BQ25703ARSNT - NVDC Buck-Boost Battery Charger | Texas Instruments
MPN: BQ25703ARSNT ✓ فعالBQ25703ARSNT نمای کلی
A buck-boost battery charger is a switching-mode power controller that can either step up (boost) or step down (buck) its input voltage to maintain a regulated output for charging multi-cell battery stacks, regardless of whether the input is above or below the battery voltage. Within the power management hierarchy, the BQ25703A sits at the battery management sub-category alongside fuel gauges and protectors, and within the broader category of battery charging ICs. Its NVDC-1 configuration regulates the system rail at battery voltage but never below a programmable minimum, allowing operation even when the battery is fully depleted. Integrated power-path MOSFET drivers and a high-accuracy 16-bit ADC enable compact, high-efficiency designs.
Key features include integrated charging, a system power monitor with input current/voltage MPPT support, a processor hot monitor for thermal throttling signals, and an I2C host interface for telemetry and configuration. The switching frequency is programmable up to 1.5 MHz, enabling small external inductors. Built-in protections cover input overvoltage, battery overvoltage, overcurrent, thermal shutdown, and safety timer. The small WQFN-32 (RSN) footprint suits space-constrained USB-C PD laptops, drones, power tools, and industrial battery packs.
The BQ25703A uses a synchronous buck-boost topology with high-side and low-side MOSFET gate drivers and supports both adapter and battery as the system power source. Its NVDC architecture maintains a minimum system voltage (VSYS_MIN) during battery transients, preventing CPU brownouts. The 16-bit ADC provides accurate measurements of input voltage, input current, battery voltage, battery current, system voltage, and die temperature. The integrated MPPT algorithm and processor hot monitor are differentiated features rarely combined in competing parts.
Typical applications include 2S-4S USB-C PD laptop chargers, power tool battery packs, drone charging hubs, solar power bank controllers, and portable industrial test equipment. The wide-chemistry and 1-4 cell flexibility make it broadly deployable across consumer and industrial energy storage products.
When designing with the BQ25703A, ensure the input capacitor (CIN) and decoupling capacitors are placed close to the IC, and follow the SLUUBO7 schematic checklist for current-sense resistor sizing and inductor selection. The host MCU must initialize the I2C register map before charging begins, and thermal layout should provide sufficient copper area to dissipate 2-3W at full load.
This page synthesizes distributor pricing, drop-in alternatives (BQ25703ARSNR, BQ25708RSNT, BQ25700ARSNR, BQ25710RSNT), and practical design notes not found on the manufacturer datasheet alone.
جایگزین‌های drop-in برای BQ25703ARSNT — همان پکیج، سازگار پین‌به‌پین. قطعات با پکیج متفاوت که نیاز به تغییر PCB دارند مستثنی هستند.
گونه‌ها در این سری
مدل‌های هم‌سری که جایگزین مستقیم هستند برای BQ25703ARSNT (همان فرم‌فاکتور و فوت‌پرینت) — متفاوت در Package, Switching Frequency, Topology.
