ETC REF101

REF101
®
Precision
VOLTAGE REFERENCE
FEATURES
APPLICATIONS
● +10.00V OUTPUT
● HIGH ACCURACY: ±0.005V
● VERY LOW DRIFT: 1ppm/°C max
● PRECISION CALIBRATED VOLTAGE
STANDARD
● TRANSDUCER EXCITATION
● D/A AND A/D CONVERTER REFERENCE
● PRECISION CURRENT REFERENCE
● EXCELLENT STABILITY: 50ppm/1000hrs
● LOW NOISE: 6µVp-p typ, 0.1Hz to 10Hz
● ACCURATE COMPARATOR THRESHOLD
REFERENCE
● WIDE SUPPLY RANGE: Up to 35V
● LOW QUIESCENT CURRENT: 6mA max
● USEFUL MATCHED RESISTOR PAIR
INCLUDED
● DIGITAL VOLTMETERS
● TEST EQUIPMENT
DESCRIPTION
The REF101 is a precision voltage reference which
provides a +10.00V output. The drift is laser-trimmed
to 1ppm/°C max (KM grade) over the full specification range. This is in contrast to some references
which guarantee drift over a limited portion of their
specification temperature range. The REF101 achieves
its precision without a heater. This results in low
quiescent current (4.5mA typ), fast warm-up (1ms to
0.1%), excellent stability (50ppm/1000hrs typ), and
low noise (25µVp-p max, 0.1Hz to 10Hz).
The output can be adjusted with minimal effect on
drift or stability. Additionally, the REF101 contains a
matched pair of user-accessible precision 20kΩ resistors which are useful in a variety of applications.
Single supply operation over 13.5V to 35V supply
range and excellent overall specifications make the
REF101 an ideal choice for the most demanding
applications such as precision system standards, D/A
and A/D references, transducer excitation etc.
International Airport Industrial Park • Mailing Address: PO Box 11400
Tel: (520) 746-1111 • Twx: 910-952-1111 • Cable: BBRCORP •
©
1982 Burr-Brown Corporation
R4
165kΩ
VTRIM
2
R2
7kΩ
R1
12kΩ
7
A1
VZ
5
3
+VCC
VOUT
6
R3
2kΩ
Feedback
20kΩ
8
DZ1
RA
20kΩ
4
1
Common
RB
• Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd. • Tucson, AZ 85706
Telex: 066-6491 • FAX: (520) 889-1510 • Immediate Product Info: (800) 548-6132
PDS-485D
Printed in U.S.A. October, 1993
SPECIFICATIONS
ELECTRICAL
At TA = +25°C and +15VDC power supply, unless otherwise noted.
REF101JM, KM, RM, SM
PARAMETER
OUTPUT VOLTAGE
Initial
Trim Range(1)
vs Temperature(2)
KM
JM
SM
RM
vs Supply (line regulation)
vs Output Current
(load regulation)
vs Time
CONDITIONS
MIN
TYP
MAX
UNITS
TA = +25°C
9.995
–0.100
10.000
10.005
+0.250
V
V
1
2
3
6
0.002
ppm/°C
ppm/°C
ppm/°C
ppm/°C
%/V
0°C to +70°C
0°C to +70°C
–55°C to +125°C
–55°C to +125°C
VCC = 13.5 to 35V
0.001
IL = 0 to ±10mA
TA = +25°C
0.001
50
0.002
%/mA
ppm/1000hrs
6
25
µVp-p
NOISE
0.1Hz to 10Hz
OUTPUT CURRENT
Source or Sink
±10
INPUT VOLTAGE RANGE
mA
13.5
QUIESCENT CURRENT
IOUT = 0
4.5
WARM-UP TIME
To 0.1%
10
UNCOMMITTED RESISTORS
Resistance
Match
TCR
TCR Tracking
V
6
mA
µs
20
±0.01
50
2
TEMPERATURE RANGE
Specification
JM, KM
RM, SM
Operating
JM, KM
RM, SM
Storage
35
kΩ
%
ppm/°C
ppm/°C
±0.05
0
–55
+70
+125
°C
°C
–25
–55
–65
+85
+125
+125
°C
°C
°C
NOTES : (1) Triming the offset voltage will affect the drift slightly. See Installation and Operating Instructions for details. (2) The “box method” is used to specify output
voltage drift vs temperature. See the Discussion of Performance section.
