Texas Instruments BQ2050HSN-A508G4

Overview

BQ2050HSN-A508G4 from Texas Instruments is a lithium-ion battery fuel gauge IC that measures available capacity with ±1% typical accuracy across temperature and discharge rate, monitors voltage drop across a sense resistor (SR pin), drives five-segment LED indicators directly via LCOM/SEGx pins, and communicates over a 5-kb/s HDQ single-wire bus. It operates from the battery pack itself and supports self-discharge compensation, temperature-compensated charge counting, and pack-level protection supervision via CFC output.

For engineers reviewing the BQ2050HSN-A508G4 datasheet, BQ2050HSN-A508G4 pinout, BQ2050HSN-A508G4 application, or BQ2050HSN-A508G4 equivalent, key selection considerations include its 16-pin narrow SOIC package, 120 µA typical operating current, <100 nA data retention current, HDQ interface timing compliance, and support for graphite- or coke-anode Li-ion chemistries with programmable full-count thresholds.

Technical Context

The BQ2050HSN-A508G4 implements coulomb counting using integrated analog front-end circuitry to monitor voltage across an external sense resistor (SR–VSS), applying real-time compensation for temperature (−35°C to +85°C in 10°C steps), discharge rate (≥0.5C reduces available capacity by up to 10% for coke anode), and self-discharge (programmable from NAC16 to NAC2048 per day). Its internal registers-including NAC (Nominal Available Capacity), CACT (Temperature & Rate Compensated Available Capacity), DCR (Discharge Count Register), and LMD (Last Measured Discharge)-enable adaptive capacity learning during full discharge cycles.

It integrates LED display control (LCOM open-drain sink, SEG1–SEG5 dual-function outputs), HDQ serial communication (asynchronous return-to-one, LSB-first, 5 kb/s max), and pack protection supervision (CFC output disables charge FET when VSB exceeds NMCV register value or temperature falls outside 0–60°C). The device uses PROG1–PROG5 pins to configure PFC (Programmed Full Count), scale factor (1/80 to 1/2560 mVh/count), and self-discharge rate.

Key Specifications

Pinout & Package

Package: 16-pin narrow SOIC (SO-16N), 3.9 mm × 9.9 mm body, 1.27 mm pitch, RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar lithium-ion fuel gauge applications.

Compared with BQ2050HSN-A508G3, the BQ2050HSN-A508G4 delivers more accurate capacity estimation for graphite-anode cells due to optimized self-discharge and temperature compensation tables, while BQ2057W offers higher precision and expanded functionality at the cost of board-level redesign.

Availability

BQ2050HSN-A508G4 is available at Aetrix Electronics and suitable for smart power tools, medical portable devices, consumer electronics accessories, and industrial test equipment requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for BQ2050HSN-A508G4 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 decades of leadership in battery management ICs.

The BQ2050HSN-A508G4 belongs to TI's Power Gauge™ family of fuel gauge ICs, designed specifically for accurate, low-cost, single-chip Li-ion battery capacity monitoring in space-constrained portable systems.

FAQ

What is the primary function of the BQ2050HSN-A508G4?

The BQ2050HSN-A508G4 is a dedicated lithium-ion fuel gauge IC that performs real-time coulomb counting using a sense resistor, applies temperature- and discharge-rate-based compensation, learns battery capacity through full discharge cycles, and reports compensated available capacity (CACT) via HDQ interface or five-segment LED display. It does not provide charging control or protection switching.

How does the BQ2050HSN-A508G4 handle battery self-discharge compensation?

The BQ2050HSN-A508G4 applies self-discharge compensation using eight programmable rates (NAC16 to NAC2048 per day) selected by PROG5 pin logic level and temperature range. For example, at 20–30°C with PROG5 = L, it uses NAC512/day; the rate scales down at lower temperatures and up at higher ones per Table 5. Compensation is disabled if PROG5 = H.

Can the BQ2050HSN-A508G4 be used with both graphite- and coke-anode Li-ion batteries?

Yes - the BQ2050HSN-A508G4 supports both chemistries via PROG5 pin configuration: PROG5 = L selects graphite-anode compensation tables (Tables 3A/B), while PROG5 = Z selects coke-anode tables (Tables 4A/B). This affects discharge-rate and temperature correction factors applied to CACT and CACD registers.

What is the role of the CFC pin on the BQ2050HSN-A508G4?

The CFC (Charge FET Control) pin is an active-low open-drain output that disables the external charge FET when the battery voltage exceeds the NMCV register threshold or temperature falls outside 0–60°C. It interfaces directly with standard Li-ion protection ICs and requires an external pull-up resistor to VCC.

Does the BQ2050HSN-A508G4 require an external microcontroller to operate?

No - the BQ2050HSN-A508G4 operates autonomously: it powers from the battery pack, performs coulomb counting, updates NAC/CACT/LMD registers, drives LEDs directly, and manages self-discharge and temperature compensation without host intervention. An external MCU is only needed to read registers or reconfigure settings via HDQ.