In view of the poor tiansient response of the output-capacitorless, an output-capacitorless low dropout (LDO) regulator with fast transient response is proposed, and the voltage overshoot and undershoot suppression circuits are used to suppress voltage jumps, thus improving the transient response characteristics of the LDO regulator. An improved error amplifier is designed, whose gain is larger than that of a general error amplifier in static working states. In addition, the transient output current from the designed error amplifier can be increased when the output voltage jumps, and the charging and discharging of the power tube can be accelerated. By using Current buffer Miller compensation, the phase margin of the circuit is compensated with a smaller capacitive area. Simulation results show that when the voltage range is 2.8~3.3 V, the output voltage from the circuit is 1.8 V and the maximum load current is 50 mA. When the load current jumps between 1 and 50 mA, the undershoot amplitude of output voltage is reduced by 46 mV (51%) and the response time is 1.16 µs under the effect of the transient enhancement circuit. Meanwhile, the overshoot amplitude is reduced by 29 mV (35%), and the response time is 1.18 µs.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |