LM285 1.2, LM385 1.2, LM385B 1.2
MICROPOWER VOLTAGE REFERENCES
SLVS075I − APRIL 1989 − REVISED DECEMBER 2005
D
Operating Current Range
D
D
D
D
D
− LM285 . . . 10
µA
to 20 mA
− LM385 . . . 15
µA
to 20 mA
− LM385B . . . 15
µA
to 20 mA
1% and 2% Initial Voltage Tolerance
Reference Impedance
− LM385 . . . 1
Ω
Max at 25°C
− All Devices . . . 1.5
Ω
Max Over Full
Temperature Range
Very Low Power Consumption
Applications
− Portable Meter References
− Portable Test Instruments
− Battery-Operated Systems
− Current-Loop Instrumentation
− Panel Meters
Interchangeable With Industry Standard
LM285-1.2 and LM385-1.2
LM285-1.2 . . . D PACKAGE
LM385-1.2 . . . D, PS, OR PW PACKAGE
LM385B-1.2 . . . D OR PW PACKAGE
(TOP VIEW)
NC
NC
NC
ANODE
1
2
3
4
8
7
6
5
CATHODE
NC
NC
NC
NC − No internal connection
LM285-1.2, LM385-1.2, LM385B-1.2 . . . LP PACKAGE
(TOP VIEW)
ANODE
CATHODE
NC
NC − No internal connection
description/ordering information
These micropower, two-terminal, band-gap voltage references operate over a 10-µA to 20-mA current range
and feature exceptionally low dynamic impedance and good temperature stability. On-chip trimming provides
tight voltage tolerance. The band-gap reference for these devices has low noise and long-term stability.
ORDERING INFORMATION
TA
VZ
TOLERANCE
SOIC (D)
SOP (PS)
2%
TO-226 / TO-92 (LP)
TSSOP (PW)
SOIC (D)
1%
TO-226 / TO-92 (LP)
TSSOP (PW)
SOIC (D)
TO-226 / TO-92 (LP)
PACKAGE†
Tube of 75
Reel of 2000
Reel of 2000
Tube of 1000
Reel of 2000
Tube of 150
0 C 70°C
0°C to 70 C
Reel of 2000
Tube of 75
Reel of 2000
Tube of 1000
Reel of 2000
Tube of 150
Reel of 2000
Tube of 75
−40 C 85°C
−40°C to 85 C
1%
Reel of 2000
Tube of 1000
ORDERABLE
PART NUMBER
LM385D-1-2
LM385DR-1-2
LM385PSR-1-2
LM385LP-1-2
LM385LPR-1-2
LM385PW-1-2
LM385PWR-1-2
LM385BD-1-2
LM385BDR-1-2
LM385BLP-1-2
LM385BLPR-1-2
LM385BPW-1-2
LM385BPWR-1-2
LM285D-1-2
LM285DR-1-2
LM285LP-1-2
285-12
285-12
385B12
385B12
385B12
385-12
385-12
385-12
L385-12
TOP-SIDE
MARKING
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available
at www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright
2005, Texas Instruments Incorporated
POST OFFICE BOX 655303
•
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1
LM285 1.2, LM385 1.2, LM385B 1.2
MICROPOWER VOLTAGE REFERENCES
SLVS075I − APRIL 1989 − REVISED DECEMBER 2005
description/ordering information (continued)
The design makes these devices exceptionally tolerant of capacitive loading and, thus, easier to use in most
reference applications. The wide dynamic operating temperature range accommodates varying current
supplies, with excellent regulation.
The extremely low power drain of this series makes them useful for micropower circuitry. These voltage
references can be used to make portable meters, regulators, or general-purpose analog circuitry, with battery
life approaching shelf life. The wide operating current range allows them to replace older references with
tighter-tolerance parts.
symbol
ANODE
CATHODE
schematic
CATHODE
Q13
7.5 kΩ
600 kΩ
Q12
Q7
Q4
Q11
50 kΩ
Q3
Q1
20 pF
Q2
Q5
20 pF
Q9
Q10
300 kΩ
200 kΩ
Q6
Q8
Q14
100 kΩ
500
Ω
60 kΩ
ANODE
NOTE A: Component values shown are nominal.
