Texas Instruments BQ7791514PWR

Overview

BQ7791514PWR from Texas Instruments is a stackable ultra-low power primary protector IC for 3- to 5-series Li-ion/Li-polymer battery packs, implementing autonomous voltage (±10 mV OV/±18 mV UV accuracy), current (OCD1: –2500 mV threshold), and temperature protections without MCU control. It integrates independent CHG/DSG low-side NMOS drivers and smart passive cell balancing (up to 50 mA) with HIBERNATE mode (2 µA). Used in e-bikes and power tools requiring robust, maintenance-free pack protection.

For engineers reviewing the BQ7791514PWR datasheet, BQ7791514PWR pinout, BQ7791514PWR application, or BQ7791514PWR equivalent, key selection factors include its factory-programmed 3.65 V overvoltage threshold, 2.5 V undervoltage threshold, 65°C/50°C discharge/charge overtemperature limits, and TSSOP-24 package compatibility with stacked multi-device architectures.

Technical Context

The BQ7791514PWR implements a fully autonomous protection architecture with no host controller required: voltage sensing across up to five cells (VC0–VC5), bidirectional current monitoring via SRP/SRN, and thermistor-based temperature detection using TS/VTB. Its stackable interface enables scalable configurations-single device supports 3–5 series; cascaded devices extend to ≥20 series using LPWR/PRES and CBO/CBI signaling.

Protection logic uses factory-trimmed thresholds and resistor-programmable delays (e.g., OCDP pin sets OCD1/OCD2 delay); fault recovery is load-removal only for OCD1/OCD2/SCD. The integrated cell-balancing algorithm activates based on voltage hysteresis (100 mV VHYST) and step voltage (50 mV VSTEP), enabling selective balancing of odd/even cell groups every 521 ms.

Key Specifications

Pinout & Package

TSSOP-24 package (7.70 mm × 4.40 mm), 0.65 mm pitch, exposed thermal pad (not electrically connected). Designed for surface-mount assembly with standard reflow profiles and thermal management via PCB copper area under the pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar battery protection applications.

Compared with BQ7791514PWR, BQ7791506 offers tighter overvoltage control for LFP chemistries but lacks the 2.5 V UV threshold needed for high-voltage NMC; BQ7791508 provides longer fault delays for mechanical-load inertia but increases risk of thermal runaway in fast-fault scenarios.

Availability

BQ7791514PWR is available at Aetrix Electronics and suitable for power tools, e-bikes, and robotic cleaners requiring stable component supply, long-term lifecycle support, and automotive-grade reliability in 10.8-V to 72-V battery systems.

Supply support for BQ7791514PWR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of battery management system expertise.

The BQ77915 family delivers autonomous, stackable protection for multi-cell Li-ion packs - designed specifically for cost-sensitive, high-volume portable power applications where MCU-free operation and ultra-low quiescent current are critical.

FAQ

What is the overvoltage protection threshold of the BQ7791514PWR?

The BQ7791514PWR has a factory-programmed overvoltage threshold of 3.65 V per cell with ±10 mV accuracy at 25°C. This value is fixed and not user-adjustable; it is optimized for NMC/NCA lithium-ion cells to prevent electrolyte decomposition while maximizing usable capacity. The BQ7791514PWR does not support external resistor programming of OV threshold.

Does the BQ7791514PWR support 6-series or higher battery configurations?

The BQ7791514PWR natively supports 3- to 5-series configurations. For 6-series and above, multiple BQ7791514PWR devices must be stacked using the LPWR/PRES and CBO/CBI interfaces. Each additional device adds five more cell monitoring channels; up to four devices support ≥20-series stacks. Cascading requires careful delay budgeting per the datasheet's timing tables.

How does the HIBERNATE mode function on the BQ7791514PWR?

HIBERNATE mode on the BQ7791514PWR reduces quiescent current to 2 µA by disabling all protection monitoring except PRES pin wake-up detection. It is entered when the PRES pin is left floating and exited when PRES is driven high (>1.5 V). During HIBERNATE, cell balancing and fault responses are suspended; the BQ7791514PWR resumes full operation within 10 ms of wake-up.

Can the BQ7791514PWR perform cell balancing without external components?

Yes, the BQ7791514PWR performs passive cell balancing autonomously using integrated FETs capable of 50 mA per cell. No external FETs, resistors, or controllers are required for balancing currents ≤50 mA. External FETs are optional for higher balancing currents or thermal dissipation requirements, controlled via the CBI/CBO interface.

What is the purpose of the OCDP pin on the BQ7791514PWR?

The OCDP pin on the BQ7791514PWR programs the detection delay for overcurrent discharge 1 (OCD1) and overcurrent discharge 2 (OCD2) faults. A resistor connected from OCDP to VSS selects one of eight factory-defined delay options (5 ms to 1420 ms). For stacked configurations, upper devices use a 10-MΩ resistor to disable local OCD delay and inherit timing from the bottom device.