Thermal crosstalk

The performance of the temperature controller was measured in the tracking mode. Figure 6.18 shows a graph, where the temperature of one of the three microhotplates is kept at a constant temperature of 300 °C, the temperature of the second microhotplate is modulated using a sine wave of 10 mHz, while rectangular temperature steps of 150 °C, 200 °C, 250 °C, 300 °C, and 350 °C have been appHed to the third microhotplate. Temperature measurements on one of the hotplate that has been operated at constant temperature in the stabihzation mode showed a variation of less than 1 °C, even though the temperature of the neighboring hotplates was, at the same time, modulated dynamically (sine wave, ramp, steps). This is a consequence of the individual hotplate temperature control, without which thermal crosstalk between the hotplates would have been clearly detectable. The power dissipation of the chip is approximately 190 mW, when all three hotplates are simultaneously heated to 350 °C. In the power-down mode, the power consumption is reduced to 8.5 mW. 

Ke et al. showed that a microchip used silicon as substrate eliminating thermal crosstalk with neighboring reaction cavities. The lysis of... 

The low dielectric constant materials improve the density of circuit interconnections in cases where the density is limited by crosstalk considerations rather than by process constraints. Benzocyclobutene is one of the low dielectric constant polymers with excellent electrical, thermal, and adhesion properties. 

As is evident from the data in Table 7.4, alumina is not the most suitable material to fidfill the requirements for an ideal electronic substrate. In particular, its thermal conductivity is among the lowest Hsted, the rather high dielectric permittivity may lead to inductive crosstalk and noise generation as well as signal delay in the... 

The temperature gradient is not to be confused with thermal lag, which is another physical property that should also be minimized in DSC experiments. Thermal lag is the difference between the average sample temperature and the sensor temperature and is caused by so-called thermal resistance, which characterizes the ability of the material to hinder the flow of heat. Thermal lag is smaller in DSC than in DTA because of smaller sample size (milligrams in DSCs), but more types of thermal resistance develop in DSC than in DTA. These effects are caused by introduction of the sample and reference pans into the DSC sample and reference holders. Thus, in DTA thermal resistance develops between the sample holder (in some instruments called the sample pod) and the sample (analogously, between the reference holder and the reference material), and within the sample and the reference materials. On the other hand, in DSC thermal resistance will develop between the sample holder and the bottom of the sample pan and the bottom of the sample pan and the sample (these are called external thermal resistances), and within the sample itself (this is called internal thermal resistance). These thermal resistances should be taken into account since they determine the thermal lag. Let us suppose that the cell is symmetric with regard to the sample and reference pods or holders, the instrumental thermal resistances are identical for the sample and reference holders, the contact between the pans and the pods are intimate, no crosstalk exists between the sample and reference sensors (i.e.. 

Thermal batteries can be designed to provide multiple output voltages by electrically connecting the required number of cells in series. The multiple-voltage outputs can be drawn either from cells that are common to more than one output or from isolated cells whose output is not shared. An electrically isolated group of cells must be used for circuits that cannot tolerate crosstalk from other circuits in a system. It is also possible to combine cell-stack sections with different cell chemistries in the same battery. Such combinations yield the specific performance characteristics of both chemistries from a common unit. An example of this is a battery that combines a cell stack with a chemistry that has a very short... 

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