technology to diagnose and treat their patients. The final devices will permit faster data transfer rates between medical implants and external monitoring/control equipment, consume less power than existing solutions therefore requiring fewer replacement procedures, allow for less patient trauma, have a lower cost per survival day, reduce the risk of infection to patients, enhance the comfort of patients, and expand the freedom of movement of medical personnel working with the equipment [2].

PUBLIC HEALTH RELEVANCE:

Currently, it is difficult for medical devices implanted within the human body to communicate with medical professionals in the outside world. This research will utilize the Medical Implant Communications Service (MICS) to build a novel low power transceiver which will allow physicians the ability to use wireless technology to diagnose and treat their patients. The final devices will permit faster data transfer rates between medical implants and external monitoring/control equipment, consume less power than existing solutions therefore requiring fewer replacement procedures, allow for less patient trauma, have a lower cost per survival day, reduce the risk of infection to patients, enhance the comfort of patients, and expand the freedom of movement of medical personnel working with the equipment [2].

 

10/07/2008
SJT Micropower unveils new Low Dropout Regulator MESFET Application

SJT Micropower, Fountail Hills AZ

Dr. Seth Wilk, of SJT Micropower, Fountain Hills, Arizona presented at this weeks International Telecommunications Energy Conference (Intelec) held in San Diego, CA.. The presentation detailed technical developments of SJT Micropower as they apply to power management and specifically the area of low drop out regulators. By exploiting the depletion mode behavior of an n-channel Si-FET, Dr. Wilk showed several simulations of the device’s extremely low drop-out voltage. Also apparent during the live demonstration was the impressive power supply rejection intrinsic to the technology.

For information on this application contact SJT Micropower or visit our website at www.sjtmicropower.com.

About SJT Micropower - SJT Micropower is a spin-out company commercializing intellectual property developed at Arizona State University. The company offers IP blocks using Si-FET technology based on patented Schottky Junction Transistor design. Founded by Dr.Trevor Thornton, the Director of The Solid State Research Center at ASU, the company has found many applications for its technology including Power Management, RF Transceivers and Medical Implant Devices.

 

9/17/2008
SJT Micropower Presents at IEEE Intelec 2008

SJT Micropower presented new LDO circuitries based on silicon MESFETs at INTELEC 2008 in San Diego; paper entitled "Si-FET Technologies for High Efficiency Boost Converters and Low Drop Out Regulators."

 

9/12/2007
DARPA Phase I STTR Awarded

Fabless Design House SJT Micropower was awarded a Phase I STTR contract to develop low dropout regulators and RF power components using their Si-MESFET technology

Title: SOI MESFETs for Ultra-Low Power Electronic Circuits

Abstract:   Simulations of high performance silicon-on-insulator (SOI) MESFETs show that they can be used for ultra-low power (ULP) radio frequency electronics with high efficiencies. The high efficiency comes from the enhanced voltage swing that the MESFETs can tolerate (5-50V) compared to current VLSI CMOS technologies (1-5V). The SOI MESFETs can be fabricated economically using existing SOI CMOS foundries with no changes to the CMOS process flow. This means the SOI MESFETs can be integrated with state-of-the-art CMOS for ULP mixed signal circuit applications, something that is impossible with GaAs based devices. We propose to design an SOI MESFET based Class E amplifier for ULP communications applications in the Industrial-Scientific-Medical band of frequencies. The MESFET based designs will be compared to equivalent CMOS circuits to quantify the anticipated improvement in the PAE of the MESFET circuits. A hardware demonstrator of the Class E amplifier will be designed and tested using existing SOI MESFETs from a previous SBIR contract. Other examples of ULP circuits in which inductive loads lead to device voltages that would cause failure in traditional CMOS will be explored in any Phase II activity.