Datasheet

LM199/LM399
LM199A/LM399A
3
LM199399fb
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: The substrate is electrically connected to the negative terminal
of the temperature stabilizer. The voltage that can be applied to either
terminal of the reference is 40V more positive or 0.1V more negative than
the substrate.
Note 3: These specifi cations apply for 30V applied to the temperature
stabilizer and –55°C ≤ T
A
≤ 125°C for the LM199; and 0°C ≤ T
A
≤ 70°C for
the LM399.
Reverse Characteristics Dynamic Impedance Stabilization Time
ELECTRICAL CHARACTERISTICS
Note 4: Devices with maximum guaranteed long-term stability of
20ppm/√kH are available. Drift decreases with time.
Note 5: This initial current can be reduced by adding an appropriate
resistor and capacitor to the heater circuit. See the Typical Performance
Characteristics graphs to determine values.
Note 6: Guaranteed by “Reverse Breakdown Change with Current.”
TYPICAL PERFOR A CE CHARACTERISTICS
UW
HEATER ON TIME (SECONDS)
0
OUTPUT (mV)
–1
0
1
16
LM199 G03
–2
–3
–4
4
8
12
20
T
A
= 25°C
V
H
= 15V
T
A
= –55°C
Initial Heater Current Heater Current Heater Current
TURN ON TEMPERATURE (°C)
–55
0
INITIAL HEATER CURRENT (mA)
50
150
200
250
–15
25
45 125
LM199 G04
100
–35 5
65
85
105
V
H
= 40V
TEMPERATURE (°C)
–55
HEATER CURRENT (mA)
40
60
105
LM199 G05
20
0
–15
25
65
–35
5
45
85
80
V
H
= 10V
V
H
= 20V
V
H
= 40V
V
H
= 30V
TIME (SECONDS)
0
HEATER CURRENT (mA)
160
140
120
100
80
60
40
20
0
16
LM199 G06
4 8 12 142 6 10 18
V
H
= 10V
V
H
= 20V
T
A
= 25°C
V
H
= 30V
V
H
= 40V
REVERSE VOLTAGE (V)
6.25
0.01
REVERSE CURRENT (mA)
0.1
1
10
100
6.45 6.65
LM199 G01
6.85 7.05
T
J
= 25°C
STABILIZED
(T
J
≈ 90°C)
FREQUENCY (Hz)
10
0.1
DYNAMIC IMPEDANCE (Ω)
10
100
100 1k 10k 100k
LM199 G02
1
T
J
= 25°C
STABILIZED
(T
J
≈ 90°C)