ORDERING INFORMATION
MODEL
REF101JM
REF101KM
REF101RM
REF101SM
PIN CONFIGURATION
PACKAGE
TEMPERATURE
RANGE
MAX DRIFT
(ppm/°C)
Metal
Metal
Metal
Metal
0°C to +70°C
0°C to +70°C
–55°C to +125°C
–55°C to +125°C
2
1
6
3
TO-99
TO-99
TO-99
TO-99
Top View
TO-99
Tab
8
20kΩ
RA
20kΩ
RB 1
7
+VCC
7kΩ
165kΩ
PACKAGE INFORMATION
MODEL
PACKAGE
REF101JM
REF101KM
REF101RM
REF101SM
Metal
Metal
Metal
Metal
TO-99
TO-99
TO-99
TO-99
VTRIM
PACKAGE DRAWING
NUMBER(1)
2
001
001
001
001
6
12kΩ
6.3V
VZ 3
+10V
5
VOUT
NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix D of Burr-Brown IC Data Book.
4
Common
ABSOLUTE MAXIMUM RATINGS
20kΩ
Input Voltage ....................................................................................... 40V
Power Dissipation at +25°C .......................................................... 200mW
Operating Temperature Range
JM, KM ......................................................................... –25°C to +85°C
RM, SM ...................................................................... –55°C to +125°C
Storage Temperature Range ......................................... –65°C to +125°C
Lead Temperature (soldering, 10s) ............................................... +300°C
Short-Circuit Protection at +25°C
To Common or +15VDC ...................................................... Continuous
®
REF101
Feedback
2
Optional
Voltage
Trim
NOISE TEST CIRCUIT
OPTIONAL OUTPUT VOLTAGE
FINE ADJUSTMENT CIRCUIT
+VCC
2kΩ
20Ω
The TCR of RS can effect
VOUT drift if RS is made small.
1µF
Tantalum
8kΩ
100µF
7
6 Feedback
OPA27
DUT
2µF
Oscilloscope
REF101
5
2
15.8kΩ
Gain = 100V/V
f3dB = 0.1Hz and 10Hz
VOUT
RS(1)
VTRIM
4
20kΩ
Output
Voltage
Adjust
+10V
NOTE: (1) See Output Voltage Adjustment vs RS Curve.
TYPICAL PERFORMANCE CURVES
At TA = +25°C and +15VDC power supply, unless otherwise noted.
TYPICAL HEATED ZENER NOISE
6
6
4
4
Noise Voltage (µV)
Noise Voltage (µV)
TYPICAL REF101 NOISE
2
0
–2
–4
–6
2
0
–2
–4
–6
Low Frequency Noise
(see Noise Test Ciruit)
Low Frequency Noise
(see Noise Test Ciruit)
POWER TURN-ON RESPONSE
TYPICAL BANDGAP REFERENCE NOISE
20
Error From Final Value (mV)
Noise Voltage (µV)
6
4
2
0
–2
–4
15
10
5
0
–5
–10
–15
–6
–20
Power Turn-On
Low Frequency Noise
(see Noise Test Ciruit)
®
3
REF101
TYPICAL PERFORMANCE CURVES (CONT)
At TA = +25°C and +15VDC power supply, unless otherwise noted.
RESPONSE TO THERMAL SHOCK
POWER SUPPLY REJECTION vs FREQUENCY
100
Power Supply Rejection (dB)
Output Voltage Change (µV)
400
200
0
–200
Device immersed in +70°C fluorinert bath.
