TPS79101, TPS79118

TPS79133,TPS79147

SLVS325C − MARCH 2001 − REVISED MAY 2002

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12

OUTPUT VOLTAGE

PROGRAMMING GUIDE

VO

VI

OUT

FB

R1

R2

GND

EN

IN

TPS79101

1

µF

BYPASS

0.01

µF

1

µF

C1

22 pF

15 pF

15 pF

OUTPUT

VOLTAGE

R1

R2

2.5 V

3.3 V

3.6 V

C1

31.6 k

Ω

51 k

Ω

59 k

Ω

30.1 k

Ω

30.1 k

Ω

30.1 k

Ω

≤ 0.7 V

≥ 2 V

Figure 33. TPS79101 Adjustable LDO Regulator Programming

REGULATOR PROTECTION

The TPS791xx PMOS-pass transistor has a built-in back diode that conducts reverse current when the input

voltage drops below the output voltage (e.g., during power down). Current is conducted from the output to the

input and is not internally limited. If extended reverse voltage operation is anticipated, external limiting might

be appropriate.

The TPS791xx features internal current limiting and thermal protection. During normal operation, the TPS791xx

limits output current to approximately 400 mA. 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 or the absolute maximum

voltage ratings of the device. If the temperature of the device exceeds approximately 165

°C, thermal-protection

circuitry shuts it down. Once the device has cooled down to below approximately 140

°C, regulator operation

resumes.