STCC2540 Datasheet, PDF (3/32 Pages) STMicroelectronics – USB charging controller with integrated power switch

STCC2540
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Functional description
Functional description
The STCC2540 device integrates, in one package, a complete solution to charge portable
devices through USB ports, including:
• Charger emulator compatible with USB battery charging BC1.2 standard, Chinese
telecommunications standard YD/T 1591-2009 and proprietary charger such as Apple^®
divider mode, BlackBerry^® and Korean tablet charging mode.
• 3 control pins, CTL1, CTL2, CTL3 allowing the host to select the emulation profile.
These pins may be controlled directly from the host USB controller or from the
embedded controller.
• USB data switch with wide bandwidth up to 1100 MHz compliant with USB 2.0
standard. This wide bandwidth switch features low capacitance and low R_ON
resistance, allowing signals to pass with minimum edge and phase distortion.
• N-channel power switch with low R_ON resistance of 65 mΩ typ., high current limiter
accuracy and high current output capability, 2.5 A typ. The current limit threshold can
be adjusted with a good accuracy by an external resistor in the range 500 mA to 2.8 A
(max.).
Constant current mode protection is used to protect the device and the host system
against overcurrent or short-circuit. Other protection includes reverse current and
reverse voltage protection, undervoltage lockout and thermal shutdown.
• A deglitched output (FAULT) reporting the failure events of overcurrent, thermal
shutdown and reverse current (backdrive) to V_IN.
• Charging current sensing circuit. The output CHARGING is asserted if charging current
is above 20 mA in CDP and DCP modes.
In CDP mode the charging flag is s asserted only if the CDP handshaking between the
portable device and the host is performed before the current is above threshold.
After the current drops below threshold, the output CHARGING is deasserted. The host
system can then disable the high power DC-DC converter and thus reduce the power
consumption. This is crucial when the host is battery supplied.
• An enable input (EN) to enable/disable the device.
The device is offered in a small, RoHS compliant VFQFPN 16L (3 x 3 x 0.8 mm) package
with an exposed pad for effective cooling.
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