LM185-1.2/
LM285-1.2/LM385-1.2
1
FEATURES
DESCRIPTIO
U
APPLICATIO S
U
TYPICAL APPLICATIO
U
■
Portable Meter References
■
Portable Test Instruments
■
Battery Operated Systems
■
Current Loop Instrumentation
■
10µA to 20mA Operating Range
■
Guaranteed
1% Initial Voltage Tolerance
■
Guaranteed
1Ω Dynamic Impedance
■
Very Low Power Consumption
Micropower Voltage
Reference
Reverse Voltage Change with Current
The LM185-1.2 is a two terminal band gap reference diode
that has been designed for applications which require
precision performance with micropower operation. The
device provides guaranteed operating specifications at
currents as low as 10µA. The nominal voltage is 1.235V
with both 1% and 2% tolerances available. Some addi-
tional features are: maximum dynamic impedance of 1Ω,
low noise and excellent stability over time and tempera-
ture. Advanced design, processing and testing techniques
make Linear’s LM185-1.2 a superior choice over previous
designs. A micropower 5V reference application is shown
below. For guaranteed TC, micropower references, see the
LT1034 data sheet.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Micropower 5V Reference
–
+
185/285/385 TA01a
V
+
V
–
LM385-1.2
LM334
LT1494
3
2
7
6
4
R
5.6k
150pF 3.01M
1%
1M
1%
V
IN
7V TO 15V
5V
REVERSE CURRENT (mA)
OUTPUT VOLTAGE CHANGE (mV)
10
8
6
4
2
0
–2
0.01 1 10 100
185/285/385 TA01b
0.1
T
A
= 25°C
LM185-1.2/
LM285-1.2/LM385-1.2
2
ABSOLUTE AXI U RATI GS
W
WW
U
Operating Temperature Range
LM185-1.2(OBSOLETE) ............... –55°C to 125°C
LM285-1.2 ..........................................–40°C to 85°C
LM385-1.2 .............................................. 0°C to 70°C
ORDER PART
NUMBER
T
JMAX
= 150°C, θ
JA
= 160°C/W
LM185H-1.2
LM285H-1.2
LM385H-1.2
LM385BH-1.2
PACKAGE/ORDER I FOR ATIO
UUW
Consult LTC Marketing for parts specified with wider operating temperature ranges.
Storage Temperature Range ................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)..................300°C
Reverse Breakdown Current ................................. 30mA
Forward Current ................................................... 10mA
OBSOLETE PACKAGE
(NOTE 3)
T
JMAX
= 150°C,
θ
JA
= 440°C/W, θ
JC
= 80°C/W
(NOTE 3)
TOP VIEW
NC
NC
NC
NC
S8 PACKAGE
8-LEAD PLASTIC SO
1
2
3
4
8
7
6
5NC
(DO
NOT USE)
BOTTOM VIEW
Z PACKAGE
3-LEAD PLASTIC TO-92
BOTTOM VIEW
H PACKAGE
2-LEAD TO-46 METAL CAN
12
LM385BS8-1.2
LM385S8-1.2
ORDER PART
NUMBER
3851
3851B
S8 PART
MARKING
T
JMAX
= 150°C, θ
JA
= 190°C/W
ORDER PART
NUMBER
LM285Z-1.2
LM385Z-1.2
LM385BZ-1.2
Consider the S8 or Z Packages for Alternate Source
LM185-1.2/
LM285-1.2/LM385-1.2
3
ELECTRICAL CHARACTERISTICS
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Selected devices with guaranteed maximum temperature
coefficient are available upon request.
