ETC VRE119MA

VRE117/118/119
Precision
Reference Supplies
THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000
FEATURES
APPLICATIONS
• VERY HIGH ACCURACY: 3.000 V OUTPUT ±200 µV
• PRECISION A/D and D/A CONVERTERS
• EXTREMELY LOW DRIFT: 0.6 ppm/°C 55°C to +125°C
• TRANSDUCER EXCITATION
• LOW WARM-UP DRIFT: 1 ppm Typ.
• ACCURATE COMPARATOR THRESHOLD
REFERENCE
• EXCELLENT STABILITY: 6 ppm/1000 Hrs. Typ.
• HIGH RESOLUTION SERVO SYSTEMS
• EXCELLENT LINE REGULATION: 3 ppm/V Typ.
• DIGITAL VOLTMETERS
• HERMETIC 14-PIN CERAMIC DIP
• MILITARY PROCESSING OPTION
• HIGH PRECISION TEST and
MEASUREMENT INSTRUMENTS
DESCRIPTION
VRE117 Series Precision Voltage References
provide ultrastable +3.000V (VRE117), -3.000V
(VRE118) and ±3.000V (VRE119) outputs with
±0.200 mV initial accuracy and temperature
coefficient as low as 0.6 ppm/°C over the full
military temperature range. This improvement in
accuracy is made possible by a unique,
proprietary
multipoint
laser
compensation
technique developed by Thaler Corporation.
Significant improvements have been made in
other performance parameters as well, including
initial accuracy, warm-up drift, line regulation, and
long-term stability, making the VRE117 series the
most accurate and stable 3.0V reference
available.
SELECTION GUIDE
Type
Output
Temperature
Operating Range
Max. Volt
Deviation
VRE117C
VRE117CA
VRE117M
VRE117MA
+3.0V
+3.0V
+3.0V
+3.0V
-25°C to +85°C
-25°C to +85°C
-55°C to +125°C
-55°C to +125°C
200 µV
100 µV
400 µV
200 µV
VRE118C
VRE118CA
VRE118M
VRE118MA
-3.0V
-3.0V
-3.0V
-3.0V
-25°C to +85°C
-25°C to +85°C
-55°C to +125°C
-55°C to +125°C
200 µV
100 µV
400 µV
200 µV
VRE119C
VRE119CA
VRE119M
VRE119MA
±3.0V
±3.0V
±3.0V
±3.0V
-25°C to +85°C
-25°C to +85°C
-55°C to +125°C
-55°C to +125°C
200 µV
100 µV
400 µV
200 µV
VRE117/118/119 devices are available in two
operating temperature ranges, -25°C to +85°C
and -55°C to +125°C, and two performance
grades. All devices are packaged in 14-pin hermetic ceramic packages for maximum long-term stability. "M"
versions are screened for high reliability and quality.
Superior stability, accuracy, and quality make these references ideal for precision applications such as A/D
and D/A converters, high-accuracy test and measurement instrumentation, and transducer excitation.
VRE117DS REV. C NOV 2000
ELECTRICAL SPECIFICATIONS
VRE117/118/119
Vps =±15V, T = 25°C, RL = 10kΩ unless otherwise noted.
MODEL
C
PARAMETERS
MIN
CA
TYP MAX
MIN
M
TYP MAX
MA
MIN
TYP MAX MIN
*
-55
*
*
125
*
TYP
MAX
UNITS
*
125
*
V
°C
°C
ABSOLUTE MAXIMUM RATINGS
Power Supply
±13.5
±22
Operating Temperature -25
85
Storage Temperature
-65
150
Short Circuit Protection
Continuous
*
*
*
*
*
*
*
-55
*
*
*
*
*
*
*
*
*
*
*
*
*
OUTPUT VOLTAGE
VRE117
VRE118
VRE119
+3.0
-3.0
±3.0
V
V
V
OUTPUT VOLTAGE ERRORS
Initial Error
Warmup Drift
Tmin - Tmax (1)
Long-Term Stability
Noise (.1-10Hz)
300
200
2
300
1
200
100
6
1.5
200
2
1
400
*
*
200
*
*
*
*
µV
ppm
µV
ppm/1000hr.
µVpp
OUTPUT CURRENT
Range
±10
*
*
*
mA
REGULATION
Line
Load
3
3
10
*
*
*
*
*
*
*
*
*
ppm/V
ppm/mA
OUTPUT ADJUSTMENT
Range
Temperature Coefficient
POWER SUPPLY CURRENTS
5
1
*
*
*
*
mV
µV/°C/mV
(2)
VRE117 +PS/ -PS
VRE119 +PS
VRE118/119 -PS
NOTES:
*
*
5
7
4
7
9
6
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
mA
mA
mA
*Same as C Models.