TA =
+25°C
–400
TA = +70°C
0
90
80
70
60
50
40
30
5
10
15
20
100
1k
Time (s)
LOAD REGULATION vs TEMPERATURE
100k
QUIESCENT CURRENT vs TEMPERATURE
4
5
3
Negative Current (Sink)
Quiescent Current (mA)
Load Regulation (ppm/mA)
10k
Frequency (Hz)
2
1
0
Positive Current (Sink)
–1
–2
4
3
2
–3
–4
–75
–50
–25
0
25
50
75
100
125
–50
–25
Temperature (°C)
100
See Optional Output Voltage
Fine Adjustment Circuit
Junction Temperature Rise
Above Ambient (°C)
Output Voltage Adjustment (mV)
25
50
75
100
125
JUNCTION TEMPERATURE RISE vs OUTPUT CURRENT
OUTPUT VOLTAGE ADJUSTMENT vs RS
10k
1k
Voltage Increase
100
Voltage Decrease
10
0
Temperature (°C)
Max. Temp. Rise for +85°C Ambient
80
VCC = 35V
V
V CC
Max. Temp. Rise for
+125°C Ambient
60
= 30
V CC =
25V
V
40
V CC = 20
20
VCC = 15V
0
1
10k
100k
1M
10M
0
100M
®
REF101
2
4
6
Output Current (mA)
RS (Ω)
4
8
10
THEORY OF OPERATION
temperature range of 0°C to +70°C. The “box” height (V1 to
V2) is 700µV and upper bound and lower bound voltages are
a maximum of 700µV away from the voltage at +25°C.
The following discussion refers to the diagram on the first
page.
In operation, approximately 6.3V is applied to the
noninverting input of op amp A1 by zener diode DZ1. This
voltage is amplified by A1 to produce the 10.00V output.
The gain is determined by R1 and R2: G = (R1 + R2)/R1.
R1 and R2 are actively laser-trimmed to produce an exact
10.00V output. The zener operating current is derived from
the regulated output voltage through R3. This feedback
arrangement provides closely regulated zener current. R3 is
actively laser-trimmed to set the zener current to a level
which results in low drift at the output of A1. The adjustment
of output voltage and zener current is interactive and several
iterations may be used to achieve the desired results. R4
allows user-trimming of the output voltage by providing for
a small external adjustment of amplifier gain. Since the TCR
of R4 closely matches the TCR of the gain setting resistors,
the voltage trim has minimal effect on the drift of the
reference.
VUPPER BOUND
+10.0007
V1
Output Voltage (V)
Typical Drift
p
1p
VLOWER BOUND
0
(TLOW)
25
70
(THIGH)
Temperature (°C)
FIGURE 1. REF101KM Output Voltage Drift.
INSTALLATION AND
OPERATING INSTRUCTIONS
The REF101 is designed for applications requiring a precision voltage reference where both the initial value at room
temperature and the drift over temperature are of importance
to the user. Two basic methods of specifying voltage reference drift versus temperature are in common usage in the
industry—the “butterfly method” and the “box method”.
Neither of these methods is entirely satisfactory in cases
where the drift versus temperature is relatively nonlinear as
is the case with most voltage references. The REF101 is
specified with the more commonly used box method. The
“box” is formed by the high and low specification temperatures and a diagonal, the slope of which is equal to the
maximum specified drift.
BASIC CIRCUIT CONNECTION
Figure 2 shows the proper connection of the REF101. To
achieve the specified performance, pay careful attention to
layout. A low resistance star configuration will reduce voltage errors, noise pickup, and noise coupled from the power
supply. Commons should be connected as indicated being
sure to minimize interconnection resistances.
(1)
7
For the REF101, each J and K unit is tested at temperatures
of 0°C, +25°C, +50°C, and +70°C, and each R and S unit is
tested at –55°C, –25°C, 0°C, +25°C, +50°C, +75°C, +100°C
and +125°C. The minimum and maximum test voltages
must meet this condition.
THIGH – TLOW
V2
700µV
Worst-case
> VOUT
for
REF101KM
l
M
na
1K
go
10
Dia REF
for
°C
m/
+9.9993
DISCUSSION OF
PERFORMANCE
(VOUT MAX – VOUT MIN)/10V
+10.0000
6 Feedback
VCC
+
REF101
(2)
(3)
5 VOUT
(1)
1µF
Tantalum
RL1
4
x 106 ≤ drift specification
RL2
RL3
(3)
(1)
This assures the user that the variations of output voltage
that occur as the temperature changes within the specification range TLOW to THIGH will be contained within a box
whose diagonal has a slope equal to the maximum specified
drift. Since the shape of the actual drift curve is not known,
the vertical position of the box is not exactly known either.
