0.5 V Multiple-Input Multiple-Output Differential Difference Transconductance Amplifier and Its Applications to Shadow Filter and Oscillator

Abstract

This paper presents new applications of low-voltage and low-power multiple-input multipleoutput differential difference transconductance amplifier (DDTA). The multiple-input bulk-driven MOS transistor (MIBD MOST) technique provides multiple-input of the active device that simplifies the application's topology and reduces its power consumption. The proposed DDTA has been used to realize multiple-input single-output shadow filter. Both voltage-and transimpedance-mode filtering functions can be obtained. The natural frequency and the quality factor of the shadow filter can be independently and electronically controlled using DDTA-based amplifiers. The proposed shadow filter has been modified to work as a shadow oscillator. The condition and frequency of oscillation can be controlled independently and electronically. The DDTA is capable to work with 0.5V supply voltage and consumes 218.2 nW. The applications have been designed and simulated in Cadence using 0.18µm TSMC CMOS technology.INDEX TERMS differential difference transconductance amplifier (DDTA), shadow filter, shadow oscillator, analog filter, low-voltage, low-power CMOS

Current-Mode Shadow Filter with Single-Input Multiple-Output Using Current-Controlled Current Conveyors with Controlled Current Gain

“…The proposed current-mode shadow filters were compared with previous shadow filters in Table 1 . The voltage-mode shadow filters in [ 15 , 22 ], the current-mode shadow filters in [ 27 , 28 , 30 ], and the multi-mode shadow filters in [ 34 ] were selected for comparison. Compared with [ 22 , 27 , 28 ], the proposed filter can provide five filtering functions of LP, HP, BP, BS, and AP filters.…”

“…Many shadow filters (also known as frequency-agile filters) have been introduced [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. These filters can be used for various radio applications and sensor networks including environmental monitoring, vital signs monitoring, and military applications.…”

“…These filters can be used for various radio applications and sensor networks including environmental monitoring, vital signs monitoring, and military applications. Considering the operating mode of these filters, they can be divided into three operating modes: voltage-mode [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ], current-mode [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ], and mixed-mode (or multi-mode) [ 32 , 33 , 34 ].…”

“…Considering the active devices used to realize the voltage-mode shadow filters in [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ], the circuit in [ 10 ] uses operational transresistance amplifiers (OTRA), the circuits in [ 11 , 12 , 13 ] use current-feedback operational amplifiers (CFOA), the circuits in [ 14 , 16 , 17 , 18 ] use voltage differencing transconductance amplifiers (VDTA), the circuit in [ 15 ] uses voltage differencing differential difference amplifiers (VDDDA), the circuit in [ 19 ] uses voltage differencing gain amplifiers (VDGA), while the circuit in [ 21 ] uses operational transconductance amplifiers (OTA), and the circuits in [ 22 ] use differential difference transconductance amplifiers (DDTA). The shadow filters in [ 15 , 16 , 17 , 18 , 19 , 21 , 22 ] offer an electronic tuning capability, but only the filter in [ 15 ] offers five filtering functions, namely low-pass (LP), high-pass (HP), band-pass (BP), band-stop (BS), and all-pass (AP). However, the voltage-mode filter in [ 15 ] does not provide low-output impedance, which is required for voltage-mode circuits.…”

0.5-V 281-nW Versatile Mixed-Mode Filter Using Multiple-Input/Output Differential Difference Transconductance Amplifiers

“…Filters for such applications are in high demand, especially for biosignal and sensor signal processing. Many filters based on multiple-input DDTA have been presented [61][62][63][64][65][66][67][68]. This paper presents a versatile mixed-mode filter using MIMO-DDTAs.…”