Datasheet
R
1
+
ǒ
V
OUT
V
REF
*1
Ǔ
R
2
(2)
IN
EN
FB/NC
OUT
RESET
RESET Output
GND
+
C
OUT
10 Fm
V
OUT
V
IN
250kW
TPS767D301
0.1 Fm
R
2
R
1
>2.7V
<0.5V
OUTPUTVOLTAGE
PROGRAMMINGGUIDE
2.5V
3.3V
3.6V
4.75V
33.2
53.6
61.9
90.8
30.1
30.1
30.1
30.1
R
2
R
1
OUTPUT
VOLTAGE UNIT
kW
kW
kW
kW
RESET INDICATOR
REGULATOR PROTECTION
TPS767D3xx
SLVS209H – JULY 1999 – REVISED AUGUST 2008 .........................................................................................................................................................
www.ti.com
The recommended design procedure is to choose R
2
= 30.1 k Ω to set the divider current at 40 µ A and then
calculate R
1
using:
Figure 26. TPS767D301 Adjustable LDO Regulator Programming
The TPS767D3xx features a RESET output that can be used to monitor the status of the regulator. The internal
comparator monitors the output voltage: when the output drops to 95% (typical) of its regulated value, the
RESET output transistor turns on, taking the signal low. The open-drain output requires a pullup resistor. If not
used, it can be left floating. RESET can be used to drive power-on reset circuitry or as a low-battery indicator.
The TPS767D3xx PMOS-pass transistor has a built-in back-gate diode that safely conducts reverse currents
when the input voltage drops below the output voltage (for example, during power-down). Current is conducted
from the output to the input and is not internally limited. When extended reverse voltage is anticipated, external
limiting may be appropriate.
The TPS767D3xx also features internal current limiting and thermal protection. During normal operation, the
TPS767D3xx limits output current to approximately 1.7A. When current limiting engages, the output voltage
scales back linearly until the overcurrent condition ends. While current limiting is designed to prevent gross
device failure, care should be taken not to exceed the power dissipation ratings of the package. If the
temperature of the device exceeds +150 ° C (typ), thermal-protection circuitry shuts it down. Once the device has
cooled below +130 ° C (typ), regulator operation resumes.
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