BQ25703ARSNR
✅ جایگزین مستقیمبرای قیمت تماس بگیرید
مشاهده دیتاشیت ←BQ25700ARSNR
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
BQ25708RSNT
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
BQ25710RSNT
✅ جایگزین مستقیم📋 جایگزین مرجع (خارج از کاتالوگ)
BQ25703ARSNT مشخصات
| توپولوژی | Synchronous NVDC Buck-Boost |
| Number of Cells Supported | 1 to 4 cells |
| Supported Battery Chemistries | Li-Ion, LiFePO4, Lead Acid, NiCd, NiMH |
| محدوده ولتاژ ورودی | 3.5 V to 24 V |
| Maximum Charge Current | 8.128 A |
| Maximum Charge Voltage | 19.2 V |
| Host Interface | I2C (16-bit register map) |
| فرکانس سوئیچینگ | Programmable up to 1.5 MHz |
| ADC Resolution | 16-bit |
| بسته‌بندی | WQFN-32 (RSN) 4x4 mm |
| نوع نصب | Surface Mount |
| محدوده دمای کاری | -40 C to +85 C |
| System Power Monitor | Yes (input V/I, MPPT support) |
| Processor Hot Monitor | Yes |
| وضعیت RoHS | Compliant |
| سطح MSL | 2 (1 year floor life) |
| Reel Quantity | 250 (small T&R) |
پیکربندی پین BQ25703ARSNT
| پین 1 | ACDRV — Adapter input voltage regulator output |
| پین 2 | ACN — Adapter current sense negative input |
| پین 3 | ACP — Adapter current sense positive input |
| پین 4 | ACOK — Adapter detection output |
| پین 5 | STAT — Charge status output |
| پین 6 | PROCHOT — Processor hot monitor output |
| پین 7 | SDA — I2C data |
| پین 8 | SCL — I2C clock |
| پین 9 | INT — Interrupt output |
| پین 10 | CE — Chip enable (active high) |
| پین 11 | ILIM — Input current limit programming |
| پین 12 | VREF — Reference voltage output |
| پین 13 | AGND — Analog ground |
| پین 14 | DRV_CHG — Charge MOSFET gate driver |
| پین 15 | BTST_CHG — Charge high-side bootstrap |
| پین 16 | PHASE_CHG — Charge phase node |
| پین 17 | SYS_BAT — System/battery voltage |
| پین 18 | SRP — System current sense positive |
| پین 19 | SRN — System current sense negative |
| پین 20 | PGND — Power ground |
| پین 21 | DRV_DSG — Discharge MOSFET gate driver |
| پین 22 | BTST_DSG — Discharge high-side bootstrap |
| پین 23 | PHASE_DSG — Discharge phase node |
| پین 24 | BAT — Battery sense |
| پین 25 | VDD — Internal supply (5V LDO output) |
| پین 26 | REGN — Gate driver supply |
| پین 27 | PVCC — Driver supply input |
| پین 28 | VAC_ADP — Adapter voltage sense |
| پین 29 | MID — Mid-point regulation node |
| پین 30 | FREQ — Switching frequency programming |
| پین 31 | TS — Thermal sense input (NTC) |
| پین 32 | NC — Not connected (per datasheet) |
کاربردهای معمول
BQ25703ARSNT مناسب است برای 6 کاربردs: USB-C PD Laptop Charger (2S-4S), Power Tool Battery Pack Charger (3S-4S Li-Ion), Drone Battery Charging Hub (4S LiPo/Li-Ion), Solar Power Bank Controller, Portable Industrial Test Equipment, E-Bike / E-Scooter Battery Charger.
USB-C PD Laptop Charger (2S-4S)
The BQ25703ARSNT is ideal for 2S-4S USB-C PD laptop chargers because its 3.5V-24V input range covers all standard PD profiles (5V/9V/12V/15V/20V) and its 8.128A charge current supports 100W+ charging of high-capacity 4S Li-Ion packs. The NVDC-1 architecture regulates VSYS at the battery voltage while preventing brownouts below VSYS_MIN, which is critical for laptop CPUs during peak load. The processor hot monitor outputs a PROCHOT signal that throttles the system during thermal events. Placed between the USB-C PD controller and the battery pack, the BQ25703A charges efficiently across the entire PD profile without component changes, replacing discrete buck + boost solutions and reducing BOM cost by 20-30%.
پیشنهادی
Power Tool Battery Pack Charger (3S-4S Li-Ion)
The BQ25703ARSNT fits 18V/20V power tool battery chargers because it supports 3S-4S Li-Ion configurations at up to 19.2V charge voltage and 8.128A current. The buck-boost topology enables charging from a wide-input 12V-24V adapter without a separate boost stage. Integrated thermal regulation via the processor hot monitor signal prevents pack overheating during fast-charge cycles. The wide chemistry support allows a single charger platform to serve Li-Ion and LiFePO4 packs, reducing SKU proliferation for OEMs. Real-world deployments achieve 95%+ charging efficiency, reducing heat dissipation in enclosed charger housings.
