SC8905
High-efficiency 5A buck-boost battery charger with wide input voltage range and USB PD support for power bank applications
Product Overview
Description
The SC8905 is a high-efficiency synchronous buck-boost battery charger designed for high-power applications such as power banks and portable power stations. It supports up to 5A charge current with bidirectional power flow capability.
The device features a wide input voltage range of 4.5V to 22V, making it compatible with USB PD, Quick Charge, and various adapter sources. The buck-boost topology automatically transitions between buck and boost modes based on input and battery voltage conditions.
Integrated USB PD controller and comprehensive protection features make the SC8905 an ideal solution for modern power bank designs requiring high-power fast charging and discharging capabilities.
Product Series
SC
Primary Application
Power banks
Key Features
- 5A synchronous buck-boost charger
- Bidirectional power flow
- Wide input voltage range (4.5V-22V)
- USB PD 3.0 and QC support
- Up to 97% efficiency
- Integrated USB PD controller
- Comprehensive protection features
- QFN-32 package
Specifications
| Charge Current | Up to 5A |
|---|---|
| Charge Voltage | 4.2V/4.35V/4.4V programmable |
| Input Voltage | 4.5V to 22V |
| Efficiency | Up to 97% |
| Package | QFN-32 |
Applications
Power banks
Electronic system design
Portable power stations
Electronic system design
USB PD chargers
Battery and charging management
Battery backup systems
Battery and charging management
Industrial power systems
Industrial automation and control
FAE Expert Insights
"The SC8905 is SouthChip's flagship buck-boost charger for high-power applications. The 5A capability and 97% efficiency are impressive. The bidirectional power flow is perfect for power banks - it can charge the internal battery from USB and also discharge to power external devices. The integrated USB PD controller simplifies design significantly - no separate PD controller needed. The wide input voltage range handles everything from 5V USB to 20V USB PD. I've used this part in several 100W power bank designs with excellent results. Key design tips: use high-quality inductors (10μH, low DCR), ensure adequate input and output capacitance, and pay attention to thermal design at high power levels. The QFN-32 package provides good thermal performance with proper PCB layout. This is a premium solution for demanding power bank applications."
High-power buck-boost charger with USB PD and bidirectional power flow
— David Wang, BeiLuo
Frequently Asked Questions
What makes SC8905 suitable for USB PD applications?
The SC8905 is ideal for USB PD applications due to: (1) Wide input voltage range (4.5V-22V) supports all PD voltage levels (5V, 9V, 12V, 15V, 20V). (2) Integrated USB PD controller handles PD protocol communication. (3) High power capability (5A) supports up to 100W PD charging. (4) Bidirectional power flow enables both charging and discharging through USB-C. (5) Automatic voltage transition handles PD power contract negotiation seamlessly.
Contact LiTong for USB PD implementation guidance.
How does the buck-boost topology work?
The SC8905 buck-boost topology automatically selects operating mode: (1) Buck mode - When input voltage > battery voltage + margin, operates as step-down converter. (2) Boost mode - When input voltage < battery voltage, operates as step-up converter. (3) Buck-boost mode - Seamlessly transitions through 100% duty cycle region. (4) Automatic selection - Controller automatically selects optimal mode based on input and battery conditions. This flexibility allows charging from various sources regardless of voltage relationship to battery.
Contact LiTong for buck-boost converter design guidance.
What thermal considerations apply to SC8905?
Thermal design for SC8905 at high power: (1) Power dissipation - At 5A, even 97% efficiency means ~1.5W dissipation. (2) PCB copper area - Use large copper planes (1+ sq in) for heat dissipation. (3) Thermal vias - Array of thermal vias under QFN pad to spread heat. (4) Inductor selection - Low DCR inductor reduces conduction losses. (5) Airflow - Consider forced airflow for sustained high-power operation. (6) Thermal derating - Reduce current at high ambient temperatures. Proper thermal design is critical for reliable 5A operation.
Contact LiTong for thermal design and heat dissipation optimization.
FAQ 4 for SC8905?
This is additional FAQ information for SC8905. Contact LiTong for detailed technical support and application guidance. For more detailed information and application-specific guidance, please contact LiTong's technical support team. Our experienced FAEs can provide comprehensive assistance with product selection, design optimization, troubleshooting, and production support. LiTong is committed to helping you achieve the best results with SouthChip products in your applications.
Contact LiTong for technical support.
FAQ 5 for SC8905?
This is additional FAQ information for SC8905. Contact LiTong for detailed technical support and application guidance. For more detailed information and application-specific guidance, please contact LiTong's technical support team. Our experienced FAEs can provide comprehensive assistance with product selection, design optimization, troubleshooting, and production support.
Contact LiTong for technical support.