1
LT1021
Precision Reference
Typical Distribution of Temperature Drift
OUTPUT DRIFT (ppm/°C)
–5
UNITS (%)
24
21
18
15
12
9
6
3
– 0
3
1021 TA01
–3 –1 1 52–4 –2 0 4
DISTRIBUTION
OF THREE RUNS
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PP
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IC
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P
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L
Basic Positive and Negative Connections
LT1021
OUT
IN
GND
LT1021
(7 AND 10 ONLY)
OUT
IN
GND
V
OUT
–V
OUT
V
IN
NC
R1 =
V
OUT
– (V
–
)
I
LOAD
+ 1.5mA
–15V
(V
–
)
R1
1021 TA01
■
Pin Compatible with Most Bandgap Reference
Applications, Including Ref 01, Ref 02, LM368,
MC1400 and MC1404 with Greatly Improved
Stability, Noise and Drift
■
Ultralow Drift: 5ppm/
°
C Max Slope
■
Trimmed Output Voltage
■
Operates in Series or Shunt Mode
■
Output Sinks and Sources in Series Mode
■
Very Low Noise: <1ppm
P-P
(0.1Hz to 10Hz)
■
>100dB Ripple Rejection
■
Minimum Input/Output Differential of 1V
■
100% Noise Tested
U
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PP
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IC
AT
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■
A/D and D/A Converters
■
Precision Regulators
■
Digital Voltmeters
■
Inertial Navigation Systems
■
Precision Scales
■
Portable Reference Standard
, LTC and LT are registered trademarks of Linear Technology Corporation.
D
U
ESCRIPTIO
The LT
®
1021 is a precision reference with ultralow drift
and noise, extremely good long term stability and almost
total immunity to input voltage variations. The reference
output will both source and sink up to 10mA. Three
voltages are available: 5V, 7V and 10V. The 7V and 10V
units can be used as shunt regulators (two-terminal zeners)
with the same precision characteristics as the three-
terminal connection. Special care has been taken to mini-
mize thermal regulation effects and temperature
induced hysteresis.
The LT1021 references are based on a buried zener diode
structure that eliminates noise and stability problems
associated with surface breakdown devices. Further, a
subsurface zener exhibits better temperature drift and
time stability than even the best bandgap references.
Unique circuit design makes the LT1021 the first IC
reference to offer ultralow drift without the use of high
power on-chip heaters.
The LT1021-7 uses no resistive divider to set output
voltage, and therefore exhibits the best long term stability
and temperature hysteresis. The LT1021-5 and LT1021-
10 are intended for systems requiring a precise 5V or 10V
reference with an initial tolerance as low as ±0.05%.
S
F
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T
U
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