VERY HIGH ACCURACY: 2.500 V OUTPUT 200 V
EXTREMELY LOW DRIFT: 0.8 ppm/C 55C to +125C
LOW WARM-UP DRIFT: 1 ppm Typ.
EXCELLENT STABILITY: 6 ppm/1000 Hrs. Typ.
EXCELLENT LINE REGULATION: 3 ppm/V Typ.
HERMETIC 14-PIN CERAMIC DIP
MILITARY PROCESSING OPTION
VRE110/111/112
Precision
Reference Supplies
DESCRIPTION
APPLICATIONS
PRECISION A/D and D/A CONVERTERS
TRANSDUCER EXCITATION
ACCURATE COMPARATOR THRESHOLD
REFERENCE
HIGH RESOLUTION SERVO SYSTEMS
DIGITAL VOLTMETERS
HIGH PRECISION TEST AND
MEASUREMENT INSTRUMENTS
FEATURES
SELECTION GUIDE
VRE110 Series Precision Voltage References
provide ultrastable +2.500V (VRE110), -2.500V
(VRE101) and 2.500V (VRE102) outputs with
200 V initial accuracy and temperature
coefficient as low as 0.8 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 VRE110 series the
most accurate and stable 2.5V reference
available.
VRE110/111/112 devices are available in two
operating temperature ranges, -25C to +85C
and -55C to +125C, and two performance
Type
Output
Temperature
Operating Range
Max. Volt
Deviation
VRE110C
+2.5V
-25C to +85C
200 V
VRE110CA
+2.5V
-25C to +85C
100 V
VRE110M
+2.5V
-55C to +125C
400 V
VRE110MA
+2.5V
-55C to +125C
200 V
VRE111C
-2.5V
-25C to +85C
200 V
VRE111CA
-2.5V
-25C to +85C
100 V
VRE111M
-2.5V
-55C to +125C
400 V
VRE111MA
-2.5V
-55C to +125C
200 V
VRE112C
2.5V
-25C to +85C
200 V
VRE112CA
2.5V
-25C to +85C
100 V
VRE112M
2.5V
-55C to +125C
400 V
VRE112MA
2.5V
-55C to +125C
200 V
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.
VRE110DS REV. D NOV 2000
THALER CORPORATION 2015 N. FORBES BOULEVARD TUCSON, AZ. 85745 (520) 882-4000
MODEL
C
CA
M
MA
PARAMETERS
MIN
TYP MAX
MIN
TYP MAX MIN
TYP MAX MIN TYP MAX
UNITS
ABSOLUTE MAXIMUM RATINGS
Power Supply
13.5
22
*
*
*
*
*
*
V
Operating Temperature -25
85
*
*
-55
125
-55
125
C
Storage Temperature
-65
150
*
*
*
*
*
*
C
Short Circuit Protection
Continuous
*
*
*
OUTPUT VOLTAGE
VRE110
+2.5
*
*
*
V
VRE111
-2.5
*
*
*
V
VRE112
2.5
*
*
*
V
OUTPUT VOLTAGE ERRORS
Initial Error
300
200
300
200
V
Warmup Drift
2
1
2
1
ppm
Tmin - Tmax
200
100
400
200
V
Long-Term Stability
6
*
*
*
ppm/1000hr.
Noise (.1-10Hz)
1.0
*
*
*
Vpp
OUTPUT CURRENT
Range
10
*
*
*
mA
REGULATION
Line
3
10
*
*
*
*
*
*
ppm/V
Load
3
*
*
*
ppm/mA
OUTPUT ADJUSTMENT
Range
20
*
*
*
mV
Temperature Coefficient
1
*
*
*
V/C/mV
POWER SUPPLY CURRENTS
VRE110 +PS
5
7
*
*
*
*
*
*
mA
VRE110/111 -PS
5
7
*
*
*
*
*
*
mA
VRE112 +PS
7
9
*
*
*
*
*
*
mA
VRE112 -PS
4
6
*
*
*
*
*
*
mA
VRE110/111/112
NOTES: *Same as C Models.
1.Using the box method, the specified value is the
maximum deviation from the output voltage at 25C
over the specified operating temperature range.
2.The specified values are unloaded.
(1)
(2)
Vps =15V, T = 25C, RL = 10k
?
unless otherwise noted.
ELECTRICAL SPECIFICATIONS
VRE110DS REV. D NOV 2000
TYPICAL PERFORMANCE CURVES
VRE110DS REV. D NOV 2000
Temperature
o
C
VRE110/111/112C
V
OUT
vs. TEMPERATURE
V
OUT
vs. TEMPERATURE
V
OUT
vs. TEMPERATURE
Temperature
o
C
VRE110/111/112CA
Temperature
o
C
VRE110/111/112M
Temperature
o
C
VRE110/111/112MA
QUIESCENT CURRENT VS. TEMP
Temperature
o
C
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
VRE110/111
VRE112
QUIESCENT CURRENT VS. TEMP
Temperature
o
C
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
POSITIVE OUTPUT
NEGATIVE OUTPUT
QUIESCENT CURRENT VS. TEMP
Temperature
o
C
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
THEORY OF OPERATION
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
2.500V 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.
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 VRE110
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.
DISCUSSION OF PERFORMANCE
APPLICATION INFORMATION
Figure 1 shows the proper connection of the
VRE110 series voltage reference with the optional
trim resistors. When trimming the VRE112, 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 VRE110 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.
VRE110
VRE112
VRE110DS REV. D NOV 2000