My Inquiry
My Account
STMicroelectronics STC3115AIJT
- Part No.:
- STC3115AIJT
- Manufacturer:
- STMicroelectronics
- Category:
- Battery Management
- Package:
- 10-WFBGA, CSPBGA
- Datasheet:
-
STC3115AIJT.pdf
- Description:
- IC BATT MONITOR GAS GAUGE 10CSP
- Quantity:
- Payment:
- Shipping:
Inventory:63,074
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
STC3115AIJT from STMicroelectronics is a dedicated battery gas gauge IC for Li-ion/Li-polymer cells in handheld devices, integrating Coulomb counting, voltage-mode SOC estimation, and programmable low-battery alarm output. It delivers ±0.25% battery voltage monitoring accuracy, 45 µA power-saving mode current, and supports dual-package options: 1.4 × 2.0 mm 10-bump CSP and 2.0 × 3.0 mm DFN10 - used in mobile phones and portable medical equipment.
For engineers reviewing the STC3115AIJT datasheet, STC3115AIJT pinout, STC3115AIJT application, or STC3115AIJT equivalent, this device requires attention to its mixed-mode gas gauge architecture, I²C register-mapped configuration, ALM open-drain alarm behavior, and BATD/CD pin dual-role (battery detection + charge inhibit) in system-level battery management design.
Technical Context
The STC3115AIJT implements a hybrid gas gauge using both sigma-delta ADC-based Coulomb counting (14-bit, 500 ms conversion, 5.88 µV LSB) and voltage-mode algorithm with built-in OCV curve modeling. Its internal 32.768 kHz oscillator provides timing for synchronized voltage (250 ms), temperature (250 ms), and current (500 ms) conversions.
It operates in two configurable modes: mixed mode (VMODE = 0) enables concurrent current sensing and voltage/temperature sampling for high-accuracy SOC tracking; voltage-only mode (VMODE = 1) disables current sensing to reduce average current to 45 µA. Battery swap detection and robust initial OCV measurement are enabled via BATD/CD and RSTIO pins.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Gas Gauge Method | Mixed-mode: Coulomb counting + voltage-mode algorithm with adaptive OCV curve compensation for Li-ion/Li-Po aging and temperature drift. |
| Voltage Accuracy | ±0.25% at 25°C, ±0.5% over –20°C to +70°C - enables reliable SOC estimation from battery OCV without external calibration. |
| Current Sensing | 14-bit sigma-delta ADC, 5.88 µV LSB, supports 5–50 mΩ sense resistors - allows precise charge/discharge integration for high-rate battery usage. |
| Alarm Output | Open-drain ALM pin with dual-trigger: programmable SOC threshold (0.5% steps) and voltage threshold (17.6 mV steps) - enables system-level low-power shutdown or UI warning. |
| Power Modes | 45 µA avg. in power-saving mode; 2 µA max. standby; UVLO threshold 2.6 V ±0.1 V - ensures retention of RAM state during brown-out conditions. |
| Interface | I²C-compatible (up to 400 kHz), register-mapped control (25+ registers), no external clock required - simplifies host MCU integration with minimal GPIO overhead. |
| Temperature Sensing | Integrated sensor, ±3°C accuracy, –40°C to +125°C range, 1°C resolution - eliminates need for external thermistor in compact battery packs. |
Pinout & Package
STC3115AIJT is available in two micro-sized packages: 1.4 × 2.0 mm 10-bump Flip Chip CSP and 2.0 × 3.0 mm DFN10. Both share identical pin functionality and I/O mapping.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ALM | Open-drain alarm output | Drives low on low-SOC or low-voltage condition; requires external pull-up; software-clearable interrupt status. |
| SDA / SCL | I²C bidirectional data / clock | Standard I²C interface with 0.4 V logic-low (IOL = 4 mA); supports multi-device bus sharing. |
| CG | Analog current-sense input | Accepts ±40 mV differential voltage across sense resistor; 500 nA input bias enables high-precision shunt monitoring. |
| VIN | Analog battery voltage input | 0–4.5 V range, 2.20 mV LSB resolution; isolated ground path required for <±0.5% measurement accuracy. |
| BATD/CD | Bi-directional battery detect / charge inhibit | Input detects battery presence; output actively inhibits charging when asserted high - enables safe hot-swap handling. |
| RSTIO | Reset sense & control | Open-drain reset signal: monitors external reset line and can assert system reset via external circuitry. |
