A new universal biquad filter using differential difference amplifiers and its practical realization

The main connection circuits of the radiation-hardened differential difference amplifier based on the bipolar and field effect technological process

“…The synthesis of modern devices of frequency discrimination is significantly simplified with DDA [4] in a number of cases. The component elements of the active filters on some DDA [3][4][5][6][7][8][9][10][11] are of great practical interest as such circuits are more high-frequency at the identical power consumption [4].…”

New resistorless tunable voltage-mode universal filter using single VDIBA

“…[1]. Recently, several active building block (ABB)based minimal configuration voltage-mode (VM) multiinput single-output (MISO) universal filter structures have been reported in the literature in which for specific connection both capacitors are used as input terminal [2]- [13]. Unfortunately, the internal structures of ABBs in all of above reported filters suffer from the excessive number of transistors and the complexity of the used ABBs, which results in high silicon area in case of onchip fabrication.…”

“…Unfortunately, the internal structures of ABBs in all of above reported filters suffer from the excessive number of transistors and the complexity of the used ABBs, which results in high silicon area in case of onchip fabrication. This can be also seen from Table 1, which summarizes the advantages and disadvantages of previously reported VM MISO filters in [2]- [13] based on various relevant criteria. Full nomenclature of referred ABBs is given in Appendix.…”

“…In this letter we propose a new VM MISO universal filter using the just mentioned VDIBA as active element. The proposed filter structure is an alternative realization to recently published CMOS-RC VM MISO universal filter [17] and compared with other ABB-based counterparts in the literature [2]- [13] and CMOS-RC [17], it shows the following advantages:…”

“…lowpass filter (LP), band-pass (BP), high-pass (HP), band-reject (BR), and all-pass (AP) without the need of additional inverting voltage inputs, which lead to higher complexity of these solutions, (ii) proposed filter is resistorless i.e. no external resistor is needed, a useful feature that cannot be found in [2], [4], [6]- [11], [13], and [17], (iii) it employs only few transistors in total, hence the total transistor area is much smaller than [2]- [13] and [17], (iv) no passive element or ABB parameter matching is required in the design, which is not available in [3], [6]- [9], and [11], (v) suitable for low-voltage operation, while circuits [2]- [13] and [17] are supplied with ±1.3 V or higher DC voltages.…”