1. Overview & Functionality:

️· Device: HT4928S – a Power Management IC (PMIC) likely targeted for portable devices like power banks or battery chargers.
️· Key Features: Combines charging, boosting, and load detection/management functionalities. Designed for safe and efficient operation in battery-powered applications.
️· Multiple Operational Modes:
- Charging Mode: Supports 0.8A charging current with pre-charging for deeply discharged batteries. Implements a 3-stage charging process (trickle, constant current, constant voltage).
- Boost Mode (Step-Up): Provides a regulated 5.1V output with high efficiency (up to 91%). Features over-voltage and over-current protection.
- Load Detection: Automatically starts boost mode when a load > 10µA is detected. Shuts down after a 8-second delay with no load (load < 60mA).
- Pass-Through Charging: Enables simultaneous charging of the power bank and charging a connected device. Detects the presence of a charger and manages power distribution.
- LED Indicators: Uses LEDs (LD1, LD2) to indicate charging status, full charge, and load connection. Supports single or dual LED configurations.

2. Technical Specifications:

️· Charging:
- Charging Current: 0.8A
- Pre-charge Current: 10% of charging current
️· Boost:
- Output Voltage: 5.1V
- Output Current: Up to 0.8A
- Switching Frequency: 1 MHz
️· Protection:
- Over-Voltage Protection (OVP): 5.8V
- UVLO (Under Voltage Lockout): 2.95V (rising) / 3.20V (falling)
- OTP (Over Temperature Protection): 150°C
- Over-current protection & short circuit protection
️· Input & Output Parameters:
- Static Current (Iq): 13-30 µA
- Automatic Shutdown Load Current (Iauto_off): 60 mA
️· LED Indicators: LD1, LD2

3. Operational Details

️· Charging Status: LD1 and LD2 flash alternately during charging; LD2 remains lit when full. LD2 flashes during load connection and turns off after 8 seconds.
️· Pass-Through Charging: The IC detects charger presence using a 4ms pulse signal.
️· Automatic Shutdown: The boost converter disables after an 8-second delay without a connected load (below 40 mA).

4. Design Considerations:

️· Static Discharge Protection: Highlights the need for ESD prevention during manufacturing and handling.
️· PCB Layout: Instructions for component placement (C1, C2 close to the IC) and trace routing to minimize thermal impact and ensure signal integrity.

5. Ordering Information:

️· Part Number: HT4928S
️· Package: SOP8 (Pb-free)
️· Quantity: 4000 pieces per reel

6. Important Disclaimers:

️· The document is subject to change without notice. Consult the official website for the latest information.
️· No responsibility is assumed for issues related to patents or third-party rights.
️· Customer assumes responsibility for safety design and redundancy in applications.
️· Restricted use in human-related applications without explicit permission.
️· Constant improvement and advancement of product quality.



Please note: This summary provides a general understanding. Consult the complete datasheet for detailed specifications, application circuits, and full operational descriptions. The datasheet will contain critical information for proper device implementation and safety.