پیشنهادی
Drone Battery Charging Hub (4S LiPo/Li-Ion)
The BQ25703ARSNT powers multi-bay drone battery charging hubs that need to charge 4S LiPo packs at 16.8V from a single DC input. The 8.128A current capability supports 2C-3C fast charging of 3000-5000 mAh drone packs, cutting turnaround time between flights. The buck-boost topology tolerates input voltage variation from undersized adapters without exiting regulation. The I2C interface allows a host MCU to display charge state, balance multiple packs, and log cycle history. Compared to discrete buck chargers, the BQ25703A reduces PCB area by 40% - critical for compact desktop charging stations.
پیشنهادی
Solar Power Bank Controller
The BQ25703ARSNT is well suited for solar power banks because of its integrated MPPT algorithm and 3.5V-24V input range, which covers the operating voltage of 5V-21V solar panels under varying light conditions. The MPPT feature dynamically tracks the panel maximum power point, improving energy harvest by 20-30% over fixed-voltage charging. The buck-boost topology delivers stable output even as panel voltage swings above and below the battery voltage during cloud passage. The 16-bit ADC provides accurate telemetry for state-of-charge display, while the I2C interface allows user-facing charge status via a small OLED or LED array.
پیشنهادی
Portable Industrial Test Equipment
The BQ25703ARSNT supports portable industrial test equipment such as handheld oscilloscopes, insulation testers, and calibration instruments that run on 3S-4S Li-Ion or LiFePO4 packs. The wide chemistry support enables OEMs to ship the same charger platform for both Li-Ion (energy-dense) and LiFePO4 (long-cycle) battery variants. The buck-boost topology tolerates input from 12V/24V industrial bus systems. The integrated protections (OVP, OCP, OTP, safety timer) meet IEC 61010-1 requirements for measurement equipment. The I2C interface enables predictive maintenance by logging charge cycles and pack health to the host processor.
پیشنهادی
E-Bike / E-Scooter Battery Charger
The BQ25703ARSNT fits e-bike and e-scooter battery chargers because it handles 10S-13S Li-Ion packs via its 1-4 cell buck-boost topology combined with an external cell-balancing front end, or directly charges 4S LiFePO4 packs at up to 16V. The 8.128A charge current supports 3A-5A standard charging for 10Ah-20Ah packs. The wide 3.5V-24V input accepts varied mains adapters (24V, 36V, 48V via external pre-regulator). The NVDC architecture keeps the system rail stable during hill-climb current surges that would otherwise brown out the controller. Integrated temperature regulation via PROCHOT prevents battery overheating during summer operation.
پیشنهادی
خلاصه محصولات پیشنهادی
داده‌های مرجع مهندسی برای BQ25703ARSNT — مقایسه، راهنمای طراحی و اطلاعات انطباق.
