Texas Instruments BQ24314CDSGR

Overview

BQ24314CDSGR from Texas Instruments is a Li-ion battery front-end protection IC that provides input overvoltage (OVP), user-programmable input overcurrent (OCP), and battery overvoltage (BVOVP) protection in a single 8-pin WSON package. It integrates an internal pass FET, monitors IN, OUT, VBAT, and ILIM terminals, delivers up to 1.5 A continuous current, responds to input OVP in <200 ns, and features thermal shutdown at 140°C - used in smartphone charging circuits to isolate faulty AC adapters before damage occurs.

For engineers reviewing the BQ24314CDSGR datasheet, BQ24314CDSGR pinout, BQ24314CDSGR application, or BQ24314CDSGR equivalent, key selection criteria include its 5.85 V ±15 mV input OVP threshold, programmable 300–1500 mA OCP range via external RILIM, 4.45 V battery OVP with 280 mV hysteresis, 170–280 mV dropout at 1 A, and open-drain FAULT signaling for host microcontroller fault coordination.

Technical Context

The BQ24314CDSGR implements independent analog comparators for input voltage (VOVP = 5.85 V), battery voltage (BVOVP = 4.45 V), and current-sense-derived overcurrent (IOCP set by RILIM). Its internal N-channel pass FET is controlled by dedicated protection logic with deglitch timers (tON(OVP) = 8 ms, tBLANK(OCP) = 176 µs) and fault counters that permanently disable the FET after 15 repeated faults per charge cycle.

It operates in three functional modes: OPERATION (FET ON when all parameters are within limits), POWER-DOWN (FET OFF below UVLO = 2.7 V), and POWER-ON RESET (soft-start with tDGL(PGOOD) = 8 ms delay before enabling). The CE pin enables host-controlled enable/disable with internal pulldown, and FAULT is an active-low open-drain output indicating any of four fault conditions.

Key Specifications

Pinout & Package

Package: 8-pin WSON (DSG), 2.00 mm × 2.00 mm body with exposed thermal pad connected internally to VSS.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar overvoltage and overcurrent protection applications.

Compared with TPS259210DRCR, BQ24314CDSGR provides essential battery overvoltage protection missing in the TI eFuse, making it mandatory for standalone Li-ion safety. Compared with BQ24315DSGR, it offers proven cost-optimized performance with slightly relaxed tolerances suitable for legacy designs where BVOVP and OVP accuracy margins are sufficient.

Availability

BQ24314CDSGR is available at Aetrix Electronics and suitable for smartphone charging circuits, Bluetooth headset power delivery, MP3 player battery safety systems, and PDA peripheral interface protection requiring stable component supply across high-volume consumer electronics production.

Supply support for BQ24314CDSGR 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 headquartered in Dallas, Texas, delivering analog and embedded processing solutions for industrial, automotive, personal electronics, and communications markets.

The BQ24314CDSGR belongs to TI's battery management IC portfolio, specifically designed to provide hardware-enforced front-end protection for Li-ion charging systems where reliability, speed, and multi-fault coverage are critical.

FAQ

What protection functions does the BQ24314CDSGR provide?

The BQ24314CDSGR provides four independent hardware-based protections: input overvoltage (OVP) with 5.85 V threshold and <200 ns response, user-programmable input overcurrent (OCP) from 300–1500 mA, battery overvoltage (BVOVP) at 4.45 V, and thermal shutdown at 140°C. Each fault drives the open-drain FAULT pin low and disables the internal pass FET. These functions operate autonomously without firmware, ensuring fail-safe behavior even if the host system is unpowered or locked up.

How is the overcurrent threshold set on the BQ24314CDSGR?

The overcurrent threshold on the BQ24314CDSGR is set by connecting an external resistor RILIM between the ILIM pin (Pin 7) and VSS. The relationship is approximated by IOCP ≈ 25 A·kΩ / RILIM, where RILIM must be between 15 kΩ and 90 kΩ to yield a valid 300–1500 mA trip point. For example, a 24.9 kΩ resistor sets IOCP to approximately 1000 mA. This resistor value directly determines both the initial current limit and the blanking time (tBLANK(OCP) = 176 µs).

Can the BQ24314CDSGR support reverse current flow for powering accessories?

Yes, the BQ24314CDSGR supports reverse current flow from OUT to IN for accessory powering, such as a smartphone supplying power to a Bluetooth headset. When VOUT exceeds UVLO + 0.7 V, the internal FET turns on, enabling low-drop conduction in reverse direction up to 1.5 A. However, no overcurrent protection is active in reverse mode, so external current limiting must be implemented if required. The device does not provide reverse-voltage or reverse-polarity protection.

What is the purpose of the RBAT resistor on the BQ24314CDSGR VBAT pin?

The RBAT resistor on the BQ24314CDSGR VBAT pin serves a critical safety function: it limits fault current if the IC fails and applies input voltage (up to 30 V) directly to the battery. TI recommends RBAT = 100–470 kΩ - high enough to restrict fault current to <250 µA yet low enough to keep voltage drop from VBAT bias current (≤10 nA) below 1 mV, preserving BVOVP accuracy. If battery overvoltage protection is not needed, VBAT may be tied directly to VSS.

Does the BQ24314CDSGR require external capacitors, and what are their roles?

Yes, the BQ24314CDSGR requires two mandatory 1 µF ceramic capacitors: CIN from IN to VSS and COUT from OUT to VSS. CIN suppresses input voltage spikes caused by cable inductance during load transients. COUT improves OVP response by providing local charge storage that triggers the current-limiting loop during fast-rising transients (<1 µs), reducing gate drive to the pass FET for faster isolation. Both capacitors must be placed adjacent to their respective pins with short, low-inductance traces.