LT1085GMD
LT1085IGDII
LT1085SMD
3 AMP POSITIVE
VOLTAGE REGULATOR
FEATURES
• Low Dropout Performance
INPUT
• Fixed or Adjustable Voltages
SAFE AREA
PROTECTION
• 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.
LIMIT
CURRENT
LIMITING
AMPLIFIER
OUTPUT
SENSE
• Available in Hermetically Sealed TO–3, SMD1 and
TO–257 (isolated & non-isolated) Packages.
T HERM AL
OVERLO AD
• Military Temperature Range (–55 to +150°C)
VOLTAGE
REGULATION
AMPLIFIER
(1)
DEVICE
PACKAGE
VRE F
ADJUST
LT1085K–XX
LT1085G–XX
LT1085IG–XX
LT1085SMD–XX
TO–3
TO–257
Isolated TO–257
SMD1
DESCRIPTION
Note
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.
1) –XX = Voltage Option: 3.3, 5 or 12
–XX = Left blank for Adjustable Option.
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.
ABSOLUTE MAXIMUM RATINGS (T
= 25°C unless otherwise stated)
case
V
Input – Output Voltage Differential
35V
IN
P
Power Dissipation
Internally limited *
D
R
R
R
Thermal Resistance Junction To Case
TO–3
TO–3
Control
Power
0.93°C / W
3.0°C / W
JC
JC
JC
Thermal Resistance Junction To Case
Thermal Resistance Junction To Case
SMD1
SMD1
Control
Power
0.79°C / W
4.0°C / W
TO–257
TO–257
Control
Power
0.79°C / W
4.0°C / W
T
Operating Junction Temperature Range
Control
Power
–55 to 150°C
–55 to 200°C
J
T
T
Storage Temperature Range
Lead Temperature (for 10 sec.)
–65 to 150°C
300°C
STG
LEAD
* These ratings are only applicable for power dissipations of 30 Watts over a limited range of VIN – VOUT
.
Semelab plc. Telephone +44(0)1455 556565. Fax +44(0)1455 552612.
Prelim. 7/00
E-mail: sales@semelab.co.uk
Website: http://www.semelab.co.uk