Abstract: Improved solar cell circuit layouts and cell structures that protect solar arrays located on spacecraft disposed in geosynchronous earth orbit from electrostatic discharge. An insulating material, such as RTV adhesive, for example, is used as a barrier that disposed in intercell gaps between solar cells. The use of the insulating material modifies sparking in the gaps caused by electrostatic discharge so that, while the spark still occurs, it has different non-destructive characteristics. The use of the insulating material causes no damage to other solar cell materials, such as a Kapton insulating layer or substrate used to support the solar cells. Furthermore, unique solar cell wiring schemes are provided that limit the voltage between adjacent solar cells to 50 volts or less.

Abstract: A battery cell bypass module comprises a sensor for detecting an operating condition of a battery cell such as voltage or temperature and a controller connected across the battery cell of a lithium ion battery, for example, and having a conductive mode and a normally non conductive mode. The controller is operable to change to the conductive mode when an operating condition of the battery cell exceeds a predetermined value to thereby shunt current around the battery cell. The sensor may be a temperature transducer such as a thermistor for measuring battery cell temperature and a cell temperature comparator such as an operational amplifier is operable to generate a temperature excessive signal when the signal from the temperature transducer exceeds a predetermined value, the controller then being operable to change to the conductive mode and thereby shunt current around the battery cell.

Abstract: A system for managing the operation of a battery such as a lithium ion battery having a plurality of serially connected individual cells comprises a bypass module electrically in parallel with each individual cell or, alternatively, with at least one of the cells or alternatively again with an individual cell and its associated grouping of one or more parallel cells. The module includes a sensor for detecting an operating condition of its associated cell and a charger operable for charging the cell. A charge controller is electrically connected with each bypass module and is operable in response to an operating condition of a cell detected by the sensor which is outside a predetermined range of magnitudes to change the bypass module to the conductive mode and thereby shunt current around the battery cell, while leaving unaffected each of the remaining cells.

Abstract: An improved digital switching voltage regulator 10 for providing a regulated voltage having a well defined steady state ripple component is disclosed herein. The improved voltage regulator 10 of the present invention includes a control circuit 25 for providing a first output voltage and at least one shift pulse when the voltage across a load 21 operatively coupled to the regulator 10 departs from a voltage regulation window by crossing an upper threshold voltage thereof. The control circuit 25 also provides a second output voltage and at least one shift pulse when the load voltage departs from the voltage regulation window by crossing a lower voltage threshold thereof. A bi-directional shift register 50 generates a set of control voltages in response to the output voltage of the control circuit 40 and the shift pulse. Current is provided to the load 21 by an array 70 of switchable current sources in response to the set of control voltages.

Abstract: A digital switching voltage regulator 10 for providing regulation about a single voltage despite the current supplied thereby is disclosed herein. The digital switching voltage regulator 10 of the present invention includes a first voltage regulation module 12 for regulating, within a first voltage regulation window RW1 defined by first upper and lower threshold voltages, the voltage across a load 21 operatively coupled to the regulator 10. The regulator 10 of the present invention further includes a second voltage regulation module 14 for regulating the voltage across the load 21 within a second voltage regulation window RW2 defined by second upper and lower threshold voltages. The second voltage regulation window 14 is included within the first voltage regulation window 12 and, in a preferred embodiment, the first and second regulation windows RW1 and RW2 are centered about a common voltage.