Texas Instruments BQ29718DSER

Overview

BQ29718DSER from Texas Instruments is a single-cell Li-ion/Li-polymer battery protection IC that integrates overvoltage (4.425 V), undervoltage (2.500 V), charge/discharge overcurrent (–0.100 V / 0.100 V), and short-circuit (0.5 V) detection with factory-programmed thresholds and fixed timing delays (1.25 s OVP, 20 ms UVP, 8 ms OCD/OCC, 250 µs SCP). It operates from –40°C to +85°C with 4 µA normal-mode current and supports zero-voltage charging for deeply depleted cells in portable power systems.

For engineers reviewing the BQ29718DSER datasheet, BQ29718DSER pinout, BQ29718DSER application, or BQ29718DSER equivalent, this device delivers precision cell-level fault monitoring across external FETs with ±10 mV typical accuracy at 25°C, low-quiescent-current operation, and WSON-6 (1.5 mm × 1.5 mm) packaging optimized for space-constrained battery packs in handheld electronics.

Technical Context

The BQ29718DSER implements analog voltage sensing across external FETs (V– to VSS differential input) to detect discharge overcurrent (VOCD = 100 mV), charge overcurrent (VOCC = –100 mV), and short-circuit (VSCC = 500 mV), with dedicated gate drive outputs (COUT/DOUT) that transition low to disable CHG/DSG FETs upon fault trigger. Its internal oscillator enables programmable delay timers without external components.

All protection thresholds-including OVP (4.425 V), UVP (2.500 V), and recovery hysteresis-are factory-programmed and non-adjustable; fault detection relies on precise differential measurement rather than external sense resistors, and zero-voltage charging initiates when BAT–V– ≥ 1.7 V while inhibiting below 0.75 V.

Key Specifications

Pinout & Package

Package: WSON-6 (DSE), 1.50 mm × 1.50 mm × 0.75 mm body size, wettable flank terminals, exposed thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ29717DSER and BQ29723DSER, the BQ29718DSER provides the tightest discharge overcurrent detection (100 mV) with the fastest undervoltage response (20 ms), making it optimal for high-efficiency, low-R_DS(on) battery packs where rapid fault isolation is critical.

Availability

BQ29718DSER is available at Aetrix Electronics and suitable for smartphone battery packs, tablet PC power management, and handheld data terminal protection requiring stable component supply and long-lifecycle support.

Supply support for BQ29718DSER 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 over 50 years of innovation in battery management systems.

The BQ297xx family is designed specifically for cost-effective, highly integrated single-cell Li-ion/Li-polymer battery protection-targeting space-constrained, high-volume portable electronics where minimal external components and guaranteed safety compliance are essential.

FAQ

What is the overcharge protection voltage threshold for BQ29718DSER?

The BQ29718DSER has a factory-programmed overcharge detection voltage (VOVP) of 4.425 V with ±10 mV typical accuracy at 25°C. This threshold triggers the COUT output to go low after a fixed 1.25-second delay, disabling the charge FET to prevent cell damage. The value is laser-trimmed during manufacturing and cannot be adjusted externally.

Does BQ29718DSER support zero-voltage charging, and what are the conditions?

Yes, BQ29718DSER supports zero-voltage charging: it allows charging initiation when the BAT–V– voltage reaches ≥1.7 V, enabling recovery of deeply depleted cells. Charging is inhibited below 0.75 V to prevent lithium plating. This function operates autonomously without MCU intervention and is verified across the full –40°C to +85°C temperature range.

What package type and dimensions does BQ29718DSER use?

BQ29718DSER uses the WSON-6 (DSE) package: 1.50 mm × 1.50 mm × 0.75 mm body size with wettable flanks and an exposed thermal pad. It is a leadless, surface-mount package compatible with standard reflow processes and optimized for ultra-compact battery pack layouts where height clearance is constrained.

How does BQ29718DSER detect discharge overcurrent without a sense resistor?

BQ29718DSER detects discharge overcurrent by measuring the voltage difference between V– and VSS pins-effectively monitoring the V_DS of the external discharge FET. With a factory-set VOCD threshold of 100 mV, it triggers DOUT low within 8 ms when V––VSS exceeds this value, eliminating the need for external sense resistors and associated power loss.

What are the key differences between BQ29718DSER and BQ29717DSER?

BQ29718DSER and BQ29717DSER share identical OVP (4.425 V), UVP (2.500 V), and timing parameters, but differ in discharge overcurrent threshold: BQ29718DSER uses 100 mV while BQ29717DSER uses 130 mV. This makes BQ29718DSER more sensitive to low-magnitude discharge faults, ideal for low-R_DS(on) FET configurations in high-efficiency designs.