LINER LM185-2.5

LM185-2.5/
LM285-2.5/LM385-2.5
Micropower Voltage
Reference
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DESCRIPTIO
FEATURES
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20µA to 20mA Operating Range
Guaranteed 1% Initial Voltage Tolerance
Guaranteed 1Ω Dynamic Impedance
Very Low Power Consumption
The LM185-2.5 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 operation specifications at currents as low as 20µA. The nominal voltage is
2.5V with both 1% and 2% tolerances available. Some
additional features are: maximum dynamic impedance of
1Ω, low noise and excellent stability over time and temperature. The advanced design, processing and testing
techniques make Linear’s LM185-2.5 a superior choice
over previous designs. A circuit for cold junction compensation of a thermocouple is shown below.
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APPLICATI
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S
Portable Meter References
Portable Test Instruments
Battery-Operated Systems
Panel Meters
Current Loop Instrumentation
For applications requiring guaranteed temperature drift,
see the LT1034 data sheet.
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TYPICAL APPLICATI
Thermocouple Cold Junction Compensator
Reverse Voltage Change
16
VIN
16k
1M
2 MERCURY
CELLS 2.6V
LM334
100k W.W.
ZERO
V–
RSET
2k
LM385-2.5
950Ω
TYPE K
450Ω
+
–
METER
10k ADJUST
FOR 12.17mV
AT 25°C
ACROSS 450Ω
LM185-2.5 TA01
OUTPUT VOLTAGE CHANGE (mV)
IQ ≈ 50µA
–55°C ≤ TA ≤ +125°C
12
8
4
0
–4
0.01
0.1
1
10
REVERSE CURRENT (mA)
100
LM185-2.5 TA02
1
LM185-2.5/
LM285-2.5/LM385-2.5
W W
W
AXI U
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ABSOLUTE
RATI GS
Reverse Breakdown Current ................................ 30mA
Forward Current................................................... 10mA
Operating Temperature Range
LM185-2.5 ..................................... –55°C to 125°C
LM285-2.5 ...................................... – 40°C to 85°C
LM385-2.5 ........................................... 0°C to 70°C
Storage Temperature Range
LM185-2.5 .................................... – 65°C to 150°C
LM285-2.5 .................................... – 65°C to 150°C
LM385-2.5 .................................... – 65°C to 150°C
Lead Temperature (Soldering, 10 sec.)................ 300°C
W
U
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PACKAGE/ORDER I FOR ATIO
TOP VIEW
NC
1
8
NC
2
7
NC
3
6
4
5
S8 PACKAGE
8-LEAD PLASTIC SO
NC
NC
(DO NOT
USE)
LM185-2.5 PO03
ORDER PART
NUMBER
LM285S8-2.5
LM385S8-2.5
LM385BS8-2.5
PART MARKING
2852
3852
3852B
ORDER PART
NUMBER
BOTTOM VIEW
1
LM185H-2.5
LM285H-2.5
LM385H-2.5
LM385BH-2.5
(NOTE 2)
2
H PACKAGE
2-LEAD TO-46 METAL CAN
ELECTRICAL CHARACTERISTICS
LM185-2.5 PO01
PARAMETER
CONDITIONS
VZ
Reverse Breakdown Voltage
TA = 25°C, 20µA ≤ IR ≤ 20mA
LM185-2.5/285-2.5
LM385-2.5
LM385B-2.5 (Note 2)
3
2
LM285Z-2.5
LM385Z-2.5
LM385BZ-2.5
(NOTE 2)
1
Z PACKAGE
3-LEAD TO-92 PLASTIC
LM185-2.5 PO02
LM185-2.5/285-2.5
MIN
TYP
MAX
2.462
2.500
LM385-2.5/385B-2.5
MIN
TYP MAX
Average Temperature Coefficient
20µA ≤ IR ≤ 20mA (Note 2)
IMIN
Minimum Operating Current
TMIN ≤ TA ≤ TMAX
●
∆VZ
∆IR
Reverse Breakdown Voltage
Change With Current
20µA ≤ IR ≤ 1mA
TA = 25°C
TMIN ≤ TA ≤ TMAX
●
1mA ≤ IR ≤ 20mA
TA = 25°C
TMIN ≤ TA ≤ TMAX
●
IR = 100µA (Note 3)
TA = 25°C
TMIN ≤ TA ≤ TMAX
●
20
8
0.2
UNITS
2.538
2.425
2.462
∆VZ
∆Temp
Reverse Dynamic Impedance
BOTTOM VIEW
(See Note 1)
SYMBOL
rZ
ORDER PART
NUMBER
V
V
V
2.500 2.575
2.500 2.538
20
ppm/°C
20
µA
1.0
1.5
2.0
2.5
mV
mV
10
20
20
25
mV
mV
1.0
1.5
Ω
Ω
20
0.6
1.5
8
0.4
en
Wide Band Noise (RMS)
10Hz ≤ f ≤ 10kHz, IR = 100µA
120
120
µV
∆VZ
∆Time
Long Term Stability
TA = 25°C ± 0.1°C, IR = 100µA
20
20
ppm/kHr
The ● denotes specifications which apply over the operating temperature
range.
Note 1: All specifications are for TA = 25°C unless otherwise noted. For
the LM185-2.5 TMIN = – 55°C and TMAX = 125°C. For LM285-2.5, TMIN =
– 40°C and TMAX = 85°C. For LM385-2.5, TMIN = 0°C and TMAX = 70°C.
2
Note 2: For very low initial tolerance, consult LT1004 data sheet. The
LT1004 is a low cost, pin for pin substitution device. For guaranteed
temperature coefficient consult the LT1034-2.5 data sheet.
Note 3: Guaranteed but not tested.