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. For the LM185-1.2 TMIN = –55°C and TMAX = 125°C. For LM285-1.2
TMIN = –40°C and TMAX = 85°C.For LM385-1.2 TMIN = 0°C and TMAX = 70°C. For MIL-STD components, please refer to LTC883C data
sheet for test listing and parameters.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX UNITS
V
Z
Reverse Breakdown Voltage T
A
= 25°C, I
MIN
≤ I
R
≤ 20mA
LM185-1.2 1.223 1.235 1.247 V
LM385-1.2 1.205 1.235 1.260 V
LM385B-1.2 (Note 3) 1.223 1.235 1.247 V
∆V
Z
Average Temperature Coefficient I
MIN
≤ I
R
≤ 20mA (Notes 2, 3) 20 20 ppm/°C
∆Temp
I
MIN
Minimum Operating Current T
MIN
␣≤␣T
A
≤␣T
MAX
●810 8 15 µA
∆V
Z
Reverse Breakdown Voltage I
MIN
≤ I
R
≤ 1mA
∆I
R
Change with Current T
A
= 25°C11mV
T
MIN
≤ T
A
≤ T
MAX
●1.5 1.5 mV
1mA ≤ I
R
≤ 20mA
T
A
= 25°C1010mV
T
MIN
≤ T
A
≤ T
MAX
●20 25 mV
r
Z
Reverse Dynamic Impedance I
R
= 100µA
T
A
=25°C 0.2 0.6 0.4 1.0 Ω
T
MIN
≤ T
A
≤ T
MAX
●1.5 1.5 Ω
e
n
Wideband Noise (RMS) I
R
= 100µA, 10Hz ≤ f ≤ 10kHz 60 60 µV
∆V
Z
Long Term Stability I
R
= 100µA, T
A
= 25°C ± 0.1°C 20 20 ppm/kHr
∆Time
LM385-1.2/LM385B-1.2
Note 3: For applications requiring low initial tolerance guaranteed over
temperature consult the LT1004 data sheet.
LM185-1.2/LM285-1.2
LM185-1.2/
LM285-1.2/LM385-1.2
4
Reverse Characteristics Foward Characteristics
Temperature Drift Reverse Dynamic Impedance Reverse Dynamic Impedance
Noise Voltage Filtered Output Noise Response Time
TYPICAL PERFOR A CE CHARACTERISTICS
UW
REVERSE VOLTAGE (V)
0
REVERSE CURRENT (µA)
100
10
1
0.1 0.6 1.0
185/285/385 G01
0.2 0.4 0.8 1.2 1.4
–55°C TO 125°C
FORWARD CURRENT (mA)
FORWARD VOLTAGE (V)
1.2
0.8
0.4
0
0.01 1 10 100
185/285/385 G02
0.1
TA = 25°C
TEMPERATURE (°C)
–55
REVERSE VOLTAGE (V)
–15 25 45 125
185/285/385 G03
–35 5 65 85 105
1.245
1.240
1.235
1.230
REVERSE CURRENT (mA)
DYNAMIC IMPEDANCE (Ω)
100
10
1
0.1
0.01 1 10 100
185/285/385 G04
0.1
–55°C TO 125°C
f = 25Hz
FREQUENCY (Hz)
10
DYNAMIC IMPEDANCE (Ω)
10k
1k
100
10
1
0.1 100k
185/285/385 G05
100 1k 10k 1M
T
A
= 25°C
I
R
= 100µA
NOISE (nV/√Hz)
700
600
500
400
300
200
100
0
FREQUENCY (Hz)
10 1k 10k 100k
185/285/385 G06
100
IR = 100µA
INTEGRATED NOISE (µV
RMS
)
70
60
50
40
30
20
10
0
CUTOFF FREQUENCY (Hz)
1k 10k 100k
185/285/385 G07
100
R
C
100µA
I
R
= 100µA
RC LOW PASS
TIME (µs)
VOLTAGE (V)
2.0
1.5
1.0
0.5
0
5
0
–5
185/285/385 G08
–100 0100 200 300 400 500
INPUT
OUTPUT
V
IN
36k V
OUT
LM185-1.2/
LM285-1.2/LM385-1.2
5
W
SCHE ATIC DIAGRA
