Abstract: A cable driver is disclosed which provides a substantially linear output signal corresponding to an input signal received by the cable driver on a transmission line. The cable driver includes a number of switches coupled by delay elements with cause the switches to operate in a sequential order in response to an input signal. Each of the switches couples an associated current source to an output port, producing a substantially linear output signal on a transmission line connected to the output port. The substantially linearity of the output signal increases the rate at which data may be transmitted over the transmission line, while permitting the rise and fall time of a specified portion of the output signal to be controlled to ensure that electro-magnetic interference is not produced.

Abstract: A system of resistive end termination and transmission line routing is disclosed for matching the impedance of an IC load to that of a signal source and a transmission line. Each integrated circuit has an internal termination resistor designed to match the characteristic impedance of the transmission line and preferably also the impedance of the source. When the source drives multiple IC devices on a printed circuit board, the devices are cascaded in a chain with the internal resistors of all but the last IC device in the chain bypassed by a short circuit underneath the device, so that a continuous transmission line is provided to the last IC device. The last IC in the chain, which does not have a short circuit underneath it, provides the necessary resistive termination by simply connecting the appropriate pin to a common reference in the circuit. The invention is also applicable to differential applications in which first and second complementary signal sources feed each IC device.

Abstract: A three-fluid method of non-mercury liquid intrusion porosimetry. The sample to be tested and a quantity of non-wetting intrusion liquid other than mercury are introduced into a sealable, pressurizable chamber, the sample being above the intrusion liquid. The chamber is sealed and evacuated. An intermediate pressurizing liquid, such as mercury, is introduced into the chamber and pressurized by a primary pressurization fluid, such as alcohol or oil, so as to force the intrusion liquid into the pores of the sample. The volume of intermediate pressurization liquid introduced into the chamber is measured as the pressure is increased incrementally, to find the pore distribution of the sample.