This reference design is an integrated USB Type-C® power delivery (PD) and charging reference design for 4- to 10-cell batteries for applications such as power tool chargers with a USB Type-C port, vacuum cleaners, portable power stations, and more.
The design incorporates the TPS25751 highly-integrated USB Type-C PD controller, which integrates a fully-managed robust power path switch inside to reduce size and external component. Configuring the power specification is easy, depending on the user’s application through a web-based GUI, thus reducing the design complexity. The PD controller works with the external battery charger controller BQ25756 through I2C communication. The BQ25756 supports a wide-range input with four-switch buck-boost configuration, and supports seamless transition from buck, boost, and buck-boost operation mode to provide a highly-efficient, highly-accurate, reliable charger. In addition to charging, the BQ25756 also support USB On-the-Go (OTG) mode with 5V, 9V, 15V, and 20V which is compatible with USB PD 3.0. This reference design can support charging batteries with maximum of 100W through a USB PD 3.0 compliance input source and provide a maximum 20V at 5A output in OTG mode. The high integration and simple design leads to lower BOM cost, a smaller size, and reduces time to market.
Table 1-1 shows the USB Type-C PD bidirectional charger specification; the USB Type-C port can be either a source or sink depending on the equipment plug in. The battery side supports 4- to 10-cells, the maximum charge current is limited to 3A. While in reverse mode, the output voltage is configured to 5V, 9V, 15V at 3A and 20V at 5A. The maximum output power is limited to 100W.
Parameter | Specifications |
---|---|
Sink voltage range | 5 to 20VDC |
Source voltage range | 5V, 9V, 15V, 20V |
Battery cell configuration | 4 to 10 Cells |
Maximum output current | Charge mode: 3A, Reverse mode: 5A |
Maximum power | 100W |
Switching frequency | 300kHz |
Efficiency | > 96% at full load |