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Texas Instruments BQ24040DSQR
- Part No.:
- BQ24040DSQR
- Manufacturer:
- Texas Instruments
- Category:
- Battery Chargers
- Package:
- 10-WFDFN Exposed Pad
- Datasheet:
-
BQ24040DSQR.pdf
- Description:
- IC BATT CHG LI-ION 1CELL 10SON
- Quantity:
- Payment:
- Shipping:
Inventory:4,945
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Product details
Overview
BQ24040DSQR from Texas Instruments is a single-input, single-cell Li-Ion/Li-Pol linear battery charger IC with integrated power FET, 4.20 V regulation voltage, 1% voltage accuracy, 10% current accuracy, and JEITA-compliant temperature monitoring via TS pin - designed for compact wearable devices such as TWS headsets and smartwatches requiring safe, autonomous charging without external microcontroller control.
For engineers reviewing the BQ24040DSQR datasheet, BQ24040DSQR pinout, BQ24040DSQR application, or BQ24040DSQR equivalent, key selection considerations include its 10-pin 2×2 mm² WSON package, programmable fast-charge current (10–1000 mA), fixed 10-hour safety timer, thermal regulation at 125°C, and functional safety capability per IEC 62368-1 CB certification.
Technical Context
The BQ24040DSQR implements a three-phase linear charging algorithm (pre-charge, constant-current, constant-voltage) with internal current-sense and voltage-regulation loops. It supports dual input sources (USB or AC adapter), dynamic power management (DPM) at 4.4 V, and input overvoltage protection at 6.6 V.
JEITA-based thermal regulation is enabled via a 10 kΩ NTC thermistor connected to the TS pin, triggering reduced charge current at cold (≤0°C) and hot (≥45°C) conditions and full disable above 60°C. The device enters TTDM mode when TS is pulled high (>1.6 V), disabling timers and termination while maintaining regulated output.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Charge Voltage Accuracy | ±1% - Ensures precise 4.20 V battery regulation, critical for Li-ion cell longevity and safety compliance. |
| Fast-Charge Current Range | 10–1000 mA - Programmable via external ISET resistor (540 Ω to 10.8 kΩ), enabling flexible design across low-power wearables. |
| Input Voltage Range | 3.5–28 V - Supports unregulated wall adapters and USB ports; DPM activates at 4.45 V to prevent input collapse under load. |
| Thermal Regulation Threshold | 125°C - Reduces charge current dynamically to maintain safe junction temperature during high-ambient or high-load operation. |
| Safety Timer Duration | Fixed 10 hours - Prevents indefinite charging in fault conditions; automatically resets on power cycle or battery removal. |
| JEITA Support | Enabled via TS pin - Implements Cold (≤0°C), Hot (≥45°C), and Disable (≥60°C) thresholds using 10 kΩ NTC, with defined voltage thresholds and hysteresis. |
| Functional Safety | IEC 62368-1 CB certified - Documentation available to support system-level functional safety analysis for consumer and medical applications. |
Pinout & Package
Package: 10-pin WSON (DSQ), 2.00 mm × 2.00 mm body size, exposed thermal pad connected to VSS.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| IN (Pin 1) | Power Input | Accepts 3.5–28 V DC from USB or adapter; includes 6.6 V overvoltage protection and DPM circuitry. |
| ISET (Pin 2) | Current Programming | Resistor-to-ground sets fast-charge current (KISET/RISET); supports 10–1000 mA range with ±10% accuracy. |
| VSS (Pin 3) | Ground Reference | Main ground return for all internal circuits and thermal pad connection point; must be low-impedance. |
| PRE-TERM (Pin 4) | Termination & Pre-charge Control | Resistor-to-ground programs both pre-charge current (2× termination) and termination threshold (5–50% of IOUT). |
| PG (Pin 5) | Power Good Indicator | Open-drain output low when IN > VUVLO + VIN-DT and VOUT > VUVLO; signals valid input source. |
| NC (Pin 6) | No Connect | Internally unused; must remain unconnected and un-routed on PCB. |
| ISET2 (Pin 7) | Input Current Limit Select | Digital input: High = 500 mA max (USB), Low = ISET-programmed current, Float = 100 mA max (USB enumeration). |
| CHG (Pin 8) | Charge Status Output | Open-drain output low during active charging; high-impedance when charging complete or disabled. |
| TS (Pin 9) | Temperature Sense Input | Biased with 50 μA current; monitors 10 kΩ NTC to enable JEITA profile and TTDM mode based on voltage thresholds. |