| GND | Analog/digital ground | Single-pin ground; layout requires separation from PCB power plane and exclusive connection to sense resistor for current accuracy. |
| VCC | Supply input | 2.7–4.5 V operation; includes internal UVLO (2.6 V) and POR; decoupling capacitor (1 µF) mandatory. |
Key Features
| Feature | Design Value |
|---|---|
| OptimGauge™ Algorithm | Proprietary mixed-mode SOC estimation that fuses Coulomb count and voltage-mode OCV tracking - eliminates long-term drift and adapts to battery aging without host intervention. |
| Programmable Dual Alarm | Independent thresholds for SOC (%) and battery voltage (V) stored in REG_SOC_ALM and REG_ALARM_VOLTAGE - enables staged low-battery response (warning → shutdown). |
| Battery Swap Detection | Hardware-assisted detection via BATD/CD pin and RSTIO synchronization - preserves SOC history across battery changes without host recalibration. |
| Robust Power-Up OCV | Advanced initialization sequence using BATD/CD and RSTIO to stabilize OCV reading before first SOC estimate - prevents erroneous "0%" reporting on cold start. |
| Low-Power Mixed Mode | 45 µA typical current in power-saving mode with voltage-only gas gauging - extends runtime in always-on portable devices while retaining SOC continuity. |
Applications
| Smartphone Battery Management | Digital Camera Power Monitoring |
|---|---|
|
Use Scenario: Real-time battery state tracking during video recording, flash charging, and display brightness adjustment. IC Role / Device Role / Timing Role: Primary gas gauge IC performing mixed-mode SOC calculation every 4 s, triggering ALM at 5% SOC to initiate graceful shutdown. Use Value: Prevents unexpected shutdown during capture; enables accurate remaining runtime prediction within ±3% error over full discharge cycle. |
Use Scenario: Monitoring Li-ion pack during burst-mode shooting and LCD playback with variable load profiles. IC Role / Device Role / Timing Role: Voltage-mode gas gauge active during idle; switches to mixed mode during flash charging to correct Coulomb counter drift. Use Value: Maintains SOC accuracy across intermittent high-current pulses without requiring host MCU polling or complex firmware compensation. |
| Portable ECG Monitor | Wireless Headphone Charging Case |
|
Use Scenario: Long-duration clinical-grade battery monitoring with strict safety-critical low-voltage cutoff. IC Role / Device Role / Timing Role: Dual-trigger alarm (3.2 V + 8% SOC) drives hardware reset to halt analog front-end before under-voltage damage occurs. Use Value: Meets IEC 62304 Class B requirements by providing deterministic, hardware-asserted low-power fault response independent of host firmware. |
Use Scenario: Estimating remaining charge cycles and battery health in compact TWS earbud cases with space-constrained PCB layout. IC Role / Device Role / Timing Role: Uses internal temperature sensor (±3°C) and voltage-mode algorithm to adjust SOC for ambient thermal effects during overnight charging. Use Value: Extends usable battery life by 12% over temperature-compensated-only solutions through adaptive OCV curve tuning. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar battery fuel gauge applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BQ27441-G1 (TI) | Higher integration: integrated sense resistor, 1% voltage accuracy, but no internal temperature sensor - requires external thermistor. | Targeted at cost-sensitive consumer wearables where board space > thermal accuracy; lacks BATD/CD pin for battery swap detection. | Select when minimizing BOM count is critical and thermal compensation is handled externally. |
| MAX17048 (Maxim) | ModelGauge™ m3 algorithm; 30 µA typical operating current; no programmable dual-alarm output - alarm is register-read only. | Suited for ultra-low-power IoT sensors; ALM pin absent - requires host polling or GPIO emulation for alert signaling. | Select when lowest quiescent current is primary and system-level interrupt handling is already implemented. |
Compared with BQ27441-G1 and MAX17048, the STC3115AIJT uniquely combines open-drain hardware alarm assertion, integrated temperature sensing, and battery swap detection - enabling simpler, safer, and more autonomous battery management in handheld medical and imaging devices without host firmware dependency.
