This paper reports that a 5-cm length birefringent photonic crystal fibre is used to tune the output frequency of unamplified 10-fs Ti：sapphire pulses. The zero dispersion of the fibre is at 823 nm and 800 nm for slo...This paper reports that a 5-cm length birefringent photonic crystal fibre is used to tune the output frequency of unamplified 10-fs Ti：sapphire pulses. The zero dispersion of the fibre is at 823 nm and 800 nm for slow and fast fundamental modes, respectively. It is demonstrated that efficient upshift of the output frequency can be achieved when the pumped radiation is polarized along the slow axis of the fibre. When the average input power reaches 320 mW, about 60% of the output energy is located in one peak at 600 nm and is accompanied by depletion of the pulse inside the anomalous dispersion region.展开更多
An on-chip power-on reset circuit with a brown-out detection capability is implemented in a 0. 18 μm CMOS. A pF-order capacitor is charged with a proportional-to-absolute-temperature （PTAT） current from a bandgap r...An on-chip power-on reset circuit with a brown-out detection capability is implemented in a 0. 18 μm CMOS. A pF-order capacitor is charged with a proportional-to-absolute-temperature （PTAT） current from a bandgap reference with limited loop bandwidth and slow start-up feature, to generate a reset signal with high robustness and wide-range supply rise time. An embedded brown- out detector based on complementary voltage-to-current （V-to-I） conversion and current comparison can accurately respond to the brown-out event with high robustness over process and temperature when the supply is lower than 1.5 V and the brown-out duration is longer than 0. 1 ms. The presented design with embedded offset voltage cancellation consumes a quiescent current of 8. 5 μA from a 1. 8 V supply and works over ambient temperature of -40° to 120°.展开更多
Single event latch-up (SEL) is a significant issue for electronics design in space application, which would cause large currents in electronic devices, and may lead to burning out of devices. A new monitoring circuit ...Single event latch-up (SEL) is a significant issue for electronics design in space application, which would cause large currents in electronic devices, and may lead to burning out of devices. A new monitoring circuit based on current-comparing method is designed to protect the electronics away from SEL’s damage in radiation environment. The response time of protection circuit has been analyzed. The signal simulation results indicated that the operating time of the SEL protection circuit is dependent on the action time of current comparator and system application recovery time. The function of the monitoring circuit protection device away from SEL’s damage has validated through experiment at last.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos 10874145 and 60490280)the China Postdoctoral Science Foundation(Grant No 20080440014)the Yanshan University Doctor Foundation of China(Grant No B153)
文摘This paper reports that a 5-cm length birefringent photonic crystal fibre is used to tune the output frequency of unamplified 10-fs Ti：sapphire pulses. The zero dispersion of the fibre is at 823 nm and 800 nm for slow and fast fundamental modes, respectively. It is demonstrated that efficient upshift of the output frequency can be achieved when the pumped radiation is polarized along the slow axis of the fibre. When the average input power reaches 320 mW, about 60% of the output energy is located in one peak at 600 nm and is accompanied by depletion of the pulse inside the anomalous dispersion region.
基金Supported by the National Natural Science Foundation of China(6130603761201182)
文摘An on-chip power-on reset circuit with a brown-out detection capability is implemented in a 0. 18 μm CMOS. A pF-order capacitor is charged with a proportional-to-absolute-temperature （PTAT） current from a bandgap reference with limited loop bandwidth and slow start-up feature, to generate a reset signal with high robustness and wide-range supply rise time. An embedded brown- out detector based on complementary voltage-to-current （V-to-I） conversion and current comparison can accurately respond to the brown-out event with high robustness over process and temperature when the supply is lower than 1.5 V and the brown-out duration is longer than 0. 1 ms. The presented design with embedded offset voltage cancellation consumes a quiescent current of 8. 5 μA from a 1. 8 V supply and works over ambient temperature of -40° to 120°.
文摘Single event latch-up (SEL) is a significant issue for electronics design in space application, which would cause large currents in electronic devices, and may lead to burning out of devices. A new monitoring circuit based on current-comparing method is designed to protect the electronics away from SEL’s damage in radiation environment. The response time of protection circuit has been analyzed. The signal simulation results indicated that the operating time of the SEL protection circuit is dependent on the action time of current comparator and system application recovery time. The function of the monitoring circuit protection device away from SEL’s damage has validated through experiment at last.
