Datasheet VRE112MA, VRE112M, VRE112CA, VRE112C, VRE111MA Datasheet (THALER)

• VERY HIGH ACCURACY: 2.500 V OUTPUT ±200 µV

• EXTREMELY LOW DRIFT: 0.8 ppm/°C 55°C to +125°C

• 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 µV 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, -25°C to +85°C
and -55°C to +125°C, and two performance

Type

Output

Temperature

Operating Range

Max. Volt
Deviation

VRE110C +2.5V -25°C to +85°C 200 µV
VRE110CA +2.5V -25°C to +85°C 100 µV
VRE110M +2.5V -55°C to +125°C 400 µV
VRE110MA +2.5V -55°C to +125°C 200 µV

VRE111C -2.5V -25°C to +85°C 200 µV
VRE111CA -2.5V -25°C to +85°C 100 µV
VRE111M -2.5V -55°C to +125°C 400 µV
VRE111MA -2.5V -55°C to +125°C 200 µV

VRE112C ±2.5V -25°C to +85°C 200 µV
VRE112CA ±2.5V -25°C to +85°C 100 µV
VRE112M ±2.5V -55°C to +125°C 400 µV
VRE112MA ±2.5V -55°C to +125°C 200 µV

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 • [phone]

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 µV
Warmup Drift 2 1 2 1 ppm
Tmin - Tmax 200 100 400 200 µV
Long-Term Stability 6 * * * ppm/1000hr.
Noise (.1-10Hz) 1.0 * * * µVpp

OUTPUT CURRENT

Range ±10 * * * mA

REGULATION

Line 3 10 * * * * * * ppm/V
Load 3 * * * ppm/mA

OUTPUT ADJUSTMENT

Range 20 * * * mV
Temperature Coefficient 1 * * * µV/°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 25°C
over the specified operating temperature range.

2.The specified values are unloaded.

(1)

(2)

Vps =±15V, T = 25°C, RL = 10k? unless otherwise noted.

ELECTRICAL SPECIFICATIONS

VRE110DS REV. D NOV 2000

TYPICAL PERFORMANCE CURVES

VRE110DS REV. D NOV 2000

TemperatureoC

VRE110/111/112C

V

OUT

vs. TEMPERATURE

V

OUT

vs. TEMPERATURE

V

OUT

vs. TEMPERATURE

TemperatureoC

VRE110/111/112CA

TemperatureoC

VRE110/111/112M

TemperatureoC

VRE110/111/112MA

QUIESCENT CURRENT VS. TEMP

TemperatureoC

JUNCTION TEMP. RISE VS. OUTPUT CURRENT

Output Current (mA)

PSRR VS. FREQUENCY

Frequency (Hz)

VRE110/111

VRE112

QUIESCENT CURRENT VS. TEMP

TemperatureoC

JUNCTION TEMP. RISE VS. OUTPUT CURRENT

Output Current (mA)

PSRR VS. FREQUENCY

Frequency (Hz)

POSITIVE OUTPUT

NEGATIVE OUTPUT

QUIESCENT CURRENT VS. TEMP

TemperatureoC

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

14-PIN HYBRID
PACKAGE

TOP VIEW

TOP VIEW

VRE112

VRE110

(VRE111)

GND

REF. GND

NC

-PS

NC

NC

NC

FINE ADJ.

+2.5V (-2.5V)
FINE ADJ.

+PS (-PS)

NC

NC

NC

FINE +ADJ.
+2.5V
FINE +ADJ.

+PS
NC
NC
NC

GND

REF. GND

NC

-2.5V

FINE -ADJ.

FINE -ADJ.

-PS

EXTERNAL CONNECTIONS

FIGURE 1

MECHANICAL

PIN CONFIGURATION

1. Optional Fine Adjust for approximately ±5mV. VRE111 trim pot center tap connect to -15V.

VRE110DS REV. D NOV 2000

DIM MIN MAX MIN 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

INCHES MILLIMETER

INCHES MILLIMETER