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LT1031 / LH0070 Precision 10V Reference

DESCRIPTIO

LT1031 / LH0070 Precision 10V Reference
FEATURES
DESCRIPTIO
, LTC and LT are registered trademarks of Linear Technology Corporation. See LH0070 Electrical Characteristics table and AD581 cross reference guide.
APPLICATIO S
A-to-D and D-to-A Converters Precision Regulators Digital Voltmeters lnertial Navigation Systems Precision Scales Portable Reference Standard
TYPICAL APPLICATIO
Basic Positive and Negative Connections
Distribution of Output Accuracy
LT1031 · TA01
LT1031 · TA02
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LT1031 / LH0070
ABSOLUTE
(Note 1)
RATI GS
PACKAGE / ORDER I FOR ATIO
BOTTOM VIEW INPUT
ORDER PART NUMBER LH0070-0H LH0070-1H LH0070-2H LT1031BMH LT1031DMH LT1031BCH LT1031CCH LT1031DCH
LT1031 · POI01
Consult LTC Marketing for parts specified with wider operating temperature ranges.
ELECTRICAL CHARACTERISTICS
SYMBOL VR PARAMETER Output Voltage (Note 2)
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Output Voltage Temperature Coefficient (Note 3)
VR VIN
Line Regulation (Note 4)
IQ IMIN
en VR Time
Output Voltage Noise Long Term Stability of Output Voltage Temperature Hysteresis of Output
LT1031 / LH0070
ELECTRICAL CHARACTERISTICS
VR VIN
Note 4: Line and load regulation are measured on a pulse basis. Output changes due to die temperature change must be taken into account separately. Package thermal resistance is 150°C / W. Note 5: Shunt mode regulation is measured with the input open. With the input connected, shunt mode current can be reduced to 0mA. Load regulation will remain the same. Note 6: Temperature drift is guaranteed from -25°C to 85°C on LH0070. Note 7: See curve for guaranteed minimum VIN versus IOUT. Note 8: Guaranteed by design.
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LT1031 / LH0070 CROSS REFERENCE
The following cross reference guide may be used to select LT1031 grades which meet or exceed output voltage, temperature drift, load and line regulation, and output current specifications of the AD581 reference. Parameters such as noise, hysteresis, and long term stability will be significantly better for all LT1031 grades compared to the AD581.
CROSS REFERENCE GUIDE / LT1031 TO AD581 AD581J AD581K AD581L A0581S A0581U order LT1031DCH order LT1031CCH order LT1031BCH order LT1031DMH order LT1031BMH
TYPICAL PERFOR A CE CHARACTERISTICS
Ripple Rejection
115 110 REJECTION (dB)
REJECTION (dB)
INPUT VOLTAGE (V)
15 20 25 30 INPUT VOLTAGE (V)
Start-Up (Series Mode)
OUTPUT VOLTAGE (V)
NOISE VOLTAGE (nV / Hz)
OUTPUT VOLTAGE (V)
Ripple Rejection
130 120 110 100 90 80 70 60 50 35 40 10 100 1k FREQUENCY (Hz) 10k
LT1031 · TPC02 LT1031 · TPC01
Minimum Input Voltage
11.6 11.4 11.2 11.0 10.8 10.6 10.4 10.2 10.0 0 2 4 6 8 10 12 14 16 18 20 OUTPUT CURRENT (mA)
LT1031 · TPC03
GUARANTEED CURVE-ALL TEMPS
Start-Up (Shunt Mode)
-12V 1k VOUT OUT NC IN GND
Output Voltage Noise Spectrum
6 4 TIME (µs)
0 10 100 1k FREQUENCY (Hz) 10k
LT1031 · TPC06
LT1031 · TPC04
LT1031 · TPC05
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LT1031 / LH0070 TYPICAL PERFOR A CE CHARACTERISTICS
Output Voltage Noise
RMS NOISE (µV)
OUTPUT VOLTAGE (V)
10 8 6 4 2 0 10 100 1k BANDWIDTH (Hz) 10k
LT1031 · TPC07
Input Supply Current
INPUT CURRENT (mA)
CURRENT INTO OUTPUT (mA)
25 30 INPUT VOLTAGE (V)
Thermal Regulation
OUTPUT VOLTAGE CHANGE OUTPUT CHANGE (mV)
OUTPUT VOLTAGE CHANGE
40 60 80 100 120 140 TIME (ms) INDEPENDENT OF TEMPERATURE COEFFICIENT 0 20
LT1031 · TPC13
LT1031 · TPC10
Load Regulation
Output Voltage Temperature
-5 -10 -8 -6 -4 -2 0 2 4 6 8 SOURCING SINKING OUTPUT CURRENT (mA)
50 25 75 0 TEMPERATURE (°C)
LT1031 · TPC08
LT1031 · TPC09
Shunt Characteristics
1.8 1.6 INPUT PIN OPEN
Shunt Mode Current Limit
60 50 40 30 20 10 0 INPUT PIN IS OPEN
2 4 6 10 8 OUTPUT TO GROUND VOLTAGE (V)
6 8 10 12 14 OUTPUT VOLTAGE (V)
LT1031 · TPC11
LT1031 · TPC12
3 4 5 6 7 8 TIME (µs) NOTE VERTICAL SCALE CHANGE BETWEEN SOURCING AND SINKING
LT1031 · TPC14
LT1031 · TPC15
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LT1031 / LH0070 TYPICAL PERFOR A CE CHARACTERISTICS
Output Noise 0.1Hz to 10Hz
OUTPUT VOLTAGE NOISE (10µV / DIV)
APPLICATIO S I FOR ATIO
Trimming Output Voltage
Output Voltage Trimming
LT1031 VIN IN GND R2 4.3k R1 5 -15V CAN BE INCREASED TO 5.6k FOR LT1031B AND LH0070-2 INCREASE TO 10 FOR LT1031D R3 50k OUT VOUT
MAXIMUM TEMPERATURE COEFFICIENT FOR 1 / 2LSB ERROR (ppm / °C)
LT1031 · TA04
10µV (1ppm)
4 3 2 TIME (MINUTES)
LT1031 · TPC16
Effect of Reference Drift on System Accuracy A large portion of the temperature drift error budget in many systems is the system reference voltage. The graph below indicates the maximum temperature coefficient allowable if the reference is to contribute no more than 1 / 2LSB error to the overall system performance. The example shown is a 12-bit system designed to operate over a temperature range from 25°C to 65°C. Assuming the system calibration is performed at 25°C, the temperature span is 40°C. The graph shows that the temperature coefficient of the reference must be no worse than 3ppm / °C if it is to contribute less than 1 / 2LSB error. For this reason, the LT1031 has been optimized for low drift.
