STMicroelectronics STBC02BJR

Overview

STBC02BJR from STMicroelectronics is a highly integrated Li-Ion linear battery charger IC with embedded 150 mA LDO regulator, two 3 Ω SPDT load switches, smart reset/watchdog generator, and protection circuit module (PCM). It delivers up to 450 mA fast charge current, supports programmable floating voltage up to 4.45 V, and features automatic power path management and shipping mode (<10 nA battery leakage). It is designed for space-constrained wearable devices such as smartwatches.

For engineers reviewing the STBC02BJR datasheet, STBC02BJR pinout, STBC02BJR application, or STBC02BJR equivalent, key selection considerations include CC/CV charge termination accuracy, dual SPDT switch R_ON matching, LDO output voltage option (3.0/3.1/3.3 V), and integrated PCM thresholds for overcharge (4.275 V typ), over-discharge (2.8 V typ), and discharge overcurrent (900 mA).

Technical Context

The STBC02BJR implements a dual-stage CC/CV charging algorithm with independently programmable fast-charge (via ISET) and pre-charge (via IPRE) currents using external resistors. End-of-charge current defaults to 5% of IFAST but is configurable. Floating voltage is set via BATSNSFV resistor network, supporting up to 4.45 V with ±75 mV overcharge threshold tolerance.

Power path management dynamically selects SYS supply from IN or BAT based on input validity and battery state, while embedded PCM monitors battery voltage (BATSNS/BATMS), temperature (NTC), and discharge current to enforce OCP (900 mA), OVD (4.275 V), and UVD (2.8 V) protections. The SWIRE interface enables runtime control of BATMS monitoring and shutdown entry/exit.

Key Specifications

Pinout & Package

STBC02BJR is housed in a Flip Chip 30 package (2.25 × 2.59 mm, 0.4 mm pitch) with 30 bumps arranged in a 5×6 grid. Thermal resistance R_THJB is 50 °C/W on standard FR4 PCB.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Li-Ion linear charger with integrated LDO and protection applications.

Compared with BQ24075RTWR and MAX77818EWL+, the STBC02BJR uniquely combines linear charging, LDO, dual SPDT switches, hardware PCM, and sub-10 nA shipping mode in one Flip Chip 30 package - reducing total solution size by >40% and eliminating firmware dependency for critical safety functions.

Availability

STBC02BJR is available at Aetrix Electronics and suitable for smartwatches, fitness trackers, wireless earbud cases, and portable medical sensors requiring stable component supply, long shelf-life support, and compact power management integration.

Supply support for STBC02BJR 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and analog chips for industrial, automotive, and consumer markets.

The STBC02 belongs to ST's ultra-compact battery management IC product line, engineered specifically for space-constrained wearables and IoT edge devices needing integrated charging, regulation, protection, and low-leakage storage modes.

FAQ

What is the function of the SWIRE pin on the STBC02BJR?

The SWIRE pin is a dedicated serial control interface that enables runtime configuration of key safety and monitoring functions. It allows the host MCU to disable BATMS monitoring during normal operation to reduce system leakage, force entry into shutdown mode, and trigger wake-up from shipping mode. Unlike general-purpose GPIOs, SWIRE operates at LDO voltage level and uses a proprietary protocol defined in DS11617 Section 9.3.

How does the STBC02BJR handle battery temperature monitoring without an external ADC?

The STBC02BJR integrates an internal NTC bias current source (50 µA typ) and comparator circuitry to detect hot/cold thresholds (0.246 V and 1.355 V) corresponding to ~0 °C and ~45 °C for a 10 kΩ, β=3370 NTC. When temperature exceeds limits, charging halts and CHG toggles at 16.2 Hz. After charge completion, NTC pin enters high-Z state, allowing external MCU to reuse the same node for discharge-phase temperature logging.

Can the STBC02BJR's LDO output voltage be changed after soldering?

No. The LDO output voltage (3.0 V, 3.1 V, or 3.3 V) is factory-laser-trimmed and permanently set per order code (e.g., STBC02BJR = 3.3 V variant). It cannot be adjusted externally or reconfigured in-circuit. Designers must select the correct suffix during procurement - no resistor-divider or register-based adjustment is supported.

What happens to the SYS rail when the IN supply is disconnected and the battery is deeply discharged?

When VIN drops below V_UVLO (3.9 V) and V_BAT falls below V_ODC (2.8 V), the STBC02BJR enters over-discharge protection: SYS is actively pulled to GND via internal MOSFET, isolating the battery from all loads except the 10–50 nA shutdown current. This prevents further capacity loss and enables recovery only after WAKE-UP pin activation and V_BAT ≥ V_ODCR (3.0 V).