LM185-2.5/
LM285-2.5/LM385-2.5
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TYPICAL PERFOR A CE CHARACTERISTICS
Reverse Characteristics
Forward Characteristics
TA = 25°C
10
1
2.520
REFERENCE VOLTAGE (V)
FORWARD VOLTAGE (V)
–55°C TO 125°C
REVERSE CURRENT (µA)
Temperature Drift
2.525
1.6
100
1.2
0.8
0.4
2.515
2.510
2.505
2.500
2.495
2.490
2.485
0
0.01
0.1
0.5
0
1.0
1.5
2.0
REVERSE VOLTAGE (V)
2.5
3.0
0.1
1
10
FORWARD CURRENT (mA)
Reverse Dynamic Impedance
Noise Voltage
1400
10k
f = 25Hz
–55°C TO 125°C
1
0.1
1
10
REVERSE CURRENT (mA)
1000
100
10
800
600
400
1
0.1
100
1200
1k
NOISE (nV/√Hz)
DYNAMIC IMPEDANCE (Ω)
TA = 25°C
IR = 100µA
10
0.1
0.01
LM185-2.5 • TPC03
Reverse Dynamic Impedance
1000
100
5 25 45 65 85 105 125
TEMPERATURE (°C)
LM185-2.5 • TPC02
LM185-2.5 • TPC01
DYNAMIC IMPEDANCE (Ω)
100
2.480
–55 –35 –15
200
0
10
100
10k
1k
FREQUENCY (Hz)
LM185-2.5 • TPC05
100k
1M
10
LM185-2.5 • TPC05
Filtered Output Noise
100
1k
10k
FREQUENCY (Hz)
100k
LM185-2.5M • TPC06
Response Time
120
100
R
4.0
C
80
3.0
VOLTAGE (V)
INTEGRATED NOISE (µVRMS)
100mA
60
40
RC LOW PASS
20
OUTPUT
2.0
24k
1.0
VIN
VOUT
0
5V
INPUT
0
100
1k
10k
100k
0
0
100
500
TIME (µS)
CUTOFF FREQUENCY (Hz)
LM185-2.5 • TPC07
LM185-2.5 • TPC08
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 representation that the interconnection of circuits as described herein will not infringe on existing patent rights.
3
LM185-2.5/
LM285-2.5/LM385-2.5
W
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SCHE ATIC DIAGRA
TYPICAL APPLICATI
S
+
V+
9V
Q13
7.5k
3.7V ≤ V + ≤ 30V
200k
Q12
Q4
Q3
LM334
220k
Q7
2.7k
20pF
Q11
20pF
Q1
50k
600k
2.5V
500k
Q10
Q2
R
2.5V
LM385-2.5
Q5
LM385-2.5
300k
Q9
Q6
100k
REFERENCE FROM
A 9V BATTERY
Q8
500Ω
Q14
60k
OPERATION OVER A
WIDE SUPPLY RANGE
LM185-2.5 TA03
500k
–
LM185-2.5 SD01
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PACKAGE DESCRIPTIO
Dimensions in inches (millimeters) unless otherwise noted.
H Package, 2-Lead TO-46 Metal Can
Z package, 3-Lead TO-92 Plastic
0.060 ± 0.010
(1.524 ± 0.254)
0.209 – 0.219
(5.309 – 5.537)
0.178 – 0.195
(4.521 – 4.953)
0.140 ± 0.010
(3.556 ± 0.127)
0.080 – 0.100
(2.032 – 2.540)
0.015
0.500
(0.381)
(12.700) MAX
MIN
10° NOM
0.060 ± 0.005
(1.524± 0.127)
DIA
0.025
(0.635)
MAX
0.016 – 0.019
(0.406 – 0.483)
DIA
0.050
(1.270)
TYP
0.180 ± 0.005
(4.572 ± 0.127)
0.90
(2.286)
NOM
0.180 ± 0.005
(4.572 ± 0.127)
0.100
(2.540)
TYP
0.050
(1.270)
TYP
FOR 3-LEAD PACKAGE ONLY
0.020 ± 0.003
(0.508 ± 0.076)
45°
0.028 – 0.048
(0.711 – 1.219)
0.036 – 0.046
(0.914 – 1.168)
H3(46) 0592
TJMAX
θJA
5°
NOM
0.050
(1.270)
MAX
UNCONTROLLED
LEAD DIA
0.500
(12.79)
MIN
0.015 ± 0.02
(0.381 ± 0.051)
0.016 ± 0.03
(0.406 ± 0.076)
0.050 ± 0.005
(1.270 ± 0.127)
Z3 1191
θJC
θJA
TJMAX
150°C 440°C/W 80°CW
100°C 160°C/W
S8 package, 8-Lead Plastic SOIC
0.189 – 0.197
(4.801 – 5.004)
0.010 – 0.020
× 45°
(0.254 – 0.508)
8
0.053 – 0.069
(1.346 – 1.752)
0.016 – 0.050
0.406 – 1.270
0.050
(1.270)
BSC
0.014 – 0.019
(0.355 – 0.483)
TJMAX
5
Linear Technology Corporation
0.228 – 0.244
(5.791 – 6.197)
0.150 – 0.157
(3.810 – 3.988)
θJA
150°C 220°C/W
4
6
0.004 – 0.010
(0.101 – 0.254)
0.008 – 0.010
(0.203 – 0.254)
0°– 8° TYP
7
S8 0392
1
2
3
4
LT/GP 0892 1K REV B
1630 McCarthy Blvd., Milpitas, CA 95035-7487
(408) 432-1900 ● FAX: (408) 434-0507 ● TELEX: 499-3977
 LINEAR TECHNOLOGY CORPORATION 1992