Datasheet

0
0.02
0.04
0.06
0.08
0.1
0.12
0 200 400 600 800 1000 1200 1400 1600 1800
I - Output Current - mA
O
Dropout Voltage - V
Operation www.ti.com
Figure 4. Dropout Voltage, V
DO
, measurement of TPS74001DPTEVM-713
for V
BIAS
= 5.0V, V
OUT
= 1.5V
4.4 Enable / Shutdown (Fixed Voltage Version Only – TPS74012DPT)
The EN pin is active high and enables the regulator. When V
EN
is above 1.1V, the regulator turns on.
When V
EN
is below 0.4V, the regulator turns off. The enable circuitry has hysteresis and deglitching to help
avoid on/off cycling as a result of small glitches in the V
EN
signal. V
EN
threshold is typically 0.8V but varies
slightly with temperature and process variations. See the TPS740xx datasheet for more information.
4.5 Internal Current Limit
TPS740xxDPT features an internal current limit protection circuitry that is designed to protect against
overload conditions. The current limit responds in approximately 10µs to reduce the current during a
short-circuit fault. The current limit circuitry will allow up to a maximum of 4.0A before clamping the output
current. The resulting V
OUT
will be 80% of V
OUT
nominal. See the TPS740xx datasheet for more
information.
4.6 Thermal Protection
TPS740xxDPT comes with a thermal protection circuit that disables the output of the IC when the junction
temperature rises to approximately 160°C. When the junction temperature cools down to approximately
140°C, the output circuitry is once again enabled. The thermal protection circuit may cycle on and off
depending on the power dissipation, thermal resistance, and ambient temperature of the EVM. See the
TPS740xx datasheet for more information.
6
TPS740xxDPTEVM-713 Evaluation Module SLVU476– June 2011
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