ETC VRE405AD

VRE405
Precision
Dual Reference
THALER CORPORATION • 2015 N. FORBES BOULEVARD • TUCSON, AZ. 85745 • (520) 882-4000
FEATURES
PIN CONFIGURATION
• ±5.000 V OUTPUT ± 0.500 mV (.01%)
• TEMPERATURE DRIFT: 0.6 ppm/°C
N/C
1
- VOUT
2
14
N/C
13
+VOUT
3
VRE405
12
N/C
- VIN
4
TOP
VIEW
11
+VIN
N/C
5
10
N/C
REF. GND
6
9
N/C
GND
7
8
N/C
• LOW NOISE: 3 µVpp (0.1-10Hz)
N/C
• TRACKING ERROR: 0.3 mV max.
• EXCELLENT LINE REGULATION: 6ppm/V Typ.
• SURFACE MOUNT AND DIP PACKAGES
FIGURE 1
DESCRIPTION
The VRE405 is a low cost, high precision, ±5.0V
reference. Packaged in 14 pin DIP or SMT
packages, the device is ideal for new designs that
need a high performance reference.
The device provides ultrastable ±5.000V output
with ±0.500 mV (.01%) initial accuracy and a
temperature coefficient of 0.6 ppm/°C.
This
improvement in accuracy is made possible by a
unique, patented multipoint laser compensation
technique developed by Thaler Corporation.
Another key feature of this reference is the 0.3 mV
maximum tracking error between the positive and
negative output voltages over the operating
temperature range. This is extremely important in
high performance systems for reducing overall
system errors.
For designs which use the DIP package in a
socket, there is a reference ground pin to
eliminate the reference ground errors.
The VRE405 is recommended for use as a
reference for high precision D/A
and A/D
converters which require an external precision
reference. The device is ideal for calibrating
scale factor on high resolution A/D converters.
The VRE405 offers superior performance over
monolithic references.
SELECTION GUIDE
Model
Initial
Error
mV
Temp.
Coeff.
ppm/°C
Temp.
Range
°C
VRE405A
VRE405B
VRE405C
VRE405J
VRE405K
VRE405L
0.5
0.8
1.0
0.5
0.8
1.0
0.6
1.0
2.0
0.6
1.0
2.0
0°C to +70°C
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
For package option add D for DIP or S for Surface
Mount to end of model number.
VRE405DS REV. A MAY 1996
ELECTRICAL SPECIFICATIONS
VRE405
Vps = ±15V, T = 25°C, RL = 10KΩ unless otherwise noted.
MODEL
A/J
PARAMETER
MIN
TYP
B/K
MAX
C/L
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
V
°C
°C
°C
ABSOLUTE RATINGS
Power Supply
±13.5
±15
±22
Operating Temp. (A,B,C )
0
+70
Operating Temp. (J,K,L)
-40
+85
Storage Temperature
-65
+150
Short Circuit Protection
Continuous
*
*
*
*
OUTPUT VOLTAGE
VRE405
±5.00
V
OUTPUT VOLTAGE ERRORS
Initial Error (1)
Warmup Drift
Tmin - Tmax (2)
(3)
Tracking Error
Long-Term Stability
Noise (.1-10Hz)
0.50
0.80
1
1.00
2
0.6
0.3
3
1.0
0.4
6
3
2.0
0.5
*
*
*
*
mV
ppm
ppm/ °C
mV
ppm/1000hrs
µVpp
OUTPUT CURRENT
Range
±10
*
*
mA
REGULATION
Line
Load
POWER SUPPLY CURRENTS
10
*
*
*
*
*
*
ppm/V
ppm/mA
7
4
9
6
*
*
*
*
*
*
*
*
mA
mA
(4)
+PS
-PS
NOTES:
3
3
*Same as A/J Models.
1. The specified values are without external trim.
4. The specified values are unloaded.
2. The temperature coefficient (tc) is determined by the
box method using the following formula:
Vmax - Vmin
x 106
tc =
Vnominal x (Tmax-Tmin)
3. The tracking error is the deviation between the
positive and negative output over the operating temp.
range.
VRE405DS REV. A MAY 1996
TYPICAL PERFORMANCE CURVES
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
Temperature oC
VRE405A
Temperature oC
VRE405B
Temperature oC
VRE405C
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
VOUT vs. TEMPERATURE
Temperature oC
VRE405J
Temperature oC
VRE405K
Temperature oC
VRE405L
POSITIVE OUTPUT (TYP)
QUIESCENT CURRENT VS. TEMP
Temperature oC
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
NEGATIVE OUTPUT (TYP)
QUIESCENT CURRENT VS. TEMP
Temperature oC
JUNCTION TEMP. RISE VS. OUTPUT CURRENT
Output Current (mA)
PSRR VS. FREQUENCY
Frequency (Hz)
VRE405DS REV. A MAY 1996
DISCUSSION OF PERFORMANCE
THEORY OF OPERATION
The following discussion refers to the schematic in
figure 2 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
5.000V 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.
The current source provides a closely regulated
zener current, which determines the slope of the
references’ 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
compensation technique is not well suited for wide
temperature ranges.
Thaler Corporation has developed a nonlinear
compensation network of thermistors and resistors
that is used in the VRE series voltage references.
This proprietary network eliminates most of the
nonlinearity in the voltage vs. temperature function.
By 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 VRE405 reference has it’s ground terminal
brought out on two pins (pin 6 and 7) which are
connected 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 does
not effect performance.
VRE405
FIGURE 2
VRE405DS REV. A MAY 1996
MECHANICAL
FIGURE 3
INCHES
MILLIMETER
INCHES
MILLIMETER
DIM
MIN
MAX
MIN
MAX
DIM
MIN
MAX
MIN
MAX
A
.114
.136
2.90
3.45
E
.495
.526
12.5
13.3
B
.098
.103
2.48
2.62
E1
.390
.415
9.91
10.5
B1
.047
.056
1.19
1.42
E2
.265
.270
6.73
6.86
C
.103
.118
2.62
3.00
P
.090
.110
2.29
2.79
C1
.009
.020
0.22
0.51
Q
.024
.035
0.61
.890
C2
.054
.062
1.37
1.57
S
.040
.060
1.02
1.52
D
.690
.715
17.5
18.1
D1
.666
.680
16.9
17.2
FIGURE 4
INCHES
MILLIMETER
INCHES
MILLIMETER
DIM
MIN
MAX
MIN
MAX
DIM
MIN
MAX
MIN
MAX
A
.114
.136
2.90
3.45
E
.410
.435
10.4
11.0
B
.018
.027
.460
.690
E1
.390
.415
9.91
10.5
B1
.047
.056
1.19
1.42
E2
.265
.270
6.73
6.86
B2
.097
.103
2.46
2.62
G1
.285
.315
7.24
8.00
C
.009
.020
0.22
0.51
L
.195
.225
4.95
5.72
D
.690
.715
17.5
18.1
P
.090
.110
2.29
2.79
D1
.666
.680
16.9
17.2
Q
.050
.070
1.27
1.79
S
.040
.060
1.02
1.52
VRE405DS REV. A MAY 1996