It is, however, bounded by VUPPER BOUND and VLOWER
BOUND (see Figure 1).
NOTES: (1) Lead resistance here of up to a few Ωs have negligible effect on
performance. (2) A relatively constant current of approximately 2mA at
50ppm/°C flows in this lead. 1Ω in this lead would introduce about 2mV error
(adjustable to zero) with about 0.1ppm/°C drift at the output. (3) A resistance
of 0.1Ω in series with these leads will cause a 1mV error when the load current
is at its maximum of 10mA. This results in a 0.01% error of 10V.
FIGURE 2. REF101 Basic Circuit Connection.
Figure 1 uses the REF101KM as an example. It has a drift
specification of 1ppm/°C maximum and a specification
®
5
REF101
APPLICATION INFORMATION
OPTIONAL OUTPUT VOLTAGE ADJUSTMENT
Optional output voltage adjustment circuits are shown in
Figures 3 and 4. Trimming the output voltage will change
the voltage drift by approximately 0.01 ppm/°C per mV of
trimmed voltage. In the circuit in Figure 3, any mismatch in
TCR between the two sections of the potentiometer will also
affect drift, but the effect of the ∆TCR is reduced by a factor
of 40 by the internal resistor divider. A high quality potentiometer, with good mechanical stability, such as a cermet,
should be used. The circuit in Figure 3 has a range of
approximately +250mV to –100mV. The circuit in Figure 4
has less range but provides higher resolution. The mismatch
in TCR between RS and the internal resistors can introduce
some slight drift. This effect is minimized if RS is kept
significantly larger than the 165kΩ internal resistor. A TCR
of 100ppm/°C is normally sufficient.
High accuracy, extremely-low drift, and small size make the
REF101 ideal for demanding instrumentation and system
voltage reference applications. Since no heater is required,
low power supply current designs are readily achievable.
Also the REF101 has lower output noise and much faster
warm-up times (1ms to 0.1%) than heated references, permitting high precision without extra power from additional
supplies. It should be considered that operating any integrated circuit at an elevated temperature will reduce its
MTTF.
A variety of application circuits are shown in Figures 5
through 19.
+VCC
+VCC
+
7
OPA27
6
1µF
Tantalum
REF101
7
R
1kΩ
5
VOUT = +10V
C
6 Feedback
5
REF101
100µF
VOUT
fCO =
4
20kΩ
Output
Voltage
Adjust
2 VTRIM
4
+10V
1
=1.6Hz
2π RC
FIGURE 5. Precision Reference with Filtering.
Maximum range (+2.5%, –1%) and minimal degradation of drift.
+15V
FIGURE 3. REF101 Optional Output Voltage Adjustment.
OPA128
+VCC
VOUT 1 = –10V
The TCR of RS can effect
VOUT drift if RS is made small.
+
1µF
Tantalum
+VCC = 15V
–15V
7
6 Feedback
REF101
5 VOUT
1
(1)
RS
2
4
8
VTRIM
20kΩ
Output
Voltage
Adjust
20kΩ
7
20kΩ
+10V
REF101
6
5
VOUT 2 = +10V
4
NOTE: (1) RS typically 4MΩ.
Higher resolution,
reduced range.
See information in Typical
Performance Curves.
FIGURE 6. ±10V Reference.
FIGURE 4. REF101 Optional Output Voltage Fine Adjust.
The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN
assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user’s own risk. Prices and specifications are subject
to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not
authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.
®
REF101
6
+15V
DG187
OPA128
VOUT 1 = +10V
or –10V
OPA128
VOUT 1 = +5V
CMOS
Switch
+VCC = 15V
+VCC = 15V
8
1
7
20kΩ
20kΩ
1
20kΩ
20kΩ
6
6
Logic
VOUT
0
1
+10V
–10V
5
REF101
REF101
Logic Input
7
8
+10V
Auxiliary
Output
5
VOUT 2 = +10V
4
4
FIGURE 9. Digitally-Controlled Bipolar Precision
Reference.
FIGURE 7. +10V and +5V Reference.
