TPS70102PWPR datasheet(33/42 Pages) TI

33 / 42 page

OUTPUTVOLTAGE

PROGRAMMINGGUIDE

OUT

GND

<0.7V

>2.0 V

TPS70102

0.1 mF

OUTPUT

VOLTAGE

2.5V

3.3V

3.6V

UNIT

31.6

51.1

59.0

30.1

D(max)

J max

*TA

+ VI*VO

TPS70145, TPS70148

TPS70151, TPS70158

TPS70102

www.ti.com

SLVS222I – DECEMBER 1999 – REVISED AUGUST 2010

Figure 50. TPS70102 Adjustable LDO Regulator Programming

Regulator Protection

Both TPS701xx PMOS-pass transistors have built-in back diodes that conduct 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 TPS701xx also features internal current limiting and thermal protection. During normal operation, the

TPS701xx regulator 1 limits output current to approximately 1.6A (typ) and regulator 2 limits output current to

approximately 750mA (typ). 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.

Power Dissipation and Junction Temperature

Specified regulator operation is assured to a junction temperature of +125°C; the maximum junction temperature

should be restricted to +125°C under normal operating conditions. This restriction limits the power dissipation the

regulator can handle in any given application. To ensure the junction temperature is within acceptable limits,

calculate the maximum allowable dissipation, PD(max), and the actual dissipation, PD, which must be less than or

equal to PD(max).

The maximum-power-dissipation limit is determined using Equation 2:

(2)

where:

•

TJmax is the maximum allowable junction temperature

•

RqJA is the thermal resistance junction-to-ambient for the package; that is, 32.6°C/W for the 20-terminal PWP

with no airflow

•

TA is the ambient temperature

The regulator dissipation is calculated using Equation 3:

(3)

Power dissipation resulting from quiescent current is negligible. Excessive power dissipation will trigger the

thermal protection circuit.

Submit Documentation Feedback

TPS70102PWPR Datasheet(PDF) 33 Page - Texas Instruments

TPS70102PWPR Datasheet(HTML) 33 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

Datasheet Download

Link URL