Texas Instruments BQ298218RUGR

Overview

BQ298218RUGR from Texas Instruments is a high-side battery protection IC for single-cell Li-ion/Li-polymer batteries, featuring integrated NFET drivers, ±18mV overcurrent-in-charge (OCC) detection, 40mV overcurrent-in-discharge (OCD), and 75°C internal overtemperature threshold with 15°C hysteresis. It supports 1mΩ sense resistors and operates in 1.5×1.5×0.37mm X2QFN package for smartphones and wearables.

For engineers reviewing the BQ298218RUGR datasheet, BQ298218RUGR pinout, BQ298218RUGR application, or BQ298218RUGR equivalent, key selection criteria include its factory-configured 4.20V overvoltage threshold, 2.50V undervoltage threshold with 125ms delay, CTR pin configurable for PTC-based external OT protection, and absence of 0V charging support-distinguishing it from BQ2980xx variants.

Technical Context

The BQ298218RUGR implements high-side protection using charge-pump-driven NFETs to maintain low Rdson across battery voltage range, enabling thermal efficiency in compact portable devices. Its current-sense architecture achieves ±1mV accuracy at 40mV OCD threshold and supports ultra-low 1mΩ sense resistors without sacrificing precision.

It features dual-mode CTR functionality: configured with 5MΩ internal pull-up for PTC-based overtemperature sensing (triggering FET shutdown when CTR voltage exceeds 1V), or host-controlled override for system reset/shutdown via timing-based logic (200µs activation, >5.4s for shutdown). UV shutdown is enabled, and ZVCHG is disabled per family specification.

Key Specifications

Pinout & Package

Package: 8-pin X2QFN (1.50 mm × 1.50 mm × 0.37 mm), wettable flank, 0.4-mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ298217RUGR and BQ298216RUGR, BQ298218RUGR provides balanced overvoltage/undervoltage thresholds (4.20V/2.50V), moderate 40mV OCD sensitivity, and mandatory UV shutdown-making it optimal for mainstream smartphones and wearables requiring predictable low-voltage cutoff and thermal margin.

Availability

BQ298218RUGR is available at Aetrix Electronics and suitable for smartphones, wearables, and power banks requiring stable component supply, precise single-cell Li-ion protection, and compact high-side FET control.

Supply support for BQ298218RUGR 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 company specializing in analog and embedded processing technologies, with leadership in power management and battery interface solutions.

The BQ298xx product line delivers integrated high-side protection for single-cell Li-ion batteries, designed specifically for space-constrained, thermally sensitive portable electronics requiring factory-configured, maintenance-free safety monitoring.

FAQ

What is the overvoltage protection threshold for BQ298218RUGR?

The BQ298218RUGR has a factory-configured overvoltage protection (OVP) threshold of 4.200 V with ±25 mV accuracy across –40°C to +85°C. This fixed value is laser-trimmed during manufacturing and cannot be adjusted externally. The OVP release hysteresis is 200 mV, meaning the battery voltage must fall below 4.000 V to re-enable the CHG FET after an OVP fault. This threshold is optimized for standard 4.2V Li-ion cells and ensures safe charging termination before cell stress occurs.

Does BQ298218RUGR support 0V charging?

No, BQ298218RUGR does not support 0V charging. As a member of the BQ2982xx family, zero-volt charging (ZVCHG) is explicitly disabled-unlike BQ2980xx variants. When VDD falls below the charge pump shutdown voltage (1.95 V), the CHG driver ceases operation and charging is blocked. This design prevents unsafe charging attempts on deeply depleted cells that may have degraded chemistry, aligning with JEITA guidelines for Li-ion safety in consumer electronics.

How is the CTR pin configured on BQ298218RUGR?

The CTR pin on BQ298218RUGR is factory-configured with a 5 MΩ internal pull-up resistor, enabling direct connection to an external PTC thermistor for secondary overtemperature protection. When the PTC resistance rises with temperature, the divided voltage at CTR exceeds 1 V (VIH), triggering immediate CHG/DSG FET shutdown. Unlike host-controlled reset mode, this configuration disables CTR's override function-no GPIO timing sequences are supported. The 5 MΩ value is selected to interface reliably with common 5kΩ–100kΩ PTCs at 70–85°C trip points.

What is the undervoltage shutdown behavior of BQ298218RUGR?

BQ298218RUGR implements enabled UV shutdown: when battery voltage drops below the 2.500 V threshold for 125 ms, the device enters 0.1 µA shutdown mode, turning off both CHG and DSG FETs and disconnecting the battery from load and charger. Recovery requires either reconnection of a charger (VPACK – VBAT > 700 mV typical) or battery recharge above 2.700 V (2.500 V + 200 mV hysteresis). This behavior preserves battery health during long-term storage and prevents deep discharge-induced copper shunting.

What sense resistor value is recommended for BQ298218RUGR's 40mV OCD threshold?

For the BQ298218RUGR's 40 mV overcurrent-in-discharge (OCD) threshold, a 1 mΩ sense resistor is recommended, enabling 40 A discharge current detection with ±1 mV accuracy. This value leverages the IC's support for ultra-low-resistance sensing while maintaining signal-to-noise ratio and minimizing I²R heating (<1.6 W at 40 A). Layout best practices require Kelvin connections to CS and VSS, symmetric trace routing, and avoidance of noisy digital traces near the sense node to preserve ±1 mV tolerance across temperature.