W
185/285/385 SD
+
–
Q1
Q2 Q5
Q3
Q4
Q7
Q12
Q11
Q13
Q10
Q6 Q14Q8
Q9
20pF 20pF
7.5k
100k
200k
50k
300k
500Ω60k
600k
LM185-1.2/
LM285-1.2/LM385-1.2
6
PACKAGE DESCRIPTIO
U
0.050
(1.27)
BSC
0.060 ± 0.005
(1.524± 0.127)
DIA
0.90
(2.286)
NOM
0.180 ± 0.005
(4.572 ± 0.127)
0.180 ± 0.005
(4.572 ± 0.127)
0.500
(12.70)
MIN
0.050
(1.270)
MAX
UNCONTROLLED
LEAD DIMENSION
0.016 ± 0.003
(0.406 ± 0.076)
5°
NOM
0.015 ± 0.002
(0.381 ± 0.051)
0.060 ± 0.010
(1.524 ± 0.254)
10° NOM
0.140 ± 0.010
(3.556 ± 0.127)
Z3 (TO-92) 0401
0.098 +016/–0.04
(2.5 +0.4/–0.1)
2 PLCS
TO-92 TAPE AND REEL
REFER TO TAPE AND REEL SECTION OF
LTC DATA BOOK FOR ADDITIONAL INFORMATION
0.016 – 0.021**
(0.406 – 0.533)
DIA
0.025
(0.635)
MAX
0.085 – 0.105
(2.159 – 2.667)
0.500
(12.700)
MIN
0.178 – 0.195
(4.521 – 4.953)
0.209 – 0.219
(5.309 – 5.537)
0.100
(2.540)
TYP
45°
H02/03(TO-46) 1098
0.050
(1.270)
TYP
0.050
(1.270)
TYP
0.028 – 0.048
(0.711 – 1.219)
0.036 – 0.046
(0.914 – 1.168)
FOR 3-LEAD PACKAGE ONLY
REFERENCE
PLANE *
LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE
AND 0.045" BELOW THE REFERENCE PLANE
FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS 0.016 – 0.024
(0.406 – 0.610)
*
**
PIN 1
H Package
2-Lead and 3-Lead TO-46 Metal Can
(Reference LTC DWG # 05-08-1340)
Z Package
3-Lead Plastic TO-92 (Similar to TO-226)
(Reference LTC DWG # 05-08-1410)
OBSOLETE PACKAGE
LM185-1.2/
LM285-1.2/LM385-1.2
7
PACKAGE DESCRIPTIO
U
0.016 – 0.050
(0.406 – 1.270)
0.010 – 0.020
(0.254 – 0.508)× 45°
0°– 8° TYP
0.008 – 0.010
(0.203 – 0.254)
SO8 1298
0.053 – 0.069
(1.346 – 1.752)
0.014 – 0.019
(0.355 – 0.483)
TYP
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC
1234
0.150 – 0.157**
(3.810 – 3.988)
8765
0.189 – 0.197*
(4.801 – 5.004)
0.228 – 0.244
(5.791 – 6.197)
DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
*
**
S8 Package
8-Lead Plastic Small Outline (Narrow .150 Inch)
(Reference LTC DWG # 05-08-1610)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
LM185-1.2/
LM285-1.2/LM385-1.2
8
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 1985
18512fa LT/CP 0901 1.5K REV A • PRINTED IN USA
RELATED PARTS
PART NUMBER DESCRIPTION COMMENTS
LT1004-1.2 Micropower Shunt Reference 0.3% Initial Accuracy
LT1034 1.2V Micropower Shunt Reference 40ppm/°C Max Temperature Coefficient
Micropower Reference for 9V Battery 1.2V Reference from 1.5V Battery
185/285/385 TA02
9V
510k
LM385-1.2
1.23V
185/285/385 TA03
1.5V
3k
LM385-1.2
1.23V
TYPICAL APPLICATIO S
U