| OUT (Pin 10) | Battery Output | Charging output node; supports parallel system load; includes short-circuit detection (<0.8 V) and 1.4 A clamp limit. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated Linear Charger with Power FET | Eliminates external MOSFET and sense resistor; reduces BOM count and PCB area in space-constrained wearables. |
| Auto Start Function (TTDM Mode) | Enables production-line testing without battery: pulling TS >1.6 V disables termination/timers while maintaining regulated OUT voltage. |
| Dynamic Power Management (DPM) | Maintains minimum 4.45 V input voltage by reducing charge current when adapter sag occurs - prevents system brownout. |
| JEITA Temperature Compliance | Hardware-enforced charging behavior across -20°C to +60°C via TS pin, meeting IEC 62133 and UL 2054 thermal safety requirements. |
| Fixed 10-Hour Safety Timer | Hardwired timeout prevents overcharge in open-loop failure modes; non-adjustable but highly reliable for certified end products. |
Applications
| TWS Headsets | Smartwatches |
|---|---|
Use Scenario: Compact earbud charging case with USB-C input and dual Li-Po cells. IC Role / Device Role / Timing Role: Single-cell linear charger managing battery health, thermal safety, and USB current limiting during concurrent case charging and earbud top-up. Use Value: Enables fully autonomous charging with no MCU intervention, leveraging TTDM for factory test and JEITA for user-safety compliance. |
Use Scenario: Round-form-factor wristband with integrated 3.7 V Li-Po and ambient temperature exposure. IC Role / Device Role / Timing Role: Battery management unit providing cold/hot charge throttling, 4.20 V precision regulation, and 10-hour fail-safe timer. Use Value: Meets wearable thermal safety standards without software overhead; TS pin directly interfaces 10 kΩ NTC for hardware-only JEITA enforcement. |
| Wireless Speakers | Portable Medical Devices |
Use Scenario: Palm-sized Bluetooth speaker with USB-powered charging and audio playback during charge. IC Role / Device Role / Timing Role: System-side charger supporting parallel load (audio amp + battery) with DPM to avoid input collapse under peak audio load. Use Value: Maintains stable 5 V bus during simultaneous charging and playback; ISET2 pin enables USB 100/500 mA mode switching. |
Use Scenario: Handheld pulse oximeter with single-cell Li-Po, clinical-grade thermal monitoring, and long shelf life. IC Role / Device Role / Timing Role: Certified charging subsystem delivering IEC 62368-1 compliant power delivery with fixed safety timer and thermal shutdown at 150°C. Use Value: Functional safety documentation support simplifies regulatory submission; 1% voltage accuracy ensures consistent sensor calibration across battery cycles. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar single-cell Li-ion linear charger applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BQ24045DSQR | 4.35 V regulation voltage; same pinout, JEITA, and safety features; higher VOVP not applicable. | Targeted at high-voltage Li-Po or Li-CoO₂ chemistries requiring >4.2 V termination. | Select BQ24045DSQR only if battery chemistry mandates 4.35 V regulation; otherwise BQ24040DSQR provides optimal margin for standard 4.2 V cells. |
| BQ24041DSQR | No PRE-TERM or TS pins; adds BAT_EN and ASI/ASO for auto-start sequencing; 7.1 V VOVP. | Designed for systems with host MCU control and no NTC requirement; lacks JEITA and programmable termination. | Choose BQ24041DSQR when external logic manages charge enable/disable and thermal monitoring is handled elsewhere; not drop-in compatible due to pin function differences. |
Compared with BQ24045DSQR and BQ24041DSQR, the BQ24040DSQR uniquely balances precision 4.20 V regulation, full JEITA support, and programmable termination in a minimal footprint - making it the optimal choice for autonomous, safety-certified wearable chargers without host processor dependency.
Availability
BQ24040DSQR is available at Aetrix Electronics and suitable for TWS headsets, smartwatches, and portable medical devices requiring stable component supply, long-lifecycle availability, and certified safety compliance.
Supply support for BQ24040DSQR 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 leader specializing in analog and embedded processing technologies, with decades of expertise in power management ICs for portable electronics.
