Texas Instruments BQ29703DSER

Overview

BQ29703DSER from Texas Instruments is a single-cell Li-ion/Li-polymer battery protection IC that integrates overvoltage (4.425 V), undervoltage (2.300 V), charge/discharge overcurrent (–0.100 V / 0.160 V), and short-circuit (0.5 V) detection with factory-programmed thresholds and fixed delay timers. It drives external CHG/DSG FETs and supports zero-voltage charging for deeply depleted cells in portable power systems.

For engineers reviewing the BQ29703DSER datasheet, BQ29703DSER pinout, BQ29703DSER application, or BQ29703DSER equivalent, this device delivers precision ±5 mV OCP sensing across external FETs, ultra-low 4 µA NORMAL-mode current, and 100 nA shutdown quiescent draw - critical for battery runtime optimization in space-constrained handheld devices.

Technical Context

The BQ29703DSER implements analog voltage comparators with internal reference and programmable hysteresis to monitor BAT–VSS (OVP/UVP), V––VSS (OCD/SCP), and VSS–V– (OCC). Fault detection triggers independent timer-controlled gate drive outputs (COUT/DOUT) that transition low to disable external NMOS FETs.

Its differential sensing architecture enables accurate ±15 mV OCP threshold accuracy over –40°C to +85°C, while factory-programmed values - including 1.25 s OVP delay, 20 ms UVP delay, and 8 ms OCC/OCD delays - are permanently set and non-configurable in-system.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with BQ29702DSER and BQ29704DSER, the BQ29703DSER provides the most aggressive UVP cutoff (2.300 V) and shortest UVP delay (20 ms), making it optimal for high-drain portable devices where rapid cell protection under load is prioritized over runtime extension.

Availability

BQ29703DSER is available at Aetrix Electronics and suitable for smartphone battery packs, tablet PC secondary protection circuits, and handheld data terminal power management systems requiring stable component supply and long-term lifecycle support.

Supply support for BQ29703DSER 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, signal chain, and battery solutions.

The BQ297xx family is designed specifically for cost-sensitive, space-constrained single-cell Li-ion/Li-polymer battery packs in consumer electronics - delivering integrated, factory-programmed protection with minimal external components.

FAQ

What protection functions does the BQ29703DSER provide?

The BQ29703DSER provides overcharge protection (OVP at 4.425 V), over-discharge protection (UVP at 2.300 V), charge overcurrent protection (OCC at –0.100 V), discharge overcurrent protection (OCD at 0.160 V), and load short-circuit protection (SCP at 0.5 V). All thresholds and associated delay timers are factory-programmed and fixed. The BQ29703DSER executes these protections autonomously via dedicated COUT and DOUT gate drive outputs without MCU involvement.

Does the BQ29703DSER support zero-voltage charging?

Yes, the BQ29703DSER supports zero-voltage charging: it allows charging of fully depleted cells when the BAT–V– voltage reaches ≥1.7 V, and inhibits charging below 0.75 V to prevent lithium plating. This function is implemented in hardware and requires no external configuration. The BQ29703DSER enables safe recovery of deeply discharged Li-ion cells before normal operation resumes.

What is the package type and pin compatibility of BQ29703DSER?

The BQ29703DSER uses a 6-pin WSON (DSE) package measuring 1.50 mm × 1.50 mm × 0.75 mm with wettable flanks. Its pinout - BAT (5), COUT (2), DOUT (3), VSS (4), V– (6), NC (1) - is identical across the BQ297xx family. All variants share the same footprint and thermal characteristics, enabling direct substitution within the same package variant without PCB redesign.

How does the BQ29703DSER achieve accurate overcurrent detection?

The BQ29703DSER achieves ±15 mV OCD/OCC threshold accuracy over –40°C to +85°C using a precision differential input stage referenced to VSS and V–. It measures V_DS across the external discharge FET for OCD or V_SS–V_– for OCC, eliminating need for external sense resistors in many designs. The BQ29703DSER's ±5 mV typical sensing accuracy at 25°C ensures reliable current limiting even with FET R_DS(on) variation.

What are the key quiescent current specifications of BQ29703DSER?

The BQ29703DSER draws 4 µA typical current in NORMAL mode (BAT = 3.8 V) and ≤0.1 µA in shutdown mode. These ultra-low values minimize parasitic battery drain during storage and standby, directly extending shelf life and operational runtime. The BQ29703DSER maintains full protection functionality in NORMAL mode - no wake-up latency or initialization delay is incurred.