Electronics and Microelectronics
- Analog Circuit Design: Although, digital circuit design emerges on analog counterpart, analog circuit design is an indispensable part of electronic circuits. Especially, biomedical applications, military applications, transceivers etc. dictate the usage of the analog circuit components. For example, the figure given below shows the structure of the Zero-IF receiver. The design of the receiver and transmitter circuits play key role in the structure of telecommunication. (Dr. Ersin Alaybeyoğlu)
Moreover, naturally occurring signals are analog. All of these natural signals transmitted to the digital domain with ADCs (analog to digital converter) must be transferred back to analog domain with DACs (digital to analog converter). The design of DAC and ADC with low power consumption, high precision and high speed is challenging. At the same time, mechanical, electrical and optical sensors are indispensable part of our life. Especially, sensors play a critical role in biomedical applications. The signals coming from sensors must be amplified with amplifier, filtered with analog filters and converted to digital domain with ADCs.
- Reconfigurable Electronic Circuit Design: Communication technology stands out as an important part of our lives and has a large share in the prosperity of society and the economy. GSM, GPS, biomedical applications and etc. are the essential part of our daily lives. Many kinds of communication such as Wi-Fi, Bluetooth, Global Positioning Systems and so on require capability of transceivers to these communication standards. Generally, the commercial items must be compatible to the standards listed above. For example, cell phone transceivers must process all GSM, GPS, WCDMA, Wi-Fi (IEEE 802.11a/b/g/n), WiMAX, Bluetooth, ZigBee and Ultra Wideband (UWB) and so on for more convenience. Such a transceiver named as multi standard transceivers can process all standards with single chip. To design multi-standard transceiver, LNA, local oscillators, mixers, filters and such architectures must be reconfigurable. (Dr. Ersin Alaybeyoğlu)
- Digital Circuit Design: The first integrated circuit flip-flop with two transistors is invented by Jack Kilby in 1958 at Texas Instruments. Now, 32Gb flash memory has approximately 8 billion transistors. Day by day, as the size of the transistors become smaller, the speed of the transistor increases. Logic gates, memories, SRAM, DRAM, MRAM microcontrollers, microprocessors are some examples of digital circuit design. The global semiconductor market in May 2017 is $31.9 billion. Integrated circuit plays key role in the commercial items. In the next figure, the first transistor (AT & T Archives) and the first integrated circuit (Texas Instruments) are shown below.
Next figure gives the layout of the Intel i7 microprocessor. (Dr. Ersin Alaybeyoğlu)
Publications:
7) A new implementation of capacitor multiplier with cell-based variable transconductance amplifier, Alaybeyoglu E., IET Circuits, Devices & Systems, accepted. (SCI)
6) A new implementation of the reconfigurable analog baseband low pass filter with cell-based variable transconductance amplifier, Alaybeyoğlu E., Kuntman H., Analog Integrated Circuits and Signal Processing, (2018). (SCI)
5) MOSFET-only filter design automation based on polynomial regression with exemplary circuits, Özenli D., Alaybeyoğlu E., Çiçekoğlu O., Kuntman H., AEU-International Journal of Electronics and Communications, (2018). (SCI)
4) A new frequency agile filter structure employing CDTA for positioning systems and secure communications, Alaybeyoğlu E., Kuntman H., Analog Integrated Circuits and Signal Processing, (2016). (SCI-E)
3) CMOS implementations of VDTA based frequency agile filters for encrypted communications, Alaybeyoğlu E., Kuntman H., Analog Integrated Circuits and Signal Processing, (2016). (SCI-E)
2) A new CMOS ZC-CDTA realization and its filter applications, Alaybeyoğlu E., Kuntman H., Turkish Journal of Electrical Engineering and Computer Sciences, (2016). (SCI-E)
1) Design of positive feedback driven current-mode amplifiers Z-Copy CDBA and CDTA, and filter applications, Alaybeyoğlu E., Güney A., Altun M., Kuntman H., Analog Integrated Circuits and Signal Processing, (2014). (SCI-E)
- Semiconductor Device Reliability: Semiconductor circuit devices are fundemental electronic compenents of technological products (automotive electronics, communication tools, television, etc.) that are indispensable for daily life. Thus, the semiconductor devices have an important role in determining the reliability of the product that constains these devices. The reliability of semiconductor devices needs to be tested as soon as possible in order to predict the problems that may be encountered during the use of the products. For this purpose, accelerated life tests are carried out which allow fast information about the degradation of the devices. These tests are operated under stress conditions more severe than normal use conditions. Accelerated stress factors are implemented as temperature, voltage, current, etc. Degradation mechanisms that can occur during the use of devices are obtained by applying stress to the devices in a short time. Reliability investigation allows the development of existing designs and new device designs. (Res. Asst. Hatice Gül Ugranlı)
Publications:
4) A new approach for VDMOSFETs' gate oxide degradation based on capacitance and subthreshold current measurements under constant electrical stress, Sezgin-Ugranlı H.G., Özçelep Y., IEEE Transactions on Electron Devices, (2018). (SCI)
3) Investigation of VDMOSFET's switching power dissipation changes under constant electrical stress, Sezgin-Ugranlı H.G., Özçelep Y., Microelectronics Journal, (2018). (SCI-E)
2) Modelling of degraded power MOSFET effects on inverter static parameters, Sezgin H.G., Özçelep Y., Materials Today: Proceedings, (2016).
1) Characterization and modeling of power MOSFET switching times variations under constant electrical stress, Sezgin H.G., Özçelep Y., Microelectronics Reliability, (2015). (SCI-E)
