ZHCSTD4B September 2019 – October 2023 BQ75614-Q1
PRODUCTION DATA
The BQ75614-Q1 device is standalone battery monitor that measures cell voltages, temperature, and current. The device supports 6 to 14 series-connected (6S to 14S) battery cells with two extra channels for fuse and relay diagnostic use or to extend for 16 series (16S) cell measurements.
The device is ASIL-D compliant on voltage, temperature, current measurements, and communication. All cell voltages are measured within 128 μs. Each cell sensing channel is included with a post-ADC digital low-pass filter (LPF) for noise reduction as well as providing moving average measurement results. The device has 8 GPIOs, all of which are configurable for NTC thermistor connections. All 8 GPIOs can be measured within 1.6 ms. An SPI master is available through GPIO configuration. The device has multiple fault detections. The NFAULT pin can be triggered to alert the MCU when a fault condition is detected.
The device supports passive balancing through an internal cell balancing MOSFET (CBFET) for each cell. The balancing function runs autonomously without microcontroller (MCU) interaction. It includes an option to pause and then resume balancing based on a programmable threshold detected by the external thermistor or if the die temperature is too high (greater than 105°C). Once balancing starts, the device tracks the balancing time on each cell. MCU can read out the remaining balancing time at any time.
The device includes a hardware OVUV comparator and an OTUT comparator with user configurable thresholds. These can be used as a second-level protector for cell over- and undervoltage and thermistor over- and undertemperature detections independent of ADC measurements.
The device has SLEEP and SHUTDOWN modes for lower power consumption. All functions work in ACTIVE mode, balancing and hardware comparators for OVUV and OTUT also work in SLEEP mode. While in SHUTDOWN, all active functions are turned off. A HW reset function is available and can be activated by the host MCU. The HW reset provides a POR-like event to the device without actual battery removal. This provides a reliable, low cost, and recoverable option to improve overall system robustness.