Maximum Allowable Reference Drift
8-BIT
10-BIT
12-BIT 14-BIT
10 20 30 40 50 60 70 80 90 100 TEMPERATURE SPAN (°C)
LT1031 · TA03
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LT1031 / LH0070
APPLICATIO S I FOR ATIO
Standard Series Mode
LT1031 INPUT IN GND OUT KEEP THIS LINE RESISTANCE LOW
GROUND RETURN
LT1031 · TA05
Series Mode with Boost Transistor
INPUT R1 220 2N3906 IN LT1031 GND OUT R2 5.6k LOAD GROUND RETURN OPTIONAL-REDUCES CURRENT IN OUTPUT SENSE LEAD
LT1031 · TA06
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LT1031 / LH0070
APPLICATIO S I FOR ATIO
There is nothing magical about foam cups-any enclosure which blocks air flow from the reference will do. Smaller enclosures are better since they do not allow the build-up of internally generated air movement. Naturally, heat generating components external to the reference itself should not be included inside the enclosure.
OUTPUT VOLTAGE NOISE (20µV / DIV)
APPLICATIO CIRCUITS
Negative Series Reference
15V R1 4.7k IN R2 4.7k D1 15V GND -10V AT 50mA
LT1031 · AC01
LT1031 OUT
Q1 2N2905
Boosted Output Current with Current Limit
V+ 12.8V D1 LED R1 220 8.2
2N2905 IN LT1031 GND OUT 10V AT 100mA 2µF SOLID TANT
GLOWS IN CURRENT LIMIT DO NOT OMIT
LT1031 · AC03
Noise Induced by Air Turbulence (TO-5 Package)
FOAM CUP REMOVED
8 6 4 TIME (MINUTES)
LT1031 · TA07
Boosted Output Current with No Current Limit
V+ 11.8V R1 220 2N2905 IN LT1031 GND OUT 10V AT 100mA 2µF SOLID TANT
LT1031 · AC02
Handling Higher Load Currents
15V 30mA
IN LT1031 GND OUT
SELECT R1 TO DELIVER TYPICAL LOAD CURRENT LT1031 WILL THEN SOURCE OR SINK AS NECESSARY TO MAINTAIN PROPER OUTPUT. DO NOT REMOVE LOAD, AS OUTPUT WILL BE DRIVEN (UNREGULATED) HIGH. LINE REGULATION IS DEGRADED IN THIS APPLICATION LT1031 · AC04
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LT1031 / LH0070
APPLICATIO CIRCUITS
Strain Gauge Conditioner for 350 Bridge
LM301A
100pF
LT1031 · AC05
Ultralinear Platinum Temperature Sensor
LT1031 OUT GND R2 5k R1 253k IN 20V
R9 100k
R8 10M
20V 7 LT1001 6
4 -15V
LT1031 · AC06
R4 20k
28mA LT1031 IN GND OUT 28.5mA 5V 350 STRAIN GUAGE BRIDGE R2 20k R3 2M
LT1012C
VOUT · 100
R14 5k R15 10k
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LT1031 / LH0070
APPLICATIO CIRCUITS
2-Pole Lowpass Filtered Reference
MYLAR 1µF VIN
TOTAL NOISE 2µVRMS 1Hz f 10kHz
-VREF
LT1031 · AC07
Negative Shunt Reference Driven by Current Source
LT1031 OUT GND -10V (ILOAD 1mA) 2.5mA
LM334
-11V TO -40V
LT1031 · AC08
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LT1031 / LH0070
APPLICATIO CIRCUITS
Precision DAC Reference with System TC Trim
EQUIVALENT SCHEMATIC
INPUT
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 its circuits as described herein will not infringe on existing patent rights.
D2 IN457 50k
8.45k
LT1031 · AC09
Q3 D1 D2 OUTPUT D3 Q1 R1
A1 D4 6.3V
Q2 GND
LT1031 · ES01
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LT1031 / LH0070
PACKAGE DESCRIPTIO U
H Package 3-Lead TO-39 Metal Can
(Reference LTC DWG # 05-08-1330)
.350 - .370 (8.890 - 9.398) .305 - .335 (7.747 - 8.509) .050 (1.270) MAX REFERENCE PLANE .165 - .185 (4.191 - 4.699) .016 - .019 (0.406 - 0.483) DIA .200 (5.080) TYP .500 (12.700) MIN .100 (2.540) PIN 1 .029 - .045 (0.737 - 1.143) .028 - .034 (0.711 - 0.864) .100 (2.540) 45°
H3(TO-39) 0801
LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND .050" BELOW THE REFERENCE PLANE .016 - .024 FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 - 0.610)
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Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 FAX: (408) 434-0507
LW / TP 1102 1K REV A · PRINTED IN USA
www.linear.com
LINEAR TECHNOLOGY CORPORATION 1984