Note 1: Output or reference voltage temperature coefficients is defined as the worst case voltage change divided by

the total temperature range.

shutdown

≤0.8 V.

Note 3: Regulations is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes

in output voltage due to heating effects are covered under the specification for thermal regulation.

guaranteed by design to 0.2%. See typical performance characteristics for line regulation verse temperature and load

current.

Note 5: Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV below its

nominal value measured at 1V differential. At very low values of programmed output voltage, the minimum input

supply voltage of 2V(2.3V over temperature) must be taken into account.

Note 7: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the

total temperature range.

Note 8: Comparator thresholds are expressed in terms of a voltage differential at the feedback terminal below the

error output is guaranteed to go low when the output drops by 95mVx5V/1.235V=384mV. Thresholds remain constant

guaranteed.

LND2950 / LND2951

BLOCK DIAGRAM AND TYPICAL APPLICATIONS

APPLICATION HINTS

External Capacitors

A 1.0

µF (or greater ) capacitor is required between the output and the ground for stability at output

voltages of 5V or more. At lower output voltages, more capacitance is required. 2.2

µF or more is

recommended for 3 V and 3.3 V versions.

Programming the Output Voltage

The LND2951 may be pin-strapped for the nominal fixed output voltage. Alternatively it may be

programmed for any output voltage between 1.24 V and 29 V depending upon the requirements.

• Linear Dimensions, Inc. • 445 East Ohio Street, Chicago IL 60611 USA • tel 312.321.1810 • fax 312.321.1830 • www.lineardimensions.com •

Vout

See

Application

Hints

OUTPUT

I

<= 100mA

L

GROUND

INPUT

+

-

ERROR

AMPLIFIER

+

+

1.23 V

Reference

Unregulated DC

+

Vout

See

Application

Hints

SENSE

I

<= 100mA

L

GROUND

INPUT

+

-

ERROR

AMPLIFIER

+

FEEDBACK

+

-

60 mV

+

+

1.23 V

Reference

II

Error detection Comparator

OUTPUT

XX VTAP

ERROR

SHUTDOWN

From

CMOS

or

TTL

To

CMOS

or

TTL

Unregulated DC

330k

Ω

1

2

6

5

4

8

7

3

60k

+