The design and comparison of elliptic filters with an OTA-C structure

Kim, D.Y.; Choi, Seok Woo; Ahn, J.C.; Fujii, Nobuo

doi:10.1109/mwscas.1990.140761

Cited by 5 publications

(6 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The error amplifier of the LDO regulator, in the negative feedback condition, constantly compares the error signal with the reference voltage and hence maintaining the constant output voltage by varying the gate to source voltage of the pass transistor accordingly. Since the output of error amplifier is used to drive the gate of the pass transistor which is naturally a capacitive load, the best option for the error amplifier would be an operational transconductance amplifier (OTA) [6,7] with high output impedance (Fig. 2).…”

Section: Introductionmentioning

confidence: 99%

The use of output-capacitorless class-AB CMOS low-dropout regulator for power management

García

2017

2017 IEEE 15th International Conference on Industrial Informatics (INDIN)

View full text Add to dashboard Cite

This article presents the design of a 4.5-V, 450-mA low drop-out (LDO) voltage linear regulator based on a two-stage cascoded operational transconductance amplifier (OTA) as error amplifier. The aforementioned two-stage OTA is designed with cascoded current mirroring technique to boost up the output impedance. The proposed OTA has a DC gain of 101 dB under no load condition. The designed reference voltage included in the LDO regulator is provided by a band gap reference with the temperature coefficient (T ) of 0.025 mV/ºC. The proposed LDO regulator has a maximum drop-out voltage of 0.5 V @ 450 mA of load current, and has the worst case power supply rejection ratio (PSRR) of [54.5 dB, 34.3 dB] @ [100 Hz, 10 kHz] in full load condition. All the proposed circuits are designed using a 0.35 μm CMOS technology. The design is checked in order to corroborate its performance for wide range of input voltage, founding that the circuit design works fine meeting all the initial specification requirements. Keywords-Low drop-out (LDO) voltage linear regulator; operational transconductance amplifier (OTA); band gap reference; cascoded current mirrorI.

show abstract

Section: Introductionmentioning

confidence: 99%

The use of output-capacitorless class-AB CMOS low-dropout regulator for power management

García

2017

2017 IEEE 15th International Conference on Industrial Informatics (INDIN)

View full text Add to dashboard Cite

show abstract

“…DESIGN OF THE OPERATIONAL TRANSCONDUCTANCE AMPLIFIER (OTA) Fig. 3 shows the classical two-stage OTA in CMOS technology [7], where it is operated in +V dd and -V ss power supplies and with an external bias current I bias and having a single ended output. The first stage is the normal n-channel differential input pair (m 1 and m 2 ) with p-channel current mirror as its active load (m 3 and m 4 ).…”

Section: Introductionmentioning

confidence: 99%

Cascoded OTA based low dropout (LDO) voltage regulator

García

2014

Proceedings of the 2014 IEEE Emerging Technology and Factory Automation (ETFA)

View full text Add to dashboard Cite

This article aims to present the design of a 4.5-V, 450-mA low drop-out (LDO) voltage linear regulator based on a twostage cascoded operational transconductance amplifier (OTA) as error amplifier. The aforementioned two-stage OTA is designed with cascoded current mirroring technique to boost up the output impedance. The proposed OTA has a DC gain of 101 dB under no load condition. The designed reference voltage included in the LDO regulator is provided by a band gap reference with the temperature coefficient (T γ ) of 0.025 mV/ºC. The proposed LDO regulator has a maximum drop-out voltage of 0.5 V @ 450 mA of load current, and has the worst case power supply rejection ratio (PSRR) of [54.5 dB, 34.3 dB] @ [100 Hz, 10 kHz] in full load condition. All the proposed circuits are designed using a 0.35 µm CMOS technology. The design is checked in order to corroborate its performance for wide range of input voltage, founding that the circuit design works fine meeting all the initial specification requirements. Keywords-Low drop-out (LDO) voltage linear regulator; operational transconductance amplifier (OTA); band gap reference; cascoded current mirror.

show abstract

“…Hence the unity gain bandwidth is varied by varying the load capacitance to obtain the suitable phase margin (PM) according to the application and hence assuring the stability of the system. In the proposed design (m 4,5 ) and (m 13,12 ), (m 3,6 ) and (m 11,14 ), (m 15,16 ) and (m 7,8 ) form the cascoded pairs with current mirroring. The main design criterion of the proposed OTA is same as the classical OTA design which depends on the Equations (3), (4), and (6).…”

Section: Introductionmentioning

confidence: 99%