TPS76030, TPS76032, TPS76033, TPS76038, TPS76050

LOW-POWER 50-mA LOW-DROPOUT LINEAR REGULATORS

SLVS144B –JULY 1998 – REVISED FEBRUARY 1999

9

POST OFFICE BOX 655303

APPLICATION INFORMATION

1

3

5

TPS760xx

IN

EN

OUT

2

CI = 1 µF

Co = 2.2 µF

GND

Figure 17. TPS760xx Typical Application

over current protection

The over current protection circuit forces the TPS760xx into a constant current output mode when the load is

excessive or the output is shorted to ground. Normal operation resumes when the fault condition is removed.

An overload or short circuit may also activate the over temperature protection if the fault condition persists.

over temperature protection

The thermal protection system shuts the TPS760xx down when the junction temperature exceeds 160

_C. The

device recovers and operates normally when the temperature drops below 150

_C.

input capacitor

A 0.047

µF or larger ceramic decoupling capacitor with short leads connected between IN and GND is

recommended. The decoupling capacitor may be omitted if there is a 1

µF or larger electrolytic capacitor

connected between IN and GND and located reasonably close to the TPS760xx. However, the small ceramic

device is desirable even when the larger capacitor is present, if there is a lot of high frequency noise present

in the system.

output capacitor

Like all low dropout regulators, the TPS760xx requires an output capacitor connected between OUT and GND

to stabilize the internal control loop. The minimum recommended capacitance value is 2.2

µF and the ESR

(equivalent series resistance) must be between 0.1

Ω and 20 Ω. Capacitor values of 2.5-µF or larger are

acceptable, provided the ESR is less than 20

Ω. Solid tantalum electrolytic, aluminum electrolytic, and multilayer

ceramic capacitors are all suitable, provided they meet the requirements described above. Most of the

commercially available 2.2-

µF surface-mount solid-tantalum capacitors, including devices from Sprague,

Kemet, and Nichicon, meet the ESR requirements stated above. Multilayer ceramic capacitors should have

minimum values of 2.5

µF over the full operating temperature range of the equipment.

enable (EN)

A logic zero on the enable input shuts the TPS760xx off and reduces the supply current to less than 1

the enable input high causes normal operation to resume. If the enable feature is not used, EN should be

connected to IN to keep the regulator on all of the time. The EN input must not be left floating.