Electronic Components Datasheet Search
TPS254900A-Q1 Datasheet(PDF) 24 Page - Texas Instruments
to check the latest version.
TI1 [Texas Instruments]
TPS254900A-Q1 Datasheet(HTML) 24 Page - Texas Instruments
/ 39 page
Copyright © 2016, Texas Instruments Incorporated
SLUSCU5A – NOVEMBER 2017 – REVISED JANUARY 2018
Product Folder Links: TPS254900A-Q1
Submit Documentation Feedback
Copyright © 2017–2018, Texas Instruments Incorporated
BC1.2 defines a charging port as a downstream-facing USB port that provides power for charging portable
equipment. Under this definition, CDP and DCP are defined as charging ports.
Table 4 lists the difference between these port types.
Table 4. Operating Modes Table
SUPPORTS USB 2.0 COMMUNICATION
MAXIMUM ALLOWABLE CURRENT
DRAWN BY PORTABLE EQUIPMENT (A)
SDP (USB 2.0)
SDP (USB 3.0)
8.4.3 Standard Downstream Port (SDP) Mode — USB 2.0 and USB 3.0
An SDP is a traditional USB port that follows the USB 2.0 or USB 3.0 protocol. An SDP supplies a minimum of
500 mA per port for USB 2.0 and 900 mA per port for USB 3.0. USB 2.0 and USB 3.0 communication is
supported, and the host controller must be active to allow charging.
8.4.4 Charging Downstream Port (CDP) Mode
A CDP is a USB port that follows the USB BC1.2 specification and supplies a minimum of 1.5 A per port. A CDP
provides power and meets the USB 2.0 requirements for device enumeration. USB 2.0 communication is
supported, and the host controller must be active to allow charging. The difference between CDP and SDP is the
host-charge handshaking logic that identifies this port as a CDP. A CDP is identifiable by a compliant BC1.2
client device and allows for additional current draw by the client device.
The CDP handshaking process occurs in two steps. During the first step, the portable equipment outputs a
nominal 0.6-V output on the D+ line and reads the voltage input on the D– line. The portable device detects the
connection to an SDP if the voltage is less than the nominal data-detect voltage of 0.3 V. The portable device
detects the connection to a CDP if the D– voltage is greater than the nominal data-detect voltage of 0.3 V and
optionally less than 0.8 V.
The second step is necessary for portable equipment to determine whether the equipment is connected to a CDP
or a DCP. The portable device outputs a nominal 0.6-V output on the D– line and reads the voltage input on the
D+ line. The portable device concludes the equipment is connected to a CDP if the data line being read remains
less than the nominal data detects voltage of 0.3 V. The portable device concludes it is connected to a DCP if
the data line being read is greater than the nominal data-detect voltage of 0.3 V.
The TPS254900A-Q1 device integrates CDP detection protocol, used at a downstream port as the CDP
controller to support CDP portable-device fast charge up to 1.5 A.
8.4.5 Client Mode
The TPS254900A-Q1 device integrates client mode as shown in Figure 42. The internal power switch is OFF to
block current flow from OUT to IN, and the signal switches are ON. This mode can be used for software
upgrades from the USB port.
Figure 42. Client-Mode Equivalent Circuit
Does ALLDATASHEET help your business so far?
[ DONATE ]
All Rights Reserved©
| English :
| Chinese :
| German :
| Japanese :
| Korean :
| Spanish :
| French :
| Italian :
| Polish :
| Vietnamese :