A novel general-purpose low-voltage rail-to-rail CMOS （ complementary metal-oxide-semiconductor transistor ） operational amplifier （op-amp）is introduced, which obtains constant transconductance, slew rate and cons...A novel general-purpose low-voltage rail-to-rail CMOS （ complementary metal-oxide-semiconductor transistor ） operational amplifier （op-amp）is introduced, which obtains constant transconductance, slew rate and constant high gain over the entire input common mode voltage range. The proposed scheme has the potential for applications in deep submicrometer technology, as the operation of the circuit does not exclusively rely on the square-law or the linear-law of transistors. The scheme is compact and suitable for applications as VLSI cell. The rail-to- rail op-amp has been implemented in DPDM 0. 6 μm mixedsignal process. The simulations show that in the entire range of input common mode voltage, the variations in transconductance, SR and gain are 1%, 2. 3%, 1.36 dB, respectively. Based on this, the layout and tape-out are carded out. The area of layout is 0. 072 mm^2. The test results are basically consistent with the circuit simulation.展开更多
To drive the backplane of a liquid crystal display device and achieve different kinds of grey levels, a high-slew-rate operational amplifier with constant-gin input stage is presented. A Zener-diode structure is inser...To drive the backplane of a liquid crystal display device and achieve different kinds of grey levels, a high-slew-rate operational amplifier with constant-gin input stage is presented. A Zener-diode structure is inserted between the tails of the complementary input pairs to keep the grn of the input stage constant. A novel slew rate enhancement circuit is implemented to achieve a very high slew rate. The chip has been implemented in a 0.5μm CMOS process and the chip area of the operational amplifier circuit is 0.11 mm^2. The testing results indicate that in the 5-8 V input range, the maximum gm fluctuation is only 4.2%. The result exhibits a high slew rate of 111 V/μs and 102 V/μs for the rising and falling edges under a 20 pF capacitance load, and the low frequency gain is up to 109 dB with a phase margin of 70 ℃.展开更多
文摘A novel general-purpose low-voltage rail-to-rail CMOS （ complementary metal-oxide-semiconductor transistor ） operational amplifier （op-amp）is introduced, which obtains constant transconductance, slew rate and constant high gain over the entire input common mode voltage range. The proposed scheme has the potential for applications in deep submicrometer technology, as the operation of the circuit does not exclusively rely on the square-law or the linear-law of transistors. The scheme is compact and suitable for applications as VLSI cell. The rail-to- rail op-amp has been implemented in DPDM 0. 6 μm mixedsignal process. The simulations show that in the entire range of input common mode voltage, the variations in transconductance, SR and gain are 1%, 2. 3%, 1.36 dB, respectively. Based on this, the layout and tape-out are carded out. The area of layout is 0. 072 mm^2. The test results are basically consistent with the circuit simulation.
基金supported by the National Natural Science Foundation of China(No.60876023)
文摘To drive the backplane of a liquid crystal display device and achieve different kinds of grey levels, a high-slew-rate operational amplifier with constant-gin input stage is presented. A Zener-diode structure is inserted between the tails of the complementary input pairs to keep the grn of the input stage constant. A novel slew rate enhancement circuit is implemented to achieve a very high slew rate. The chip has been implemented in a 0.5μm CMOS process and the chip area of the operational amplifier circuit is 0.11 mm^2. The testing results indicate that in the 5-8 V input range, the maximum gm fluctuation is only 4.2%. The result exhibits a high slew rate of 111 V/μs and 102 V/μs for the rising and falling edges under a 20 pF capacitance load, and the low frequency gain is up to 109 dB with a phase margin of 70 ℃.