The BQ24040DSQR belongs to TI's BQ2404x linear charger family, engineered specifically for ultra-compact, battery-powered wearables demanding autonomous, safe, and certified charging without firmware overhead.
FAQ
What is the maximum input voltage rating for the BQ24040DSQR?
The BQ24040DSQR has an absolute maximum input voltage rating of 30 V on the IN pin, with built-in 6.6 V input overvoltage protection (VOVP) that disconnects the input path when exceeded. This allows robust operation with low-cost unregulated wall adapters while protecting internal circuitry from transient surges.
How does the BQ24040DSQR implement JEITA-compliant charging?
The BQ24040DSQR uses the TS pin to monitor a 10 kΩ NTC thermistor, interpreting voltage thresholds to enforce JEITA stages: normal charge (0°C–45°C), reduced current below 0°C and above 45°C, and full disable above 60°C. Thresholds like VTS-0°C (1.23 V) and VTS-45°C (0.278 V) are hard-coded in silicon with defined hysteresis.
Can the BQ24040DSQR charge a battery without a microcontroller?
Yes - the BQ24040DSQR operates autonomously: it initiates charging upon valid input, executes pre-charge/CC/CV phases, terminates based on programmed current threshold, and halts after 10 hours. No firmware or host control is required, making it ideal for cost-sensitive, MCU-less wearables.
What is the purpose of the TTDM mode in the BQ24040DSQR?
TTDM (Termination and Timer Disable Mode) activates when the TS pin voltage exceeds 1.6 V, disabling the safety timer and charge termination logic while maintaining regulated output. This enables production-line functional testing of the charging circuit without a battery installed - a key feature for automated manufacturing.
Does the BQ24040DSQR support USB 2.0 current limiting?
Yes - the BQ24040DSQR supports USB 100 mA and 500 mA input current limits via the ISET2 pin: floating selects 100 mA (for USB enumeration), high selects 500 mA (full USB power), and low follows the ISET-programmed current. This meets USB specification requirements without external switches.
BQ24040DSQR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 10-WFDFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Battery Chemistry:
- Lithium Ion/Polymer
- Number of Cells:
- 1
- Current - Charging:
- Constant - Programmable
- Programmable Features:
- Current
- Fault Protection:
- Over Temperature, Over Voltage, Short Circuit
- Charge Current - Max:
- 1A
- Battery Pack Voltage:
- 4.2V
- Voltage - Supply (Max):
- 28V
- Interface:
- -
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-WSON (2x2)
BQ24040DSQR FAQ
1.How can I place an order for BQ24040DSQR through Aetrix?
Please submit a Request for Quotation (RFQ) for BQ24040DSQR 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 BQ24040DSQR reliable?
The price and inventory of BQ24040DSQR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BQ24040DSQR is usually 5 days.
3.What payment methods are accepted for BQ24040DSQR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BQ24040DSQR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BQ24040DSQR?
BQ24040DSQR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BQ24040DSQR 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 BQ24040DSQR?
For technical support, including BQ24040DSQR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BQ24040DSQR requirements.
6.How does Aetrix verify that BQ24040DSQR is sourced from the original manufacturer or authorized distributors?
All BQ24040DSQR 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 BQ24040DSQR meets industry standards.
7.What is the process for return or replacement of BQ24040DSQR?
All BQ24040DSQR units undergo pre-shipment inspection (PSI). If there is an issue with BQ24040DSQR, 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 BQ24040DSQR part is unused and in its original packaging.
Return procedure for BQ24040DSQR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BQ24040DSQR Tags
-
BQ21040DBVR
Texas Instruments
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MCP73812T-420I/OT
Microchip Technology
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MCP73831T-2ACI/OT
Microchip Technology
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MCP73832T-2ACI/OT
Microchip Technology
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MCP73831T-2DCI/OT
Microchip Technology
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MCP73832T-2DCI/OT
Microchip Technology
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MCP73831T-2ATI/OT
Microchip Technology
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MCP73832T-2ATI/OT
Microchip Technology
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MCP73831T-5ACI/OT
Microchip Technology
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MCP73832T-2ACI/MC
Microchip Technology
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MCP73831T-2ACI/MC
Microchip Technology
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MCP73831T-2ATI/MC
Microchip Technology
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