Abstract: A liquid metal socket test fixture system and a method for the same are provided. The system has a circuit board top surface and a plurality of wells. A liquid metal compound forms balls in the wells. An IC package having a bottom surface with electrical contacts interfaces with the liquid metal compound in the wells. In some aspects of the system, the IC package has solid ball grid array (BGA) connectors attached to the bottom surface electrical contacts, interfacing with the liquid metal compound. Alternately, the liquid metal compound interfaces directly to the IC package bottom surface contacts. A gravity-tension frame overlies the circuit board top surface. The frame provides support in the horizontal plane so that the liquid metal balls remain aligned with the IC package electrical contacts. Typically, the liquid metal compound is a mixture of approximately 24% indium and 76% gallium.

Abstract: A system and method are provided for reducing the threshold bias offset voltage in a comparator, by canceling and bypassing the bias offset current errors. The comparator system comprises amplification stages with bias cancellation circuitry and a threshold setting circuit. The bias offset current cancellation circuit is used to cancel the base current of differential amplifier input emitter follower. The bias offset current cancellation circuit also cancels the loading effect of amplifier input emitter-follower driving stage. The threshold offset voltage is further reduced by the threshold setting circuit. The threshold-setting circuit includes two integrators and a unit gain operation amplifier. The integrators have the input accept a single-ended input signal, an output connected to the negative input of the comparator, and an output connected to the unit gain operational amplifier, whose output is connected to the negative input of the comparator.

Abstract: A system and method are provided for measuring pseudorandom non-return to zero (NRZ) data rates in a communications device integrated circuit (IC). The system comprises a transition detector to sample a pseudorandom NRZ data stream and to supply a mean frequency of transitions (Fd). A probability analyzer receives the mean frequency of transitions, compares the mean frequency of transitions to a transition probability (P), and supplies a derived mean data stream rate (B), where B=Fd/P. In some aspects of the system, a gating circuit is included to supply a gate time period (Td). Then, the probability analyzer receives the gate time period, compares a mean transition count of the mean frequency of transitions to a transition probability (P), and supplies a compensated transition count (Nc), where Nc=Np/P. A system for selecting the frequency range of a VCO, for use in pseudorandom NRZ communications, is also disclosed.