ZHCSDZ1E July 2015 – July 2024 TUSB4020BI
PRODUCTION DATA
The TUSB4020BI provides support for battery charging. Battery charging support can be enabled on a per port basis through the REG_6h(batEn[1:0]).
Battery charging support includes both charging downstream port (CDP) and dedicated charging port (DCP) modes. The DCP mode is compliant with the Chinese Telecommunications Industry Standard YD/T 1591-2009.
In addition to standard DCP mode, the TUSB4020BI provides a mode (AUTOMODE) which automatically provides support for DCP devices and devices that support custom charging indication. AUTOMODE is disabled by default. When in AUTOMODE, the port automatically switches between a divider mode and the DCP mode depending on the portable device connected. The divider mode places a fixed DC voltage on the ports DP and DM signals which allows some devices to identify the capabilities of the charger. The default divider mode indicates support for up to 5 W. The divider mode can be configured to report a high-current setting (up to 10 W) through REG_Ah(HiCurAcpModeEn). When AUTOMODE is enabled through REG_Ah(autoModeEnz), the CDP mode is not functional. CDP mode can not be used when AUTOMODE is enabled.
The battery charging mode for each port depends on the state of Reg_6h(batEn[n]), the status of the VBUS input, and the state of REG_Ah(autoModeEnz) upstream port, as identified in Table 6-1. Battery charging can also be enabled through the PWRCTL1/BATEN1 and PWRCTL2/BATEN2 pins.
batEn[n] | VBUS | autoModeEnz | BC Mode Port x (x = n + 1) |
---|---|---|---|
0 | Do not care | Do not care | Do not care |
1 | <4V | 0 | Automode(3) (4) |
1 | DCP(1) (2) | ||
>4V | 1 | CDP(1) |