An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, ...An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio （PSRR） and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD （Bipolar-CMOS-DMOS） technology. The experimental results show that all main expectations are achieved.展开更多
In order to discuss the dormancy characteristics of seeds about Acer miaotaiense Tsoong,an endangered species,the permeability of husk and the effects of inhibitors on seeds germination were tested.The results showed ...In order to discuss the dormancy characteristics of seeds about Acer miaotaiense Tsoong,an endangered species,the permeability of husk and the effects of inhibitors on seeds germination were tested.The results showed that water absorption rate and velocity both increased significantly(P<0.01)when the husk spun off seeds,which meant that seed coat was one of the factors affecting dormancy because the lignification restricted absorption of water from the environment.Some inhibitors existing in the pericarp,seed coat and embryo could inhibit the germination of cabbage seeds.There were obvious differences on the germination rate,radicle length and seedling height(P<0.01),and the inhibition degree was in the order of seed coat>pericarp>embryo.展开更多
文摘An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio （PSRR） and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD （Bipolar-CMOS-DMOS） technology. The experimental results show that all main expectations are achieved.
文摘In order to discuss the dormancy characteristics of seeds about Acer miaotaiense Tsoong,an endangered species,the permeability of husk and the effects of inhibitors on seeds germination were tested.The results showed that water absorption rate and velocity both increased significantly(P<0.01)when the husk spun off seeds,which meant that seed coat was one of the factors affecting dormancy because the lignification restricted absorption of water from the environment.Some inhibitors existing in the pericarp,seed coat and embryo could inhibit the germination of cabbage seeds.There were obvious differences on the germination rate,radicle length and seedling height(P<0.01),and the inhibition degree was in the order of seed coat>pericarp>embryo.