Availability
STC3115AIJT is available at Aetrix Electronics and suitable for mobile phones, digital cameras, and portable medical equipment requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.
Supply support for STC3115AIJT 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, analog ICs, MEMS, and power management solutions for industrial, automotive, and consumer markets.
The STC3115 belongs to ST's battery management IC product line, engineered specifically for high-accuracy, low-power fuel gauging in space-constrained portable electronics - emphasizing autonomous operation, robust initialization, and seamless integration with resource-limited MCUs.
FAQ
What is the function of the BATD/CD pin on the STC3115AIJT?
The BATD/CD pin serves a dual role: as an input, it detects battery insertion/removal by sensing voltage level; as an output, it actively inhibits battery charging when driven high. This enables safe hot-swap capability and prevents charging of incompatible or defective batteries - critical for handheld medical and imaging devices meeting IEC 62366 usability requirements.
How does the STC3115AIJT handle battery aging over time?
The STC3115AIJT continuously compares Coulomb counter and voltage-mode SOC estimates, updating REG_CC_ADJ and REG_VM_ADJ registers with signed 16-bit correction factors (LSB = 1/512%). These adjustments automatically compensate for capacity loss and internal resistance increase, maintaining ±5% SOC accuracy over 300+ charge cycles without host recalibration or firmware updates.
Can the STC3115AIJT operate without a current-sense resistor?
Yes - the STC3115AIJT supports voltage-only gas gauging mode (VMODE = 1), disabling current sensing and reducing average current to 45 µA. In this mode, SOC is estimated solely from battery OCV using the built-in reference curve and temperature compensation, making it suitable for applications where shunt placement is impractical or power budget is extremely constrained.
What layout guidelines are critical for achieving ±0.25% voltage accuracy?
To achieve specified voltage accuracy, the VIN and GND pins must be routed with dedicated, isolated copper pours - VIN trace separated from main VBAT plane, and GND connected exclusively to the current-sense resistor's low-side node. Per AN4324, CG and GND traces require <2 mm length, no vias, and no shared return paths with digital or power circuits to avoid noise coupling into the 5.88 µV LSB ADC path.
STC3115AIJT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- OptimGauge™
- Package/Case:
- 10-WFBGA, CSPBGA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Battery Monitor
- Battery Chemistry:
- -
- Number of Cells:
- -
- Fault Protection:
- -
- Interface:
- I2C
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-CSP (1.4x2.04)
STC3115AIJT FAQ
1.How can I place an order for STC3115AIJT through Aetrix?
Please submit a Request for Quotation (RFQ) for STC3115AIJT on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for STC3115AIJT reliable?
The price and inventory of STC3115AIJT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STC3115AIJT is usually 5 days.
3.What payment methods are accepted for STC3115AIJT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STC3115AIJT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STC3115AIJT?
STC3115AIJT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STC3115AIJT order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for STC3115AIJT?
For technical support, including STC3115AIJT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STC3115AIJT requirements.
6.How does Aetrix verify that STC3115AIJT is sourced from the original manufacturer or authorized distributors?
All STC3115AIJT products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that STC3115AIJT meets industry standards.
7.What is the process for return or replacement of STC3115AIJT?
All STC3115AIJT units undergo pre-shipment inspection (PSI). If there is an issue with STC3115AIJT, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The STC3115AIJT part is unused and in its original packaging.
Return procedure for STC3115AIJT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
STC3115AIJT Tags
-
BQ29700DSER
Texas Instruments
-
S-8241ABKMC-GBKT2G
ABLIC Inc.
-
S-8241ABPMC-GBPT2G
ABLIC Inc.
-
BQ27427YZFR
Texas Instruments
-
BQ27426YZFR
Texas Instruments
-
STC3117IJT
STMicroelectronics
-
STC3115IJT
STMicroelectronics
-
BQ76925RGER
Texas Instruments
-
NPM1100-QDAA-R
Nordic Semiconductor ASA
-
BQ27441DRZR-G1A
Texas Instruments
-
STC3115AIQT
STMicroelectronics
-
S-8252AAL-M6T1U
ABLIC Inc.
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
