Turn-on time

Despite poor MOS channel mobility and high pinch-off resistance, this device demonstrated breakdown voltage of 4,580V and specific on-resistance of 387 mDcm which is only 4% of the theoretical limit of Si for such voltage range. It has also demonstrated excellent dynamic characteristics, showing almost no dependence of turnoff and turn-on times on injected current [41]. 

Now, suppose we had ramped up the gate voltage at a rate of 1 V per second as before, but ramped down faster, say, at the rate of 2 V per second. Then the turn-on time and the turn-off transition times would be different. So in that case we need to split up the crossover... 

Vainshtein et al [5] and Dmitriev et al [6] described the first SiC dynistor diode. This diode is an n-p-n-p thyristor-like structure but without gate contacts. For this device, an n-p+-n+ structure was epitaxially grown on a p+ 6H-SiC substrate using container-free liquid phase epitaxy in a continuous epitaxial process. The contacts were made from Al. The turn-on time constant varied from 1 ns to 10 ns. The recovery time varied from 150 to 200 ns. The static switching voltage varied between 10 V and 50 V with an inverse voltage of up to 90 V. Recently, Edmond et al [7] have fabricated the first a-SiC thyristor which operated up to 350 °C. 

The definitions for turn-on time varied between different labs, but it is basically the time before light emission is detected, ca. 1 Cdm . ... 

Thermal fluctuations probably would have the same effect on real cells. As with the rigid boundary cell, we are using three volts but the weak anchoring reduces the critical voltage considerably. Notice that turn-on time is faster but turn-off is much slower than with the rigid-boundary cell because of the... 

Here, z is the position of the molecule at time t. Rearranging and then integrating gives us the relationship between the nth turn-off time, and the nth turn-on time, toa,n,... 

FIG. 2. Turn on time constant for a = 0° the straight line for Ton is least-squares fitted and determines the curve for Ton. 

Performance measures in supply chain management can include return on assets employed, stock turn, on time delivery, transportation costs and other costs and measures as explained in Chapter 19. 

The turn-on time of presently available liquid crystals operating in the dynamic scattering mode is relatively long. According to Kochlman and Felici [101] the turn-on time of a nematic layer is given by the expression... 

Figure 41. Turn-on time of the dynamic scattering mode versus voltage U with the layer thickness d as parameter dj = 6pm, = 12pm, dj = 25 pm (after reference [69]).

Since the diode turn-on voltage Vt (0.3-0.7 V) is one order less than the power-supply level Vdd (>10 V), the two diodes should have very short turn-on time per cycle. Thereby, it is reasonable to ignore the higher order harmonics of Vc2 (voltage on the resonant capacitor C2), and the amplitude of Vc2 is approximately Vdd + T Assuming Vc2 with zero-phase, the relative phase information of Vmd C2. and /l2 is illustrated in Fig. 26. 

P. Wild and J. Nehring, Turn-on Time Reduction and Contrast Enhancement in Matrix-addressed Liquid Crystal Valves, Appl. Phys. Lett., Vol. 19, p. 335 (1971) and C. Stein and R. Kashnow, A Two-Frequency Coincidence Addressing Scheme for Nematic-Liquid-Crystal Display, Appl. Phys. Lett., Vol. 19, p. 343 (1971). 

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