1 Introduction

The BQ76952 family of battery monitors supports battery pack configurations with up to 16-series cells. The production data sheet for this family specifies an absolute maximum voltage limit of 85 V on select high voltage pins, with a recommended maximum voltage level of 80 V. A stack of 16 lithium-ion cells with maximum voltage of, for example, 4.2 V, would result in a top-of-stack voltage of 67.2 V.

The device also incorporates high-side NFET drivers with an integrated charge pump, which has a programmable typical voltage of 5.7 V or 11 V, and a maximum level of 7 V or 13 V, respectively. This means with a fully charged battery pack and NFET drivers enabled, the voltage on the driver pins can reach a maximum level of 67.2 V + 7 V = 74.2 V or 67.2 V + 13 = 80.2 V during operation.

However, in some systems the top-of-stack voltage may experience transients due to dynamic charge or discharge events, which may result in brief voltages exceeding these levels during operation. TI does not warranty device operation under conditions in excess of the limits specified in the production data sheet. For informational purposes, an experiment was performed by exposing a population of BQ76952 devices to excessive voltage levels, with the results described in the following sections.