LT1085RH–LCC4
MILITARY VERSION
MECHANICAL DATA
Dimensions in mm (inches)
CERAMIC SURFACE MOUNT
LOW DROPOUT POSITIVE
ADJUSTABLE VOLTAGE REGULATOR
FOR SPACE APPLICATION
FEATURES
• Up to 100K Rad Dose Capability
• Ceramic Surface Mount Hermetic Package
• Low Dropout Performance
• Output Current 3A
• Line Regulation 0.015% / V Typical.
• Load Regulation 0.1% Typical.
• Full Temperature Range (–55 to +150°C)
BLOCK DIAGRAM
V
IN
1.27 (0.050)
1.07 (0.040)
9.14 (0.360)
8.64 (0.340)
12 13 14 15 16
1.39 (0.055)
1.02 (0.040)
≈
2.16 (0.085)
11
7.62 (0.300)
7.12 (0.280)
17
18
1
2
0.76 (0.030)
0.51 (0.020)
10
9
8
7
6
5
4
3
1.65 (0.065)
1.40 (0.055)
0.33 (0.013)
Rad.
0.08 (0.003)
1.39 (0.055)
1.15 (0.045)
0.43 (0.017)
0.18 (0.007 Rad.
THERMAL
LIMIT
LCC4
Pads 5,4 = adjust
Pads 6,7,8,9,10,11,13 = Vin
Pads 1,2,15,16,17,18 = Vout
V
ADJ
V
OUT
ABSOLUTE MAXIMUM RATINGS
V
I-O
P
D
V
IN
T
J
T
STG
Input–Output Differential Voltage
Power Dissipation
Operating Input Voltage
Operating Junction Temperature Range
Storage Temperature Range
Thermal Resistance (junction to case)
(T
case
= 25°C unless otherwise stated)
35V
Internally limited
25V
Control
Power
–55 to 150°C
–55 to 200°C
–65 to 150°C
13°C/W
q
JC
* Although the devices’ maximum operating voltage is limited to 25V the devices are guaranteed to withstand transient
input voltages up to 30V. For input voltages greater than the maximum operating input voltage, some degradation of
specifications will occur.
Semelab plc.
Telephone +44(0)1455 556565. Fax +44(0)1455 552612.
Website:
http://www.semelab.co.uk
E-mail:
sales@semelab.co.uk
Prelim. 7/99
LT1085RH–LCC4
MILITARY VERSION
DESCRIPTION
The LT1085 is designed to provide 3A with higher efficiency than currently available devices. All internal circuitry is
designed to operate down to 1V input to output differential and the dropout voltage is fully specified as a function of load
current. Dropout is guaranteed at a maximum of 1.5V at maximum output current, decreasing at lower load currents. On-
chip trimming adjusts the reference output voltage to 1%. Current limit is also trimmed, minimising the stress on both the
regulator and power source circuitry under overload conditions.
ELECTRICAL CHARACTERISTICS
Parameter
V
REF
REG
(LINE)
Reference Voltage
Line Regulation
(T
J
= 25°C unless otherwise stated)
Test Conditions
V
IN
– V
OUT
= 1.5 to 15
V
IN
– V
OUT
= 1.5 to 15V
I
LOAD
= 10mA
V
IN
– V
OUT
= 3V
I
O
= 10mA to 3A
T
J
= –55 to 150°C
T
J
= –55 to 150°C
T
J
= –55 to 150°C
TJ = –55 to 150°C
TJ = –55 to 150°C
TA = 25°C
VIN – VOUT = 3V
CADJ = 25
m
F
T
J
= –55 to 150°C
I
O
= 10mA to 3A
T
J
= –55 to 150°C
Min.
1.225
Typ.
1.25
0.015
0.035
0.1
0.2
1.3
Max. Unit
1.270
0.2
0.5
0.3
0.4
1.5
V
%
%
V
A
10
0.02
mA
%/W
dB
120
5
REG
(LOAD)
Load Regulation
See notes 1,2
V
D
Dropout Voltage
See note 3
I
CL
IQ
Current Limit
Quiescent Current
Minimum Load Current 4
REG(THERM) Thermal Regulation
RA
IPIN
Ripple Rejection
Adjust Pin Current
Adjust Pin Current Change
Temperature Stability
Long Term Stability
VN
RMS Output Noise
D
V
REF
= 1%
I
OUT
= 3A
V
IN
– V
OUT
= 5V
V
IN
– V
OUT
= 25V
V
IN
– V
OUT
= 5V
TP = 30ms
f = 120Hz
IO = 3A
3.2
0.2
4
0.5
5
0.004
60
75
55
0.2
0.5
D
IPIN
TS
TJ = –55 to 150°C
VIN – VOUT = 1.5 to 15V
IO = 10mA to 3A
TJ = –55 to 150°C
TJ = –55 to 150°C
TA = 125°C
f = 10Hz to 10kHz
T = 1000 Hrs
TA = 25°C
m
A
m
A
%
%
%
0.3
0.003
1
Notes:
1.Load and line regulation are measured at a constant junction temperature by low duty cycle pulse testing.
2.Power dissipation is determined by the input - output differential and the output current. Guaranteed maximum power
2
dissipation will not be available over the full input - output voltage range.
3.Dropout voltage is specified over the full output current range of the device.
Semelab plc.
Telephone +44(0)1455 556565. Fax +44(0)1455 552612.
Website:
http://www.semelab.co.uk
E-mail:
sales@semelab.co.uk
Prelim. 7/99