Abstract: A method of cooling a rocket engine that includes removal of a gaseous propellant from a tank containing liquid propellant, thereby cooling the propellant in the tank, cooling a rocket engine with a coolant, thereby heating the coolant, and transferring heat from the heated coolant into the propellant in the tank, thereby heating the propellant in the tank and maintaining the pressure in the tank. In certain embodiments, the coolant is injected into the rocket engine after transferring heat from the rocket engine to the propellant in the tank.

Abstract: A check valve is disclosed that includes a base having a porous first surface, a keeper coupled to the base, and a flexible leaf with a first section that is fixedly coupled between the keeper and the base and a second section that is cantilevered from the first section. The leaf has a first position when the leaf is fully in contact with the base and a second position when the leaf is fully in contact with the keeper. The leaf is configured to sealingly cover the porous first surface when the leaf is in the first position. The leaf is in an unstressed configuration when in the first position, and a maximum stress in the leaf is less than the yield stress when the leaf is in the second position. The check valve is particularly suited for use with cryogenic fluids such as liquid hydrogen and liquid oxygen.

Abstract: An improved coaxial injector for injecting first and second propellants into a combustion chamber of a rocket engine is provided. The injector includes a first plate, a second plate, a plurality of channels formed in the first plate, and a plurality of tubes extending through the second plate and into the plurality of channels. The tubes inject a first propellant, such as an oxidizer, into the combustion chamber, and the channels inject a second propellant, such as a fuel, around the tubes and into the combustion chamber.

Abstract: A coolant system for a rocket propulsion system having a rocket engine and a propellant tank includes a first heat exchanger that is operatively coupled to the rocket engine. The cooling system also includes a second heat exchanger that is operatively coupled to the propellant tank, a coolant tank that is configured to hold a coolant, and a pump. The cooling system also includes a flow circuit, through which the coolant flows with the aid of the pump. The flow circuit is defined by the pump, the first heat exchanger, the second heat exchanger and the coolant tank. The coolant is pumped by the pump from the coolant tank to the first heat exchanger. The heat of combustion from the rocket engine is transferred to the coolant to cool the rocket engine. The heated coolant transfers the heat therein to the propellant with the second heat exchanger, thereby causing a pressure of the propellant in the propellant tank to be maintained at a desired level.

Abstract: The present invention relates to rocket engine combustion chambers, and more particularly to an improved rocket engine combustion chamber having a jacket. In some embodiments, a combustion system for a rocket engine includes an injector, a cylindrical combustion chamber, and a jacket coupled to the combustion chamber and to the injector. The combustion chamber can expand axially and/or radially with respect to the jacket. The outer surface of the combustion chamber includes a plurality of flow channels. One or more piston seals and/or bellows can be included to allow axial expansion of the combustion chamber with respect to the jacket. A gap formed between the inner surface of the jacket and the outer surface of the combustion chamber allows for radial expansion of the combustion chamber with respect to the jacket.

Abstract: A propulsion system for a rocket engine and a method of cooling a rocket engine includes a propellant tank fluidically coupled to the rocket engine to hold a pressurized propellant, a coolant tank to hold a coolant, a first heat exchanger thermally coupled to the rocket engine and fluidically coupled to the coolant tank, a second heat exchanger thermally coupled to the propellant tank and fluidically coupled to the first heat exchanger, and a third heat exchanger disposed inside the propellant tank to thermally couple a propellant withdrawn from the tank for combustion to a propellant disposed inside the tank. The coolant flows from the coolant tank to the first heat exchanger and through the first heat exchanger to cool the rocket engine. The propellant withdrawn from the propellant tank receives heat from the propellant disposed inside the tank through the third heat exchanger to convert to a gaseous propellant when withdrawn from the propellant tank as a liquid propellant.

Abstract: A system and method of driving a fuel pump and/or an oxidizer pump in a propulsion system includes pumping an oxidizer from an oxidizer supply to a rocket engine with the oxidizer pump. A first portion of the pumped oxidizer is used for combustion in the rocket engine. The heat from the combustion of the first portion of the oxidizer is then transferred to a second portion of the pumped oxidizer to convert the second portion of the oxidizer to a super-heated gaseous oxidizer. The super-heated gaseous oxidizer operates a motor, which drives the oxidizer pump and/or the fuel pump.

Abstract: A propulsion system for a rocket engine and a method of cooling a rocket engine includes a propellant tank fluidically coupled to the rocket engine to hold a pressurized propellant, a coolant tank to hold a coolant, a first heat exchanger thermally coupled to the rocket engine and fluidically coupled to the coolant tank, a second heat exchanger thermally coupled to the propellant tank and fluidically coupled to the first heat exchanger, and a third heat exchanger disposed inside the propellant tank to thermally couple a propellant withdrawn from the tank for combustion to a propellant disposed inside the tank. The coolant flows from the coolant tank to the first heat exchanger and through the first heat exchanger to cool the rocket engine. The propellant withdrawn from the propellant tank receives heat from the propellant disposed inside the tank through the third heat exchanger to convert to a gaseous propellant when withdrawn from the propellant tank as a liquid propellant.

Abstract: A tank for carrying cryogenic fluids and/or hydrogen peroxide and a method of forming the same is provided. A vehicle incorporating such a tank as part of the vehicle structure is also provided. The tank includes an inner wall compatible with the fluid to be carried, an outer wall, and a spacing layer sandwiched between the two walls. In an exemplary embodiment, the outer wall forms part of the structure of a flight vehicle.

