Texas Instruments BQ24314DSGT

Overview

BQ24314DSGT from Texas Instruments is a Li-ion battery front-end protection IC that provides input overvoltage (5.71–6.0 V), user-programmable input overcurrent (300–1500 mA), and battery overvoltage (4.30–4.40 V) protection in a space-saving 8-pin 2 × 2 mm WSON package. It integrates an internal power FET, fault status reporting via open-drain FAULT pin, and thermal shutdown for mobile phone and smart phone charging circuits.

For engineers reviewing the BQ24314DSGT datasheet, BQ24314DSGT pinout, BQ24314DSGT application, or BQ24314DSGT equivalent, key selection considerations include its 1-μs input OVP response time, programmable OCP threshold via ILIM resistor, 30-V absolute max input rating, and compatibility with 5-V AC adapters feeding Li-ion battery charging systems.

Technical Context

The BQ24314DSGT operates as a system-level safety monitor between the AC adapter and downstream charger IC, continuously sensing IN voltage, IN current (via ILIM resistor), and VBAT voltage. Its protection logic uses dedicated comparators with deglitch timers (e.g., 8-ms tDGL(PGOOD), 176-μs tDGL(BOVP)) and blanking periods (176-μs tBLANK(OCP)) to reject transients while ensuring reliable fault detection.

It implements three independent protection channels: input OVP with <1-μs propagation delay and 25–110-mV hysteresis; input OCP with user-set threshold (930–1070 mA at RILIM = 25 kΩ); and fixed 4.35-V battery OVP with 200–320-mV hysteresis. All faults drive the open-drain FAULT pin low and disable the internal pass FET.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ24316DSGT, the BQ24314DSGT offers tighter input OVP triggering for 5-V adapter ecosystems, while BQ24080DGQR trades programmability for integration-making BQ24314DSGT optimal for modular, serviceable, and adapter-agnostic portable designs.

Availability

BQ24314DSGT is available at Aetrix Electronics and suitable for smartphone charging protection, Bluetooth headset power safety, and MP3 player battery management requiring stable component supply and long-term industrial availability.

Supply support for BQ24314DSGT 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, embedded processing, and power management technologies with broad industrial and consumer design expertise.

The BQ24314DSGT belongs to TI's battery front-end protection product line, engineered specifically to safeguard Li-ion charging paths against adapter faults, overcurrent events, and battery overvoltage in portable electronics.

FAQ

What is the primary function of the BQ24314DSGT in a Li-ion charging system?

The BQ24314DSGT serves as a hardware-based safety monitor between the AC adapter and downstream charger IC. It continuously checks input voltage, input current, and battery voltage-and immediately disables its internal pass FET upon detecting overvoltage, overcurrent, battery overvoltage, or thermal overload. This prevents damage to the battery and system components. The BQ24314DSGT does not perform charging itself but ensures only safe power reaches the actual charger.

How is the input overcurrent threshold set on the BQ24314DSGT?

The input overcurrent threshold on the BQ24314DSGT is set by connecting an external resistor between the ILIM pin and VSS. The threshold follows IOCP ≈ 25 ÷ RILIM (with current in amperes and resistance in kΩ). For example, a 25-kΩ resistor sets IOCP to approximately 1000 mA. The BQ24314DSGT datasheet specifies a valid range of 15–90 kΩ, yielding 300–1500 mA thresholds. This resistor-based method allows precise, hardware-defined current limiting without software intervention.

Does the BQ24314DSGT support direct connection of the battery to the VBAT pin?

No-the BQ24314DSGT datasheet explicitly advises against direct connection of the battery to the VBAT pin. Instead, a series resistor (RBAT = 100–470 kΩ) must be used to isolate the battery. This is a safety requirement: in the event of an internal IC failure, up to 30 V could appear on VBAT. The resistor limits fault current to safe levels (e.g., ~246 μA at 100 kΩ), protecting the battery from hazardous conditions. The BQ24314DSGT's VBAT bias current is only 10 nA, so the voltage drop across RBAT remains negligible (<1 mV).

What happens when the BQ24314DSGT detects an input overvoltage condition?

When the BQ24314DSGT detects input voltage exceeding its 5.71–6.0 V OVP threshold, it turns off its internal pass FET within <1 μs, isolating OUT from IN. The open-drain FAULT pin is driven low to signal the fault. After the input voltage falls below VOVP minus hysteresis (25–110 mV), the device waits 8 ms (tON(OVP)) before re-enabling the FET-ensuring input stability. If 15 consecutive OVP events occur in one charge cycle, the FET latches off permanently until power is cycled or CE is toggled. This behavior is intrinsic to the BQ24314DSGT's hardware protection architecture.

Can the BQ24314DSGT be used with 9-V or 12-V adapters?

Yes-the BQ24314DSGT supports up to 30 V absolute maximum input voltage and operates over 3.3–26 V recommended input range, making it compatible with 9-V and 12-V adapters. However, its fixed 5.71–6.0 V input OVP threshold means it will trigger protection on those higher-voltage supplies unless configured for intentional overvoltage tolerance (e.g., using external clamping). For 9-V/12-V systems, the BQ24316DSGT (6.6–7.0 V OVP) is a more appropriate alternative. The BQ24314DSGT's specification and application notes confirm suitability only for nominal 5-V adapter environments.