0.6-V 1.65-uW second-order Gm-C bandpass filter for multi-frequency bioimpedance analysis based on a bootstrapped bulk-driven voltage buffer
Fecha
2022Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión publicada / Argitaratu den bertsioa
Identificador del proyecto
Impacto
|
10.3390/jlpea12040062
Resumen
A bootstrapping technique used to increase the intrinsic voltage gain of a bulk-driven
MOS transistor is described in this paper. The proposed circuit incorporates a capacitor and a cutoff
transistor to be connected to the gate terminal of a bulk-driven MOS device, thus achieving a quasi-
floating-gate structure. As a result, the contribution of the gate transconductance is cancelled out and
...
[++]
A bootstrapping technique used to increase the intrinsic voltage gain of a bulk-driven
MOS transistor is described in this paper. The proposed circuit incorporates a capacitor and a cutoff
transistor to be connected to the gate terminal of a bulk-driven MOS device, thus achieving a quasi-
floating-gate structure. As a result, the contribution of the gate transconductance is cancelled out and
the voltage gain of the device is correspondingly increased. The technique allows for implementing a
voltage follower with a voltage gain much closer to unity as compared to the conventional bulk-driven
case. This voltage buffer, along with a pseudo-resistor, is used to design a linearized transconduc-
tor. The proposed transconductance cell includes an economic continuous tuning mechanism that
permits programming the effective transconductance in a range sufficiently wide to counteract the
typical variations that process parameters suffer during fabrication. The transconductor has been
used to implement a second-order Gm-C bandpass filter with a relatively high selectivity factor,
suited for multi-frequency bioimpedance analysis in a very low-voltage environment. All the circuits
have been designed in 180 nm CMOS technology to operate with a 0.6-V single-supply voltage.
Simulated results show that the proposed technique allows for increasing the linearity and reduc-
ing the input-referred noise of the bootstrapped bulk-driven MOS transistor, which results in an
improvement of the overall performance of the transconductor. The center frequency of the bandpass
filter designed can be programmed in the frequency range from 6.5 kHz to 37.5 kHz with a power
consumption ranging between 1.34 μW and 2.19 μW. The circuit presents an in-band integrated noise
of 190.5 μVrms and is able to process signals of 110 mVpp with a THD below −40 dB, thus leading to
a dynamic range of 47.4 dB [--]
Materias
Bandpass filter,
Bootstrapping,
Bulk-driven,
Linearized transconductor,
Quasi-floating gate,
Voltage follower
Editor
MDPI
Publicado en
Journal of Low Power Electronics and Applications, 2022, 12, 62
Departamento
Universidad Pública de Navarra. Departamento de Ingeniería Eléctrica, Electrónica y de Comunicación /
Nafarroako Unibertsitate Publikoa. Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza Saila /
Universidad Pública de Navarra/Nafarroako Unibertsitate Publikoa. Institute of Smart Cities - ISC
Versión del editor
Entidades Financiadoras
Work funded by projects RTI2018-095994-B-I00, from MCIN/AEI/10.13039/501100011033, and IB18079, from Junta de Extremadura R&D Plan, and by Fondo Europeo de Desarrollo Regional (FEDER) Una manera de hacer Europa.