Datasheet

OUT(av)

0 A

ON OFF

UDG-12108

SC_TURN_OFF

OS_DEG

–

2 V 2.7 V 1.2 V

GND

D+

D–

BUS

USB Connector

5 V 8

OUT

GND

Divider 2

S1, S2: ON

S3, S4: OFF

Short Mode

S4: ON

S1, S2, S3: OFF

1.2 V on DP and DM

S3, S4: ON

S1, S2: OFF

TPS2511

UDG-12099

TPS2511

SLUSB18 –JUNE 2012

www.ti.com

Figure 28. TPS2511 DCP Auto-Detect Functional Diagram

Overcurrent Protection

During an overload condition, the TPS2511 maintains a constant output current and reduces the output voltage

accordingly. If the output voltage falls below 3.8 V for 16 ms, the TPS2511 turns off the output for a period of 12

seconds as shown in Figure 29. This operation is referred to as hiccup mode. The device stays in hiccup mode

(power cycling) until the overload condition is removed. Therefore the average output current is significantly

reduced to greatly improve the thermal stress of the device while the OUT pin is shorted.

Figure 29. OUT Pin Short-Circuit Current in Hiccup Mode

Two possible overload conditions can occur. In the first condition, the output has been shorted before the device

is enabled or before the voltage of IN has been applied. The TPS2511 senses the short and immediately

switches into hiccup mode of constant-current limiting. In the second condition, a short or an overload occurs

while the device is enabled. At the instant the overload occurs, high currents may flow for several microseconds

before the current-limit circuit can react. The device operates in constant-current mode for a period of 16 ms after

the current-limit circuit has responded, then switches into hiccup mode (power cycling).

Product Folder Link(s) :TPS2511