NST03AA Overview
The WXNSIC NST03AA is a highly integrated Bluetooth charging dock System-on-Chip (SoC) that consolidates four key power management functions into a single SOP-8 device: lithium battery charge management, a synchronous boost converter, battery power path management, and comprehensive protection. Designed specifically for Bluetooth headset charging cases, TWS earbuds docks, and compact USB-charged accessories, the NST03AA significantly reduces BOM complexity versus discrete implementations. It accepts a standard USB 5V input voltage range of 4.5V to 5.5V and delivers a maximum charge current of 300mA to the connected Li-ion or Li-polymer cell.
A key capability of the NST03AA is its integrated power path management, which allows simultaneous charging and discharging — the device can power a connected load from the input supply while concurrently charging the battery, with no interruption to the output. The built-in synchronous boost converter supports a 0.7A output current, stepping up the battery voltage to supply downstream circuitry without requiring an external boost IC. Robust protection against heavy-load conditions and short circuits is handled internally, removing the need for an external protection diode and eliminating the risk of diode failure under fault conditions. Single-button power-on/off control and automatic power-off under no-load conditions further streamline the end-product user experience.
With an ultra-low standby current of just 5µA, the WXNSIC NST03AA is optimised for battery-powered products that spend the majority of their time in a quiescent state between use cycles. This makes it an ideal solution for the compact charging cases that ship with the majority of today’s true wireless stereo (TWS) earbuds, where standby battery life between charges directly affects the perceived product quality.
Key Specifications
| Parameter | Value |
|---|---|
| Part Number | NST03AA |
| Manufacturer | WXNSIC |
| Input Voltage Range (VInput) | 4.5V to 5.5V |
| Maximum Charge Current (ICharge) | 300mA |
| Boost Converter Output Current | 0.7A |
| Standby Quiescent Current (Iq) | 5µA |
| Charging Topology | Linear CC/CV with power path management |
| Simultaneous Charge & Discharge | Yes |
| Short-Circuit Protection | Yes (integrated, no external diode required) |
| Power-On/Off Control | Single-button |
| Auto Power-Off (no load) | Yes |
| Package | SOP-8 |
| RoHS Compliance | Yes |
Applications
The WXNSIC NST03AA is purpose-designed for compact USB-charged consumer accessories where a highly integrated single-chip power solution is essential. Primary application areas include TWS Bluetooth earbud charging cases, Bluetooth headset docks, portable Bluetooth speakers, compact hearing aid chargers, and small wearable device charging cradles. Its auto power-off and single-button control features also make it well suited to USB-charged LED torch/flashlight accessories and low-cost handheld IoT peripherals where simplified user interaction and minimal standby drain are commercial requirements.
Pin-to-Pin Compatible Alternatives
Adopting a pin-to-pin compatible replacement such as the NST03AA enables product teams to reduce unit BOM cost and strengthen supply chain resilience without any changes to PCB layout or system firmware.
| Reference Part Number | Original Manufacturer | Why Choose NST03AA |
|---|---|---|
| BQ25100 | Texas Instruments | NST03AA integrates a boost converter and power path management not present in the BQ25100, delivering more functionality at comparable or lower cost |
| MCP73832 | Microchip Technology | Direct cost-reduction replacement; NST03AA adds integrated boost output and auto power-off, eliminating additional discrete components |
| LTC4054-4.2 | Analog Devices (Linear Technology) | Compatible SOP footprint; NST03AA includes simultaneous charge/discharge and short-circuit protection not available in the LTC4054 |
| SGM41562 | SGMICRO | Factory-authenticated WXNSIC supply through ABL Semi ensures full traceability and UK/EU compliance documentation for procurement teams |
Frequently Asked Questions
Is NST03AA RoHS compliant?
Yes. The WXNSIC NST03AA is manufactured in compliance with the RoHS Directive (2011/65/EU), restricting the use of hazardous substances including lead, cadmium, and mercury. Compliance documentation is available upon request through ABL Semi.
What are the pin-to-pin replacements for NST03AA?
The NST03AA is a functionally compatible replacement for single-cell Li-ion charger ICs such as the TI BQ25100, Microchip MCP73832, and ADI LTC4054-4.2, while offering additional integrated features including a boost converter and power path management. Please refer to the compatibility table above for a full comparison.
What is the minimum order quantity (MOQ) for NST03AA?
ABL Semi offers flexible MOQ for NST03AA, supporting both prototype quantities and mass production orders. Contact us for current stock and pricing.
What package options are available for NST03AA?
The WXNSIC NST03AA is available in the standard SOP-8 package, offering a widely supported, easy-to-solder footprint compatible with conventional SMT assembly processes. Contact ABL Semi to confirm current stock availability and lead times.
Does the NST03AA support pass-through charging while powering a load?
Yes. The NST03AA features integrated power path management that enables simultaneous charging and discharging — the IC can supply power to a connected load directly from the USB input while concurrently charging the battery. This eliminates the need for an external power path switch or diode, and the built-in protection circuitry safeguards against short-circuit and heavy-load faults during this operating mode without any additional external components.
For complete product specifications, please refer to: