Texas Instruments BQ24315DSGR

Overview

BQ24315DSGR from Texas Instruments is a Li-ion battery front-end protection IC designed for mobile power management systems. It provides integrated overvoltage (5.85 V threshold), overcurrent (programmable 300–1500 mA), and battery overvoltage (4.35 V) protection with <1 µs OVP response, 5.5 V LDO-mode regulation, and thermal shutdown at 140°C. It serves as a safety-critical interface between AC adapters and charging circuits in compact portable devices.

For engineers reviewing the BQ24315DSGR datasheet, BQ24315DSGR pinout, BQ24315DSGR application, or BQ24315DSGR equivalent, this page delivers verified electrical parameters, validated terminal functions, confirmed 2×2 mm SON package mapping, real-world fault-handling behavior, and two rigorously cross-checked alternative parts for Li-ion front-end protection design.

Technical Context

The BQ24315DSGR implements a linear regulator architecture with an internal N-channel pass FET (Q1) that regulates OUT to 5.5 V when input voltage is between VO(REG) and OVP threshold. It continuously monitors IN voltage, ILIM-sensed current, and VBAT voltage using dedicated comparators and deglitched logic.

Protection is executed via hardware-level state machines: input overvoltage triggers immediate FET turn-off (<200 ns propagation delay); overcurrent initiates blanking (176 µs) followed by recovery (64 ms) or permanent shutdown after 15 faults; battery overvoltage induces soft-stop with hysteresis (275 mV). CE enables host-controlled enable/disable with internal pulldown.

Key Specifications

Pinout & Package

Package: 8-pin 2 mm × 2 mm SON (DSG) with exposed thermal pad electrically connected to VSS - requires PCB copper pour and thermal vias for reliable 1.5 A operation and thermal management.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Li-ion front-end protection applications.

Compared with BQ24315DSGR, BQ24313DSGR offers higher OVP tolerance but identical footprint and control logic, while TPS259211DRCR provides broader current range but omits battery voltage supervision and thermal protection - making BQ24315DSGR uniquely suited for safety-critical Li-ion front-end roles.

Availability

BQ24315DSGR is available at Aetrix Electronics and suitable for smartphone charging interfaces, Bluetooth headset power management, MP3 player adapter protection, and PDA system power path control requiring stable component supply across production lifecycles.

Supply support for BQ24315DSGR 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 expertise in battery safety and portable power solutions.

The BQ24315DSGR belongs to TI's battery front-end protection IC product line, engineered specifically to safeguard Li-ion cells against adapter-induced overvoltage, overcurrent, and thermal faults in space-constrained consumer electronics.

FAQ

What is the exact overvoltage protection threshold for BQ24315DSGR?

The BQ24315DSGR has a factory-trimmed input overvoltage protection (OVP) threshold of 5.85 V, with a guaranteed range of 5.71 V to 6.00 V across temperature and process variation. This value is fixed and cannot be adjusted externally - unlike the programmable overcurrent threshold set via the ILIM pin resistor. The OVP comparator responds within 200 ns to prevent downstream damage.

How does BQ24315DSGR handle battery overvoltage events?

When the voltage sensed at the VBAT pin exceeds 4.35 V, the BQ24315DSGR immediately disables the internal pass FET and drives the FAULT pin low. It remains latched off until the battery voltage drops below 4.075 V (4.35 V minus 275 mV hysteresis). Each event increments an internal counter; 15 consecutive faults trigger permanent shutdown until power cycle or CE toggle.

Can BQ24315DSGR support reverse current flow from OUT to IN?

Yes - when VOUT exceeds UVLO (2.7 V) plus hysteresis (260 mV), the BQ24315DSGR's internal FET turns on to allow reverse current up to 1.5 A, enabling accessory power delivery (e.g., USB OTG). However, no overcurrent protection is active in reverse mode, and the device relies on downstream circuitry for fault containment.

What is the recommended external resistor for setting 1 A overcurrent limit on BQ24315DSGR?

To set a 1 A input overcurrent limit, connect a 25 kΩ resistor between the ILIM pin and VSS. This follows the formula IOCP = 25 / R(ILIM), where R(ILIM) is in kΩ and IOCP is in amperes. TI specifies 24.9 kΩ as the standard value for 1 A, with tolerance impact limited to ±5% due to resistor and IC variation.

Does BQ24315DSGR require external components for basic operation?

Yes - BQ24315DSGR requires at minimum: (1) a 1 µF ceramic capacitor from IN to VSS, (2) a 1 µF ceramic capacitor from OUT to VSS, (3) a resistor from ILIM to VSS to set OCP, and (4) a pull-up resistor on FAULT for host monitoring. The CE pin may be grounded or left floating (internal pulldown), and VBAT requires a 100–470 kΩ safety resistor if used.