Website: http://www.semelab.co.uk

Prelim. 7/00

LT1085SMD

PACKAGE

LT1085K–XX

TO–3

LT1085G–XX

TO–257

LT1085IG–XX

Isolated TO–257

LT1085SMD–XX

SMD1

DESCRIPTION

The LT1085 voltage regulators are monolithic inte-

grated circuits designed for use in applications

requiring a well regulated positive output voltage

with

low

input-output

differential

voltage.

Features include full power usage of up to 3A load current, internal current limiting and thermal shutdown. Safe area

protection on the die is also included, providing protection of the series pass Darlington transistor under most conditions.

The hermetically sealed TO–3 packages are utilised for high reliablitiy and low thermal resistance, whilst the SMD1

package is designed for surface mount applications.

Note

1) –XX = Voltage Option: 3.3, 5 or 12

–XX = Left blank for Adjustable Option.

3 AMP POSITIVE

VOLTAGE REGULATOR

Input – Output Voltage Differential

Power Dissipation

Thermal Resistance Junction To Case

TO–3

Control

TO–3

Power

Thermal Resistance Junction To Case

SMD1

Control

SMD1

Power

Thermal Resistance Junction To Case

TO–257

Control

TO–257

Power

Operating Junction Temperature Range

Control

Power

Storage Temperature Range

35V

Internally limited *

0.93°C / W

3.0°C / W

0.79°C / W

4.0°C / W

0.79°C / W

4.0°C / W

–55 to 150°C

–55 to 200°C

–65 to 150°C

300°C

FEATURES

• Low Dropout Performance

• Fixed or Adjustable Voltages

• Fixed Output Voltages of 3.3V, 5V & 12V

• Adjustable Output Voltage Range From 1.2V

• Line Regulation 0.015% / V Typical.

• Load Regulation 0.01% Typical.

• Available in Hermetically Sealed TO–3, SMD1 and

TO–257 (isolated & non-isolated) Packages.

• Military Temperature Range (–55 to +150°C)

INPUT

SAFE AREA

PROTECT ION

TH E R M AL

O V ER L O AD

CU RR EN T

LIMITING

AMPLIFIER

VOL T AGE

REGUL ATION

AMPLIFIER

OU TPUT

ADJUST

LIMIT

SEN SE

V

RE F