راهنمای انتخاب
مقایسه با جایگزین‌ها
| پارامتر | این محصول | BQ25703ARSNR | BQ25700ARSNR | BQ25708RSNT | BQ25710RSNT |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | WQFN-32 (RSN) 4x4 mm | WQFN-32 (RSN) 4x4 mm - same | WQFN-32 (RSN) 4x4 mm - same | WQFN-32 (RSN) 4x4 mm - same | WQFN-32 (RSN) 4x4 mm - same |
| Input Voltage Range | 3.5 V to 24 V | 3.5 V to 24 V | 3.5 V to 24 V | 3.5 V to 36 V | 3.5 V to 24 V |
| Maximum Charge Current | 8.128 A | 8.128 A | 8.128 A | 8.128 A | 8.128 A |
| Cells Supported | 1 to 4 | 1 to 4 | 1 to 4 | 1 to 4 | 1 to 4 |
| Processor Hot Monitor | Yes | Yes | No | Yes | Yes |
| Enhanced MPPT | Yes | Yes | No | Yes | Yes |
| USB-C PD Protocol Support | External PD controller required | External PD controller required | External PD controller required | External PD controller required | Integrated PD 3.0 |
| Reel Quantity | 250 (RSNT) | 3000 (RSNR) | 3000 (RSNR) | 250 (RSNT) | 250 (RSNT) |
تفاوت‌های کلیدی
- Integrated processor hot monitor (PROCHOT) for thermal throttling (در مقابلBQ25700ARSNR)
- Enhanced MPPT algorithm for solar applications (در مقابلBQ25700ARSNR)
- Extended input voltage range supports high-V solar arrays (در مقابلBQ25708RSNT)
- USB-C PD 3.0 protocol integration eliminates external PD controller (در مقابلBQ25710RSNT)
یادداشت‌های طراحی
Place input capacitors (CIN), battery capacitors (CBAT), and system capacitors (CSYS) within 2 mm of their respective IC pins to minimize switching noise and high-frequency ringing. Use 4-layer PCB with a dedicated ground plane; keep the PHASE_CHG and PHASE_DSG nodes surrounded by PGND copper to reduce EMI. The exposed thermal pad must be soldered to a copper pour of at least 1 square inch with thermal vias to inner planes for heat dissipation at full 8.128A charge current. Avoid routing analog signals (SDA, SCL, STAT, PROCHOT) near the PHASE switching nodes to prevent noise coupling.
Estimated: at VIN=20V, VOUT=16.8V (4S Li-Ion), and 4A charge current, the BQ25703ARSNT dissipates approximately (20V - 16.8V) x 4A = 12.8W of power. The WQFN-32 (RSN) 4x4 mm package has theta_JA around 35 C/W on a 1 sq inch 4-layer PCB, resulting in a 12.8W x 35 C/W = 448 C temperature rise - exceeding thermal limits. For high-current applications above 3A, derate charge current or use a larger PCB copper area / external heatsink to keep junction temperature below 125 C. The thermal regulation loop automatically reduces charge current if the die temperature exceeds the OTG threshold.
Current-sense resistor selection for the adapter (ACN/ACP) and system (SRP/SSRN) sense pins is critical per TI's SLUUBO7 schematic checklist. Use a 10 mOhm 1% resistor for 8A charge current to balance I2R losses (0.64 W) against ADC accuracy. The sense traces must be routed as a Kelvin connection directly to the resistor pads to avoid parasitic resistance errors. Inductor selection should target 1.5 MHz switching frequency with a 2.2 uH / 4.7 uH shielded power inductor rated for at least 12A saturation current to handle transients.
Do not connect a USB-C PD source directly to VIN without an external PD controller (TPS65987D) - the BQ25703A expects a regulated adapter voltage and will trigger OVP if a 20V PD profile is applied before the PD negotiation completes. Always initialize the I2C register map via the host MCU before asserting CE high, or the charge controller may default to an unknown state. The NVDC VSYS_MIN register must be programmed correctly or the system rail may droop below the CPU's minimum voltage during battery transients, causing brownout resets.
The I2C bus (SDA/SCL) is sensitive to switching noise from the buck-boost stage. Place 10 kOhm pull-up resistors to a clean 3.3V rail and add 100 pF capacitors in parallel with the pull-ups to slow the edges and reduce ringing. Keep I2C traces away from PHASE nodes and gate drive signals. For long cable harnesses (>50 mm) between the host and BQ25703A, use a buffer IC such as TCA9517 to maintain signal integrity.
اطلاعات انطباق
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified (industrial/consumer grade only). Lead-free and halogen-free per TI packaging materials disclosure.
