Now showing items 1-20 of 45

    • 5GHz CMOS all-pass filter-based true time delay cell 

      Aghazadeh, Seyed Rasoul; Martínez García, Herminio; Saberkari, Alireza (2018-12-22)
      Article
      Open Access
      Analog CMOS time-delay cells realized by passive components, e.g., lumped LC delay lines, are inefficient in terms of area for multi-GHz frequencies. All-pass filters considered as active circuits can, therefore, be the ...
    • 5GHz CMOS all–pass filter–based true time delay cell 

      Aghazadeh Dafsari, Seyed Rasoul; Martínez García, Herminio; Saberkari, Alireza (2018-12-22)
      Article
      Open Access
      Analog CMOS time-delay cells realized by passive components, e.g., lumped LC delay lines, are inefficient in terms of area for multi-GHz frequencies. All-pass filters considered as active circuits can, therefore, be the ...
    • Active inductor-based tunable impedance matching network for RF power amplifier application 

      Saberkari, Alireza; Ziabakhsh, Saman; Martínez García, Herminio; Alarcón Cot, Eduardo José (2015-08)
      Article
      Open Access
      This paper presents the use of a new structure of active inductor named cascoded flipped-active inductor (CASFAI) in a T-type high-pass tunable output matching network of a class-E RF power amplifier (RFPA) to control the ...
    • Active inductor–based tunable impedance matching network for RF power amplifier application 

      Saberkari, Alireza; Ziabakhsh, Saman; Martínez García, Herminio; Alarcón Cot, Eduardo José (2016-01)
      Article
      Open Access
    • An efficient CMOS LDO-assisted DC/DC buck regulator 

      Shirmohammadli, V.; Saberkari, Alireza; Martínez García, Herminio; Alarcón Cot, Eduardo José (2016)
      Conference report
      Restricted access - publisher's policy
      In this paper, a new structure based on linear-assisted DC-DC buck converter principle is proposed. Using a segmented LDO regulator instead of the conventional linear one in the hybrid scheme, reduces the difference between ...
    • An efficient CMOS LDO–assisted DC/DC buck regulator 

      Shirmohammadli, V.; Saberkari, Alireza; Martínez García, Herminio; Alarcón Cot, Eduardo José (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Open Access
    • An output-capacitorless FVF-based low-dropout regulator for power management applications 

      Shirmohammadli, V.; Saberkari, Alireza; Martínez García, Herminio; Alarcón Cot, Eduardo José (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Restricted access - publisher's policy
      This paper presents an output-capacitorless low dropout (LDO) regulator based on improved flipped voltage follower power stage for use in power management circuits. A new error amplifier (EA) structure, named as gain-bandwidth ...
    • Analysis and evaluation of using a tuning inductance on the performance of gilbert cell-based CMOS sub-harmonic mixer 

      Saberkari, Alireza; Shokouhi, Shahriar B.; Alarcón Cot, Eduardo José; Baghersalimi, Gholamreza (2012)
      Article
      Restricted access - publisher's policy
      The effect of using a tuning inductance on the performance of a Gilbert cell-based two level transistor CMOS sub-harmonic mixer is investigated. The tuning inductor used between the RF and LO switching stages causes ...
    • CMOS fast transient low-dropout regulator 

      Saberkari, Alireza; Alarcón Cot, Eduardo José; Shokouhi, Shahriar B. (Institute of Electrical and Electronics Engineers (IEEE), 2012)
      Conference report
      Restricted access - publisher's policy
      In this paper a fast transient response CFA-based low-dropout regulator (LDO) is introduced. The circuit is stable for 0-100mA output load current and a 1μF output capacitor without any internal compensation. The CFA ...
    • CMOS RF first-order all-pass filter 

      Aghazadeh, Seyed Rasoul; Martínez García, Herminio; Saberkari, Alireza; Alarcón Cot, Eduardo José (International Centre for Numerical Methods in Engineering (CIMNE), 2018)
      Conference report
      Open Access
      In this paper, a wide-band first-order voltage-mode all-pass filter is presented. Due to a simple structure and appropriate performance of the proposed all-pass filter, this filter achieves a flat group delay of over 60 ...
    • Design and comparison of flipped active inductors with high quality factors 