+VCC = 55V to 80V
+VCC = 15V to 35V
7
6
7
2
6
REF101
REF101
5
47Ω
2N6551
5
2N3904
VOUT 5 = +50V
7
4
3.3Ω
6
4
REF101
IOUT = 0 to +100mA
Optional Trim
5
VOUT 4 = +40V
7
VOUT = +10V
20kΩ
6
4
REF101
5
FIGURE 10. +10V Reference with Boosted Output Current
to 100mA.
VOUT 3 = +30V
7
6
4
REF101
5
VOUT 2 = +20V
7
6
16kΩ
+VCC = 48V
(Range of 32V to 64V)
4
REF101
2N6591
5
VOUT 1 = +10V
0.1µF
5.6V
7
4
6
VOUT = +10V
REF101
5
FIGURE 8. Stacked References.
4
FIGURE 11. +10V Reference with Input Voltage Boost for
48V Operation.
®
7
REF101
+VCC = 15V
7
+30V
8
2
7
R1
R2
20kΩ
20kΩ
1
6
REF101
Ladder resistor tolerances:
All 10kΩ 0.02%
All 10Ω 1%
5
6
5
REF101
4
4MΩ
100kΩ
10V
4
10Ω
+15V
25kΩ
10kΩ
5V
50Ω
OPA111
IOUT
IOUT = 10V/R
where R = R1||R2.
10Ω
10kΩ
–15V
10kΩ
2V
20Ω
IOUT may be raised up to 10mA
by using external resistors.
10Ω
20kΩ
10kΩ
1V
FIGURE 12. Positive Precision 1mA Current Source.
50Ω
10Ω
25kΩ
R1
5kΩ
VIN
0 to 10V
Zero
Adjust
2
0.5V
IOUT
4mA to
20mA
Siliconex
+15V
+15V
10kΩ
50Ω
7
OPA111
10Ω
3
VN89AB
10kΩ
OPA111
20Ω
1
10Ω
100kΩ
20kΩ
10kΩ
0.1V
+VCC = 15V
8
1
20kΩ
7
20kΩ
50Ω
R2
416.7Ω
Span
Adjust
10Ω
50kΩ
25kΩ
10kΩ
0.05V
6
50Ω
REF101
5
–15V
10Ω
+10V
10kΩ
10kΩ
0.02kΩ
4
20Ω
10Ω
10kΩ
10kΩ
0.01V
FIGURE 13. 4mA to 20mA Precision Current Transmitter.
20Ω
FIGURE 14. Precision Voltage Calibrator.
®
REF101
8
VOUT
4
5
10kΩ
0.2V
–15V
6
–15V
NOTE: Tie all
commons to
one point.
+15V
+VCC = 24V
7
8
7
820Ω
6
1
OPA111
6
5
REF101
+5V
Out
5
REF101
+10V
4
600Ω
600Ω
4
–5V
Out
∆V
600Ω
FIGURE 17. ±5V Reference.
600Ω
+30V
7
8
At 10.00V, the 600Ω bridge requires 16.7mA. An 820Ω resistor
connected directly from the bridge to the positive supply provides the
bulk of the bridge current. The REF101 need only supply an error
current to keep the bridge at 10.00V. Since the REF101 can sink or
source up to 10mA, the circuit shown can tolerate supply variations
of up to 24V, ±8V, or bridge resistance drift from 400Ω to 1400Ω.
1
6
FIGURE 15. +10V Reference with Output Current Boost
Using a Resistor to Drive a 600Ω Bridge.
+20V
4
+10
OPA111
R
R + ∆R
5
REF101
FIGURE 18. +10V and +20V Reference.
RG
0.01µF
+15V
8
1
+VCC
1
20kΩ
20kΩ
REF101
6
VOUT =
2kΩ
13
7
8
10
VOUT
11
∆R X RG
2000R
VFC320
7
30kΩ
14
Gain
Adjust
5
5
4
+0 to 10kHz
Output
3300pF
+15V
–15V
8
7
4
1
±10V
Input
NOTE: “Tame Transducer Bridge Errors with Op Amp Feedback
Control”, EDN, May 26, 1982, Jerald Graeme.
6
REF101
5
FIGURE 16. Linear Bridge Circuit Using Internal Precision
Resistors of the REF101 as the Bridge Completion Network.
4
FIGURE 19. Bipolar Input Voltage-to-Frequency Converter.
®
9
REF101