Abstract: A method and apparatus for clocking an integrated circuit. The apparatus includes an integrated circuit having a clock driver disposed in a first side of a semiconductor substrate, and a clock distribution network coupled to the clock driver and disposed in a second side of the semiconductor substrate to send a clock signal to clock an area of the integrated circuit.

Abstract: A static random access memory device used in a system having a data clock includes a recirculating counter producing a pair of clocking signals and n data latches each connected to a source of data chunks. Logic receiving a strobe signal, inverse strobe signal, and the clocking signals, successively latches serial data chunks into n data latches, respectively, such that a data chunk is latched one per each cycle of the data clock and so that every n data chunks form a group of parallel data. A delay circuit delaying certain ones of the data chunks latched into the input data latches long enough to permit all data chunks in a group to be transferred in parallel to further memory circuit, wherein the parallel transfer takes place once every n cycles of the data clock.

Abstract: A method and apparatus for clocking an integrated circuit. The apparatus includes an integrated circuit having a clock driver disposed in a first side of a semiconductor substrate, and a clock distribution network coupled to the clock driver and disposed in a second side of the semiconductor substrate to send a clock signal to clock an area of the integrated circuit.

Abstract: A method and an apparatus for performing circuit edits through the back side of a flip-chip packaged integrated circuit die. In one embodiment, a circuit edit is achieved by exposing first and second circuit edit connection targets through a semiconductor substrate of the integrated circuit die from the back side. Next, an insulating layer is deposited over the first and second circuit edit connection targets and the exposed semiconductor substrate. Next, the circuit edit connection targets are re-exposed through the insulating layer and a conductor is deposited over the re-exposed circuit edit connection targets and the deposited insulating layer from the back side of the integrated circuit to couple together the circuit edit connection targets.

Abstract: A method and apparatus for detecting resistive defects in a memory device. A pulldown device is placed at the end of a wordline opposite the end of the wordline having a wordline driver. When the test mode is enabled the wordline pulldown device is turned on. By tailoring the on resistance of the pulldown device such that it is a few times larger than the wordline wire resistance, a resistive divider may be created between the wordline wire resistance and the pulldown device resistance. If a resistive defect exists in the wordline, the increased wordline resistance will create a voltage drop in the wordline when the pulldown device is turned on. This voltage drop indicates that a defect exists in the wordline, and the defect may be located by determining the area of the wordline in which the voltage drop occurs.

Abstract: A method and apparatus for clocking an integrated circuit. The apparatus includes an integrated circuit having a clock driver disposed in a first side of a semiconductor substrate, and a clock distribution network coupled to the clock driver and disposed in a second side of the semiconductor substrate to send a clock signal to clock an area of the integrated circuit.

Abstract: Briefly, in accordance with one embodiment of the invention, an integrated circuit includes: a latching sense amp circuit. The latching sense amp circuit is configured in the integrated circuit so that the signals to produce and latch an output signal consist essentially of a precharge pulse and a capture pulse.

Abstract: A high frequency input buffer within an integrated circuit that is used to receive a signal from another integrated circuit is described. A preamplifier for use in an input buffer of the integrated circuit is described. The preamplifier includes a differential amplifier with differential input terminals and output terminals. An input data signal and an input reference signal are applied to the differential inputs. The differential output signals are generated in response to the differential input signals and are adapted to be applied to the differential input terminals of an amplifier within the input buffer. An adjusting device within the preamplifier adjusts the differential outputs such that they are in a region of optimum gain for the amplifier.

Abstract: A method and an apparatus for performing circuit edits through the back side of a flip-chip packaged integrated circuit die. In one embodiment, a circuit edit is achieved by exposing first and second circuit edit connection targets through a semiconductor substrate of the integrated circuit die from the back side. Next, an insulating layer is deposited over the first and second circuit edit connection targets and the exposed semiconductor substrate. Next, the circuit edit connection targets are re-exposed through the insulating layer and a conductor is deposited over the re-exposed circuit edit connection targets and the deposited insulating layer from the back side of the integrated circuit to couple together the circuit edit connection targets.

Abstract: A method and apparatus to increase the size of the design window for write margin and read stability margin of memory cells without requiring a voltage above the power supply voltage or below ground. An SRAM consisting of an SRAM cell having a ground reference and a circuit coupled to receive a first signal and coupled to drive the ground reference. The circuit is configured to drive the ground reference to a first voltage if the first signal is in a first state. The circuit is configured such that the first node is at a second voltage if the first signal in a second state, the first signal being in the first state indicating a write operation, the first signal being in the second state indicating a non-write operation, the first voltage being greater than the second voltage.

Abstract: A method and apparatus for detecting resistive defects in a memory device. A pulldown device is placed at the end of a wordline opposite the end of the wordline having a wordline driver. When the test mode is enabled the wordline pulldown device is turned on. By tailoring the on resistance of the pulldown device such that it is a few times larger than the wordline wire resistance, a resistive divider may be created between the wordline wire resistance and the pulldown device resistance. If a resistive defect exists in the wordline, the increased wordline resistance will create a voltage drop in the wordline when the pulldown device is turned on. This voltage drop indicates that a defect exists in the wordline, and the defect may be located by determining the area of the wordline in which the voltage drop occurs.