Texas Instruments Corporation

Brian Lum-Shue-Chan

Karthik Kadirvel

Bertan Bakkaloglu

Umar Jameer Lyles

Steve Edward Harrell

Vadim Valerievich Ivanov

John H Carpenter, Jr

John Houldsworth

Gary Lee Stirk

Wallace Edward Matthews

Brian Allen

Embodiments of the systems and methods of direct cell attachment for battery cells disclosed herein operate without the protection FETs and the protection IC, thereby enabling the direct attachment of battery cells to the system without compromising safety. A charger IC comprises a switching regulator whose output is used to charge the battery through a pass device. In example embodiments of the disclosed systems and methods of direct cell attachment, a combination of switching FETs and the pass device are used as a protection device instead of the charge and discharge FETs. During normal operation, the pass device may be used to charge the battery using the traditional battery charging profile. Under fault condition, the switching FETs and pass device may be driven appropriately to protect the system.

Systems and methods of direct cell attachment for batteries

An amplifier having an inverting input and a non-inverting input; a capacitor coupled to inverting input of the amplifier; an input voltage conveyance control circuit, having a first switch and a second switch, the first switch coupled to the capacitor, and the second switch coupled to the non-inverting input of the amplifier; a reference voltage conveyance control circuit having a third switch and a fourth switch, a shared node coupled between third switch and fourth switch, the fourth switch coupled to the non-inverting input of the amplifier; a fifth switch coupled to an output of the amplifier; a leakage control circuit having a sixth switch and seventh switch, the sixth switch coupled between the inverting amplifier input and the fifth switch, the seventh switch coupled to the sixth switch and the capacitor; and a first resistor coupled from the output of the amplifier to the first switch.

Auto-zeroed amplifier with low input leakage

Systems and methods are provided for monitoring a voltage. A level shifter is configured to generate a current proportional to the voltage of the battery cell. A delta-sigma modulator is configured to convert the current into a first density modulated bitstream representing the voltage of the battery cell. A first reference source is configured to provide a second density modulated bitstream representing a first threshold voltage. A first comparator is configured to compare the first density modulated bitstream and the second density modulated bitstream.

Voltage monitoring using bitstream signal processing

Systems and methods for analog to digital conversion charge storage device measurement are presented. In multi-cell charge storage device monitoring systems, accurate measurement of cell voltages is used for protection of the multi-cell device. The disclosed cell referenced solution converts the cell voltage to a digital representation referenced at the cell voltage. The digital representation referenced to the cell voltage is then level shifted to a ground referenced signal suitable for digital post processing. This processing may be used for fault detection of over-voltage, under-voltage, open cell, and similar fault conditions and cell capacity measurements. An example embodiment implements a sigma delta modulator to perform the signal transformation from analog to digital. The disclosed systems and methods may be differential and stackable for multiple cells.

Systems and methods for analog to digital converter charge storage device measurement

Various apparatuses and methods for detecting cell connection status of a multi-cell battery are disclosed herein. For example, some embodiments provide an apparatus for detecting cell connection status of a multi-cell battery. The apparatus includes a battery cell input for each cell, a cell connection status detector for each cell, and at least one comparator. Each of the cell connection status detectors is connected to a battery cell input and has a current-based status indicator output. The at least one comparator is connected to the current-based status indicator outputs. Each of the plurality of cell connection status detectors floats in a different supply voltage range. The at least one comparator is referenced to a lower voltage potential than at least one of the plurality of cell connection status detectors.

Multi-cell power system controller

A relatively low frequency chopping operation is applied to a delta-sigma ADC to reduce DC offsets resulting from non-ideal component operation. Sequential chopping takes place outside a closed loop and may include an inverted polarity feedback for a part of the chopping period. Nested chopping involves chopping within the closed loop, and may include an inverted polarity feedback and a time shift. The feedback compensation for sequential and nested chopping permits the correct polarity feedback to be provided at the desired time in conjunction with sampling and quantization events. Integrating capacitor(s) may be swapped in relative polarity during nested chopping to preserve residual conversion information for the desired polarity. The ADC operation is non-temperature dependent and avoids modification to the useful signal, resulting in higher accuracy.

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Palm Bay, FL, United States of America

Brian Lum-Shue-Chan