Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier
This paper presents a rail-to-rail constant transconductance operational amplifier input stage. The proposed circuit changes the tail current of the input differential pairs dynamically for a constant-gm by using dummy input differential pairs. The problem which causes total gm variation is input pa...
| Main Authors: | , |
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| Format: | Article |
| Language: | zho |
| Published: |
National Computer System Engineering Research Institute of China
2020-01-01
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| Series: | Dianzi Jishu Yingyong |
| Subjects: | |
| Online Access: | http://www.chinaaet.com/article/3000112378 |
| _version_ | 1818066856944074752 |
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| author | Gao Yuhong Li Junlong |
| author_facet | Gao Yuhong Li Junlong |
| author_sort | Gao Yuhong |
| collection | DOAJ |
| description | This paper presents a rail-to-rail constant transconductance operational amplifier input stage. The proposed circuit changes the tail current of the input differential pairs dynamically for a constant-gm by using dummy input differential pairs. The problem which causes total gm variation is input pairs and dummy input pairs can not take effect at the same time with the common-mode input voltage changes, because the tail current transistor of the input pairs are in triode region when the input pairs are turned off, the dummy input pairs will enter subthreshold region from cut-off region before the input pairs when common-mode voltage changes. The effect of this problem is more obviously in low supply voltage design. To solve this problem, compensate current sources is added to the tail current transistors of each dummy input differential pairs for lower gm variation. The gm of this Op Amp′s input stage varies around ±2%. |
| first_indexed | 2024-12-10T15:14:26Z |
| format | Article |
| id | doaj.art-9acbb936c99e4aa48c35302b7da5eafc |
| institution | Directory Open Access Journal |
| issn | 0258-7998 |
| language | zho |
| last_indexed | 2024-12-10T15:14:26Z |
| publishDate | 2020-01-01 |
| publisher | National Computer System Engineering Research Institute of China |
| record_format | Article |
| series | Dianzi Jishu Yingyong |
| spelling | doaj.art-9acbb936c99e4aa48c35302b7da5eafc2022-12-22T01:43:50ZzhoNational Computer System Engineering Research Institute of ChinaDianzi Jishu Yingyong0258-79982020-01-01461485110.16157/j.issn.0258-7998.1910923000112378Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifierGao Yuhong0Li Junlong1Lvliang University，Lvliang 033000，ChinaLvliang University，Lvliang 033000，ChinaThis paper presents a rail-to-rail constant transconductance operational amplifier input stage. The proposed circuit changes the tail current of the input differential pairs dynamically for a constant-gm by using dummy input differential pairs. The problem which causes total gm variation is input pairs and dummy input pairs can not take effect at the same time with the common-mode input voltage changes, because the tail current transistor of the input pairs are in triode region when the input pairs are turned off, the dummy input pairs will enter subthreshold region from cut-off region before the input pairs when common-mode voltage changes. The effect of this problem is more obviously in low supply voltage design. To solve this problem, compensate current sources is added to the tail current transistors of each dummy input differential pairs for lower gm variation. The gm of this Op Amp′s input stage varies around ±2%.http://www.chinaaet.com/article/3000112378rail-to-railoperational amplifiercompensate current |
| spellingShingle | Gao Yuhong Li Junlong Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier Dianzi Jishu Yingyong rail-to-rail operational amplifier compensate current |
| title | Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier |
| title_full | Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier |
| title_fullStr | Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier |
| title_full_unstemmed | Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier |
| title_short | Design of a low-voltage constant transconductance rail-to-rail CMOS operational amplifier |
| title_sort | design of a low voltage constant transconductance rail to rail cmos operational amplifier |
| topic | rail-to-rail operational amplifier compensate current |
| url | http://www.chinaaet.com/article/3000112378 |
| work_keys_str_mv | AT gaoyuhong designofalowvoltageconstanttransconductancerailtorailcmosoperationalamplifier AT lijunlong designofalowvoltageconstanttransconductancerailtorailcmosoperationalamplifier |