2
POST OFFICE BOX 655303
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LM285 1.2, LM385 1.2, LM385B 1.2
MICROPOWER VOLTAGE REFERENCES
SLVS075I − APRIL 1989 − REVISED DECEMBER 2005
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)
†
Reverse current, I
R
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 mA
Forward current, I
F
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 mA
Package thermal impedance,
θ
JA
(see Notes 1 and 2): D package . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97°C/W
LP package . . . . . . . . . . . . . . . . . . . . . . . . . . 140°C/W
PS package . . . . . . . . . . . . . . . . . . . . . . . . . . . 95°C/W
PW package . . . . . . . . . . . . . . . . . . . . . . . . . 149°C/W
Operating virtual junction temperature, T
J
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C
Storage temperature range, T
stg
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. Maximum power dissipation is a function of TJ(max)
,
θ
JA, and TA. The maximum allowable power dissipation at any allowable ambient
temperature is PD = (TJ(max) − TA)/
θ
JA. Operation at the absolute maximum TJ of 150°C can affect reliability.
2. The package thermal impedance is calculated in accordance with JESD 51-7.
recommended operating conditions
MIN
IZ
TA
Reference current
Operating free-air temperature range
LM285-1.2
LM385-1.2, LM385B-1.2
0.01
−40
0
MAX
20
85
70
UNIT
mA
°C
POST OFFICE BOX 655303
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3
LM285 1.2, LM385 1.2, LM385B 1.2
MICROPOWER VOLTAGE REFERENCES
SLVS075I − APRIL 1989 − REVISED DECEMBER 2005
electrical characteristics at specified free-air temperature
PARAMETER
VZ
Reference
voltage
Average
temperature
coefficient of
reference
voltage§
Change in
reference
voltage with
current
Long-term
change in
reference
voltage
Minimum
reference
current
Reference
impedance
IZ = 100
µA,
f = 25 Hz
TEST
CONDITIONS
IZ = I(min)
to 20 mA‡
TA†
25°C
LM285-1.2
MIN
1.223
TYP
1.235
MAX
1.247
LM385-1.2
MIN
1.21
TYP
1.235
MAX
1.26
LM385B-1.2
MIN
1.223
TYP
1.235
MAX
1.247
UNIT
V
α
VZ
IZ = I(min)
to 20 mA‡
Full range
±20
±20
±20
ppm/°C
∆V
Z
IZ = I(min)
to 1 mA‡
IZ = 1 mA
to 20 mA
25°C
Full range
25°C
Full range
±20
1
1.5
12
30
±20
1
1.5
20
30
±20
1
1.5
20
30
mV
∆V
Z/∆t
IZ = 100
µA
25°C
ppm/khr
IZ(min)
Full range
25°C
Full range
25°C
8
0.2
10
0.6
1.5
8
0.4
15
1
1.5
8
0.4
15
1
1.5
µA
zz
Vn
Ω
µV
IZ = 100
µA,
Broadband
f = 10 Hz to
noise voltage
10 kHz
60
60
60
† Full range is −40°C to 85°C for the LM285-1.2 and 0°C to 70°C for the LM385-1.2 and LM385B-1.2.
‡ I(min) = 10
µA
for the LM285-1.2 and 15
µA
for the LM385-1.2 and LM385B-1.2
§ The average temperature coefficient of reference voltage is defined as the total change in reference voltage divided by the specified temperature
range.
4
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LM285 1.2, LM385 1.2, LM385B 1.2
MICROPOWER VOLTAGE REFERENCES
SLVS075I − APRIL 1989 − REVISED DECEMBER 2005
TYPICAL CHARACTERISTICS
†
REVERSE CURRENT
vs
REVERSE VOLTAGE
REFERENCE VOLTAGE CHANGE
vs
REVERSE CURRENT
TA = −55°C to 125°C
∆V
Z − Reference Voltage Change − mV
12
I R − Reverse Current −
µ
A
10
8
4
1
0
0.1
0
0.2
0.4
0.6
0.8
1
1.2
1.4
−4
0.01
VR − Reverse Voltage − V
Figure 1
FORWARD VOLTAGE
vs
FORWARD CURRENT
1.2
1.245
TA = 25°C
0.8
V Z − Reference Voltage − V
V F − Forward Voltage − V
1.24
1.235
0.4
1.23
1.225
0
0.01
1.220
−55 −35
0.1
1
10
100
IF − Forward Current − mA
Figure 3
† Data at high and low temperatures are applicable only within the rated operating free-air temperature ranges of the various devices.
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
TA = −55°C to 125°C
0.1
1
10
100
IR − Reverse Current − mA
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎ
100
16
Figure 2
REFERENCE VOLTAGE
vs
FREE-AIR TEMPERATURE
−15
5
25
45
65
85
105 125
TA − Free-Air Temperature −
°C
Figure 4
5
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