HW-357 Step-Up 18650 Li-Ion Power Bank Charger Module Type-C

HW-357 Step-Up 18650 Li-Ion Power Bank Charger Module Type-C (also known as the J5019 / 03962A Charger-Boost Combo Board) is a 2-in-1 single-cell lithium battery charger and adjustable DC-DC boost converter module. Combining a 1A TP4056 linear lithium-ion charger (with a modern USB Type-C input port and DW01A battery protection) alongside a high-efficiency MT3608 step-up regulator on a single compact PCB, it charges a 3.7V 18650/LiPo cell while simultaneously providing an adjustable 4.3V to 27V DC boosted output for 5V power banks, 9V/12V routers, and uninterrupted DC backup supplies.

Key Features:

• Integrated Charger + Adjustable Boost: Combines a 4.2V 1A single-cell Li-Ion charger, battery protection circuit, and a 4.3V–27V DC-DC boost converter on one compact board.
• USB Type-C & Solder Pad Input: Accepts 4.5V to 8V DC input via the onboard reversible USB Type-C socket or dedicated VIN+/VIN- solder pads.
• Multi-Turn Precision Potentiometer: Allows smooth adjustment of the boosted output voltage from 4.3V up to 27V DC (factory default is ~9V; turn counterclockwise to boost).
• Simultaneous Charge & Discharge (UPS Mode): Supports pass-through load sharing so connected 5V, 9V, or 12V devices stay powered seamlessly when external USB power is unplugged.
• Low Quiescent Standby Current: Consumes only ~0.5mA in unloaded standby mode, maximizing battery shelf life in portable instruments.

Technical Specifications:

• Model: HW-357 / J5019 Type-C 18650 Charger & Step-Up Boost Module
• Input Voltage Range: 4.5V to 8.0V DC (5V USB Type-C Nominal)
• Battery Charge Voltage & Current: 4.20V CC/CV at up to 1.0A
• Boost Output Voltage Range: 4.3V to 27.0V DC Continuously Adjustable (Default ~9V — verify with a multimeter before connecting a 5V load!)
• Max Reference Output Current: 5V at 1.4A, 9V at 0.8A, 12V at 0.6A (2A Peak Switch Rating)
• Quiescent Current: ~0.5 mA
• Onboard Protection: Overcharge (4.2V), Over-Discharge (2.5V), and Overcurrent Protection

Mechanical Specifications:

• PCB Material: FR-4 Double-Sided Fiberglass PCB
• Input Connector: USB Type-C Female Receptacle + VIN+/VIN- Solder Pads
• Battery & Output Terminals: Through-Hole Solder Pads (BAT+/BAT-, OUT+/OUT-)

Dimensions:

• Length: 33 mm
• Width: 23 mm
• Height: 5 mm
• Weight: ~4.5 g

Pinout and Wiring:

• USB Type-C / VIN+ & VIN-: 4.5V–8V DC charging supply input.
• BAT+ / BAT-: Connect to a 3.7V (4.2V full) 18650 Li-Ion or LiPo cell.
• OUT+ / OUT-: Regulated adjustable DC boost output (4.3V–27V). Always measure and set OUT+/OUT- voltage using the brass potentiometer before connecting sensitive 5V USB electronics.

Datasheet Reference:

• Primary ICs: TP4056 1A Linear Li-Ion Charger + MT3608 2A 1.2MHz Step-Up Converter Datasheet (PDF)

Commonly Used in:

• 5V, 9V, and 12V Uninterruptible Power Supplies (Mini Wi-Fi Router & Modem UPS)
• 9V Battery Replacement Packs for Digital Multimeters and Guitar Pedals
• Custom 5V Power Banks and Portable Microcontroller Power Rails
• Solar-Charged 5V/9V/12V Remote IoT Sensor Nodes

Applications:

• Converts a single 3.7V 18650 cell into a rechargeable 9V or 12V DC supply for handheld multimeters, wireless microphones, and network routers.
• Provides an all-in-one Type-C charging and 5V step-up power subsystem for ESP32, Arduino, and portable OLED display projects.
• Acts as a compact single-cell DC UPS that keeps security cameras or IoT gateways running without rebooting during mains power cuts.

Equivalent Models:

• Type-C USB 5V 2A Battery Charging Discharging Boost Module: Fixed 5V/9V/12V compact step-up charge/discharge board.
• LX-LBC3.1 Charging and Discharging 5V 3A Integrated Module Type-C: Fixed 5V 3A high-current integrated power bank module.

Package Includes:

• 1 × HW-357 Step-Up 18650 Li-Ion Power Bank Charger Module Type-C