Texas Instruments BQ2002GPN

Overview

BQ2002GPN from Texas Instruments is a CMOS NiCd/NiMH fast-charge management IC designed for single-cell or multi-cell battery charging systems. It provides five independent fast-charge termination methods (–∆V, PVD, max voltage, max temperature, max time), integrated top-off and pulse-trickle control, and direct LED status indication. It operates from 4.0–6.0 V supply and supports temperature-sensing via NTC thermistor on TS pin.

For engineers reviewing the BQ2002GPN datasheet, BQ2002GPN pinout, BQ2002GPN application, or BQ2002GPN equivalent, key selection criteria include its –∆V/PVD dual-mode voltage termination, TM-pin-configurable timing limits (160 min fast-charge at C/2), open-drain CC/LED outputs, and compatibility with 8-pin DIP or narrow SOIC packages in commercial and extended temperature ranges.

Technical Context

The BQ2002GPN implements a state-machine-based charge controller with synchronized voltage sampling-triggered by INH pulses or free-running every 17 s-to reject 50/60 Hz ripple during –∆V and PVD detection. Its analog front-end includes high-impedance BAT input (≥50 MΩ) and TS input (≥50 MΩ) for precision battery voltage and thermistor-based temperature monitoring.

Termination logic combines digital thresholds (e.g., VMCV = 2.0 V ±5%, VTCO = 0.5×VCC ±5%) with analog delta detection (–∆V = –12 mV ±3 mV, PVD = –2.5 mV ±2.5 mV), while the TM pin selects among three discrete configurations for fast-charge duration, top-off rate, and hold-off timing-all without external components.

Key Specifications

Pinout & Package

Package: 8-pin 300-mil DIP (PN suffix); body dimensions 0.380" × 0.325" × 0.180" (9.65 mm × 8.26 mm × 4.57 mm); lead finish NIPDAU; RoHS compliant; MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NiCd/NiMH charge management applications.

Compared with BQ2002E and BQ2002GSN, the BQ2002GPN offers identical core functionality in through-hole DIP packaging with 160-minute C/2 fast-charge limit - making it optimal for prototyping, service replacement, and legacy through-hole production where board real estate and manual assembly are constraints.

Availability

BQ2002GPN is available at Aetrix Electronics and suitable for portable medical devices, two-way radios, consumer cordless phones, and emergency lighting systems requiring stable component supply and long-term obsolescence support.

Supply support for BQ2002GPN 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, specializing in analog, embedded processing, and power management technologies with over 90 years of innovation in industrial, automotive, and consumer electronics.

The BQ2002GPN belongs to TI's battery management IC portfolio, engineered specifically for cost-sensitive, standalone NiCd/NiMH charging applications where reliability, safety, and minimal external component count are critical design requirements.

FAQ

What is the maximum number of NiCd/NiMH cells the BQ2002GPN can manage?

The BQ2002GPN is designed for single-cell voltage monitoring (2.0 V max), but supports multi-cell packs via external resistor divider on the BAT pin. For an N-cell pack, the divider ratio must be RB1/RB2 = N – 1 to scale total pack voltage down to ≤2.0 V at BAT. Input impedance must remain ≥200 kΩ and <1 MΩ to ensure accuracy and stability. The BQ2002GPN itself does not limit cell count - the external network and thermal sensing placement determine safe operation.

How does the BQ2002GPN handle AC line ripple during –∆V detection?

The BQ2002GPN uses synchronized voltage sampling triggered by falling edges on the INH pin to reject 50/60 Hz ripple. Each sample averages 32 measurements (PVD) or 16 measurements (–∆V) taken 57 µs apart, resulting in effective filtering centered at 55 Hz or 109 Hz. If INH is unused, sampling defaults to free-running every 17 seconds - still sufficient to avoid false triggers in most low-noise supplies. This architecture ensures robust –∆V detection without external op-amps or filters in the BQ2002GPN design.

Can the BQ2002GPN be used with lithium-ion batteries?

No, the BQ2002GPN is not suitable for lithium-ion batteries. Its termination algorithms - –∆V, PVD, and 2.0 V/cell maximum voltage - are specific to NiCd/NiMH electrochemistry. Li-ion requires constant-current/constant-voltage regulation, 4.2 V/cell precision, and different thermal and voltage safety thresholds. Using the BQ2002GPN with Li-ion poses serious overcharge, thermal runaway, and safety risks. TI recommends dedicated Li-ion chargers such as the BQ2407x or BQ256xx families instead of the BQ2002GPN.

What is the function of the TM pin in the BQ2002GPN, and how is it configured?

The TM pin on the BQ2002GPN is a three-level analog input that configures fast-charge duration (40/80/160 min), top-off rate, PVD/–∆V mode, and voltage hold-off time. It is set using a resistor divider between VCC and VSS: low (<0.1 V), mid (VCC/2 ±0.5 V), or high (>VCC – 0.5 V). Mid-level (e.g., 2.5 V on 5 V rail) selects 160-min C/2 fast-charge and PVD mode in the BQ2002GPN - matching the default configuration shown in Table 1 of the datasheet.

Does the BQ2002GPN require external components for basic operation?

Yes, the BQ2002GPN requires four minimum external components for functional operation: (1) a resistor divider on BAT to scale multi-cell battery voltage to ≤2.0 V, (2) an NTC thermistor + pull-up resistor on TS for temperature monitoring, (3) a current-limiting resistor on LED for status indication, and (4) a decoupling capacitor (≥0.1 µF) on VCC. No external timing capacitors or op-amps are needed - all timing, references, and comparators are integrated, making the BQ2002GPN a true single-chip solution.