100W Bidirectional Fast Charging Module – Charging & Discharging with Just One Type-C Cable
1. Product Positioning
Traditional one-way DC-DC can only "charge first, then discharge". In scenarios such as outdoor energy storage, power banks, and UPS, an additional charging board + boost board must be added, resulting in large size, low efficiency, and high cost. This 100W bidirectional fast charging module adopts a true bidirectional synchronous Buck-Boost architecture, where the same inductor and the same protocol MCU complete the seamless switching between "input charging / output discharging". With a full-load efficiency of 97% and a size of only 50 × 35 mm, this charging module supports 100W continuous output, helping developers instantly upgrade a 4-cell 21700 battery pack into a PD3.0 power bank, or upgrade an outdoor power supply into a "charge-while-discharge" UPS.
2. Core Solution
Main Control: Injoinic IP2368 (integrated PD3.0/PPS/QC4+ protocol + 14-bit fuel gauge)
Buck-Boost Driver: Southchip SC8812A (voltage resistance 36V, continuous current 10A, switching frequency 500kHz)
Power Stage: Two 5×6mm low-side MOS + 60A alloy integrated inductor, total R<sub>DS(on)</sub> 2.2mΩ, full-load temperature rise < 55℃
Protection Chain: Hardware OVP/OCP/OTP + software dual judgment, response time < 1µs, no external fuse required
3. Bidirectional Logic – 0ms Switching
Adapter Insertion: After the CC pin detects Source Capacity ≥ 60W, the bidirectional charging module automatically identifies it as "charging mode", charges the battery with a maximum of 20V⎓5A constant current/constant voltage, and turns off the external output at the same time.
Adapter Unplugging: When V<sub>IN</sub> drops < 1V and lasts for 50ms, the hardware comparator flips instantly, the SC8812A boosts reversely, and broadcasts 5V→20V externally within 200ms, allowing mobile phones/laptops to handshake 100W quickly.
Charge-While-Discharge (UPS): When the solar or vehicle-mounted input power ≥ load power, the module enters the "direct pass + supplementary charging" state. The input supplies the load first, and the remaining energy charges the battery, with zero power loss during switching. It is suitable for uninterrupted power supply of routers, NAS, and Raspberry Pi.
4. Performance Test Results (25℃ Environment)
Condition | Input | Output | Efficiency | Temperature Rise | Ripple |
20V⎓5A Output | 14.8V Battery | 20V⎓5A | 96.8% | 52℃ | 38mV |
20V⎓5A Charging | 20V Adapter | 14.8V⎓5A | 95.4% | 49℃ | 45mV |
12V⎓3A Output | 10.8V Battery | 12V⎓3A | 94.1% | 41℃ | 29mV |
Standby Power Consumption: 50µA (shutdown); 2.3mA (no-load maintaining PD broadcast)
5. Battery Compatibility
Lithium Battery: 2-6 cells (8.4-25.2V), supports NTC 10kΩ = 25℃ temperature protection
Lithium Iron Phosphate Battery: 2-6 cells (6.4-19.2V), voltage platform can be switched via resistor
Balancing Current: 50mA, built-in MOSFET realizes passive balancing, no external balancing board required
Fuel Gauge: 14-bit ADC, automatic internal resistance learning, battery capacity error ±1% after 3 cycles, capacity, current, temperature, and cycle times can be read through I²C 0x36 address
6. Protocol Support
PD3.0 Fixed Gear: 5V⎓3A / 9V⎓3A / 12V⎓3A / 15V⎓3A / 20V⎓5A
PPS: 3.3-21V, 20mV/step, maximum 5A
QC: QC2.0 5-12V; QC3.0 200mV/step; QC4+ compatible
Others: Samsung AFC 9V/12V, Huawei FCP 9V/12V, SCP 22.5W, MTK PE+ 2.0
Dual-Port Strategy: Single-port blind insertion 100W; if both ports are inserted at the same time, the power is automatically reduced to 65W + 30W, no external MCU intervention required
7. Mechanical & Installation
Size: 50 × 35 × 12 mm (excluding Type-C female socket height)
Positioning Holes: 4 × M2.5, 45 × 30 mm center distance, can be fixed with 3M adhesive or copper pillars
Heat Dissipation: 1.5W/(m·K) thermal pad on the top layer directly attached to the aluminum case, no fan required at full load; for >80W, it is recommended to attach a 5×5cm aluminum heat dissipation plate to the case
Interfaces:
USB-C1: Bidirectional input/output, 24-pin sink plate, supports 5A E-marker cable identification
USB-C2: Output-only, also 5A, internal current limit 3.3A
BAT+ / BAT-: 14 AWG pad, continuous 10A
SWD / I²C: 2.54mm 6P pin header, supports online firmware upgrade or custom voltage
8. Safety & Certification
Passed USB-IF PD3.0 TID Certification (Certificate No. 7077)
CE/FCC Class B Conduction/Radiation Margin > 6dB
4kV HBM ESD contact discharge, ±15kV air discharge without downtime
1500V isolation voltage (battery-shell), meeting IEC 62368-1 portable device requirements