1.Using the box method, the specified value is the
maximum deviation from the output voltage at 25°C
over the specified operating temperature range.
2.The specified values are unloaded.
VRE117DS REV. C NOV 2000
TYPICAL PERFORMANCE CURVES
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
Temperature oC
VRE117/118/119C
Temperature oC
VRE117/118/119CA
Temperature oC
VRE117/118/119M
Temperature oC
VRE117/118/119MA
VRE117/118
QUIESCENT CURRENT VS. TEMP
Temperature oC
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
VRE119
POSITIVE OUTPUT
QUIESCENT CURRENT VS. TEMP
Temperature oC
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
NEGATIVE OUTPUT
QUIESCENT CURRENT VS. TEMP
Temperature oC
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
VRE117DS REV. C NOV 2000
DISCUSSION OF PERFORMANCE
THEORY OF OPERATION
APPLICATION INFORMATION
The following discussion refers to the schematic
below. A FET current source is used to bias a 6.3V
zener diode. The zener voltage is divided by the
resistor network R1 and R2. This voltage is then
applied to the noninverting input of the operational
amplifier which amplifies the voltage to produce a
3.000V output. The gain is determined by the
resistor networks R3 and R4: G=1 + R4/R3. The
6.3V zener diode is used because it is the most
stable diode over time and temperature.
Figure 1 shows the proper connection of the
VRE117 series voltage reference with the optional
trim resistors. When trimming the VRE119, the
positive voltage should be trimmed first since the
negative voltage tracks the positive side. Pay careful
attention to the circuit layout to avoid noise pickup
and voltage drops in the lines.
The current source provides a closely regulated
zener current, which determines the slope of the
reference's voltage vs. temperature function. By
trimming the zener current, a lower drift over
temperature can be achieved. But since the voltage
vs. temperature function is nonlinear, this method
leaves a residual error over wide temperature
ranges.
To remove this residual error, Thaler Corporation
has developed a nonlinear compensation network of
thermistors and resistors that is used in the VRE117
series references. This proprietary network
eliminates most of the nonlinearity in the voltage vs.
temperature function. By then adjusting the slope,
Thaler Corporation produces a very stable voltage
over wide temperature ranges. This network is less
than 2% of the overall network resistance so it has a
negligible effect on long term stability.
The VRE117 series voltage references have the
ground terminal brought out on two pins (pin 6 and
pin 7) which are connected together internally. This
allows the user to achieve greater accuracy when
using a socket. Voltage references have a voltage
drop across their power supply ground pin due to
quiescent current flowing through the contact
resistance. If the contact resistance was constant with
time and temperature, this voltage drop could be
trimmed out. When the reference is plugged into a
socket, this source of error can be as high as 20ppm.
By connecting pin 7 to the power supply ground and
pin 6 to a high impedance ground point in the
measurement circuit, the error due to the contact
resistance can be eliminated. If the unit is soldered
into place the contact resistance is sufficiently small
that it doesn't effect performance.
VRE117
VRE119
VRE117DS REV. C NOV 2000
EXTERNAL CONNECTIONS
FIGURE 1
1. Optional Fine Adjust for approximately ±5mV. VRE118 trim pot center tap connects to -15V.
PIN CONFIGURATION
TOP VIEW
TOP VIEW
NC
FINE ADJ.
NC
+3.0V (-3.0V)
NC
-PS
-3.0V
FINE ADJ.
VRE117
(VRE118)
FINE +ADJ.
FINE -ADJ.
+3.0V
FINE +ADJ.
FINE -ADJ.
VRE119
+PS
+PS (-PS)
-PS
NC
NC
NC
NC
REF. GND
NC
REF. GND
NC
GND
NC
GND
NC
MECHANICAL
14-PIN HYBRID
PACKAGE
INCHES
DIM
MIN
MAX
MILLIMETER
MIN
INCHES
MILLIMETER
MAX
DIM
MIN
MAX
MIN
MAX
E
.480
.500
12.1
12.7
A
.120
.155
3.0
4.0
L
.195
.215
4.9
5.4
Q
.015
.035
0.4
0.9
D
.775
.805
19.7
20.4
Q1
N/A
.030
N/A
0.7
B
.016
.020
0.4
0.5
C
.009
.012
0.2
0.3
B1
.038
.042
0.9
1.0
G1
.290
.310
7.3
7.8
B2
.095
.105
2.4
2.6
S
.085
.105
2.1
2.6
P
.004
.006
0.10
0.15
VRE117DS REV. C NOV 2000