      Saberkari, Alireza; Ziabakhsh, Soheil; Martínez García, Herminio; Alarcón Cot, Eduardo José (Institution of Electrical Engineers, 2014-05-19)
      Article
      Restricted access - publisher's policy
      A new design based on the flipped-structure for RF active inductors is presented. The conventional flipped-active inductor (FAI) composed of only two transistors is considered as a starting structure. However, it suffers ...
    • Design and implementation of a sliding-mode controller for digital low-dropout/linear regulators 

      Baheri, Javad; Saberkari, Alireza; Khorgami, Omid; Alarcón Cot, Eduardo José (2018-03-20)
      Article
      Open Access
      This paper presents an approach to utilize of sliding-mode (SM) controller in digital low-dropout/linear regulators. Various design aspects, including the extraction of the regulator state-space model and sliding coefficients ...
    • Design of broadband CNFET LNA based on extracted I-V closed-form equation 

      Saberkari, Alireza; Khorgami, Omid; Bagheri, Javad; Madec, Morgan; Hosseini Golgoo, Seyed Mohsen; Alarcón Cot, Eduardo José (2018-03-31)
      Article
      Open Access
      A procedure of extracting a closed-form user-friendly I-V equation for short channel carbon nanotube field-effect transistors (CNFET) in the saturation region is presented by employing a relation between CNFET parameters ...
    • Double-frequency buck converter as a candidate topology for integrated envelope elimination and restoration applications in power supply of RFPAs 

      Saberkari, Alireza; Shirmohammadli, V.; Martínez García, Herminio; Alarcón Cot, Eduardo José (2015-09-17)
      Article
      Open Access
      This paper proposes the use of double-frequency (DF) buck converter architecture consisting of a merged structure of high and low frequency buck cells as a candidate topology for envelope elimination and restoration (EER) ...
    • Double–frequency buck converter as a candidate topology for integrated envelope elimination and restoration applications in power supply of RFPAs 

      Saberkari, Alireza; Shirmohammadli, V.; Martínez García, Herminio; Alarcón Cot, Eduardo José (2016-05)
      Article
      Open Access
    • Double–frequency buck converter as a candidate topology for integrated envelope elimination and restoration applications in power supply of RFPAs 

      Saberkari, Alireza; Shirmohammadli, V.; Martínez García, Herminio; Alarcón Cot, Eduardo José (2016-05)
      Article
      Open Access
      This paper proposes the use of double-frequency (DF) buck converter architecture consisting of a merged structure of high and low frequency buck cells as a candidate topology for envelope elimination and restoration (EER) ...
    • Enhancing the performance of output-capacitorless LDO regulators by pass-transistor segmentation 

      Shirmohammadli, V.; Saberkari, Alireza; Martínez García, Herminio; Alarcón Cot, Eduardo José (Institute of Electrical and Electronics Engineers (IEEE), 2016)
      Conference report
      Restricted access - publisher's policy
      This paper deals with a circuit proposal along with theoretical analysis to provide a solution for enhancing the stability and transient performance of external capacitorless low-dropout regulators (CL-LDOs) by segmenting ...
    • Fast transient current-steering CMOS LDO regulator based on current feedback amplifier 

      Saberkari, Alireza; Alarcón Cot, Eduardo José; Shokouhi, Shahriar B. (2013-03)
      Article
      Restricted access - publisher's policy
      This paper presents a current-steering approach to implement a fast transient response low-dropout regulator (LDO) based on a current feedback amplifier (CFA) topology. The circuit does not require any internal compensation ...
    • Four-quadrant linear-assisted DC/DC voltage regulator 

      Martínez García, Herminio; Saberkari, Alireza (2016-04-23)
      Article
      Open Access
      This Mixed Signal Letter presents a proposal of four-quadrant linear-assisted DC/DC voltage regulator. In this topology, a class-AB linear voltage amplifier assists a four-quadrant switching DC/DC converter in order to ...
    • Four–quadrant linear–assisted DC/DC voltage regulator 

      Martínez García, Herminio; Saberkari, Alireza (2016-07)
      Article
      Open Access
      This Mixed Signal Letter presents a proposal of four-quadrant linear-assisted DC/DC voltage regulator. In this topology, a class-AB linear voltage amplifier assists a four-quadrant switching DC/DC converter in order to ...