independent. Also, since the current sources are two-
terminal devices, they can be used equally well as
current sinks. The performance of each section is
individually measured and laser-trimmed to achieve
high accuracy at low cost.
The sections can be pin-strapped for currents of 50µA,
100µA, 200µA, 300µA or 400µA. External circuitry
can be used to obtain virtually any current. These and
many other circuit techniques are shown in the
Applications section of this Data Sheet.
The REF200 is available in plastic 8-pin mini-DIP
and SOIC packages.
I
1
High
8
I
2
High
7
Substrate
6
Mirror
In
5
100µA
100µA
1
I
1
Low
2
I
2
Low
3
Mirror
Common
4
Mirror
Out
International Airport Industrial Park • Mailing Address: PO Box 11400, Tucson, AZ 85734 • Street Address: 6730 S. Tucson Blvd., Tucson, AZ 85706 • Tel: (520) 746-1111 • Twx: 910-952-1111
This integrated circuit can be damaged by ESD. Burr-Brown
recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
NOTE: (1) For detailed drawing and dimension table, please see end of data
sheet, or Appendix C of Burr-Brown IC Data Book. (2) Grade designation “A”
may not be marked. Absence of grade designation indicates A grade.
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.
®
REF200
2
TYPICAL PERFORMANCE CURVES
At T
A
= +25°C, V
S
= +15V, unless otherwise noted.
CURRENT SOURCE
TYPICAL DRIFT vs TEMPERATURE
100.1
100
600
500
CURRENT SOURCE
TEMPERATURE DRIFT DISTRIBUTION
501
454
Distribution of three
production lots —
1284 Current Sources.
99.8
99.7
99.6
99.5
–50
–25
0
25
50
75
100
125
Drift specified by
“box method”
(See text)
85°C
Quantity (Units)
Current (µA)
99.9
400
300
200
117
100
0
0
2
5
5
86
66
30 15
6
0
1
1
10 15 20 25 30 35 40 45 50 55 60 65
Temperature Drift (ppm/°C)
Temperature (°C)
CURRENT SOURCE
OUTPUT CURRENT vs VOLTAGE
CURRENT SOURCE
OUTPUT CURRENT vs VOLTAGE
100.5
100.4
100.3
100.2
101
100.8
100.6
100.4
Current (µA)
100.2
100
99.8
99.6
99.4
99.2
99
0
5
10
15
20
Voltage (V)
25
30
35
40
Current (µA)
100.1
100
99.9
99.8
99.7
99.6
99.5
0
1
2
3
25°C
–55°C
125°C
4
5
Voltage (V)
CURRENT SOURCE
CURRENT NOISE (0.1Hz to 10Hz)
1000
900
CURRENT SOURCE
REVERSE CURRENT vs REVERSE VOLTAGE
Output Current (500pA/div)
800
12kΩ
7V
Reverse Voltage
Circuit Model
5kΩ
Reverse Current (µA)
700
600
500
400
300
200
100
0
Safe Reverse Current
Safe Reverse Voltage
Time (500ms/div)
0
–2
–4
–6
–8
–10
–12
Reverse Voltage (V)
®
3
REF200
TYPICAL PERFORMANCE CURVES
(CONT)
At T
A
= +25°C, V
S
= +15V, unless otherwise noted.
MIRROR GAIN ERROR vs CURRENT
5
4
3
2
Error (%)
1
0
–1
–2
–3
–4
–5
0.1
0.08
Nonlinearity (% of 250µA)
0.06
0.04
0.02
0
–0.02
–0.04
–0.06
–0.08
–0.01
MIRROR TRANSFER NONLINEARITY
Data from Three
Representative Units
(Least-square fit)
V
O
=
1.25V
V
O
= 1V
V
O
= 1.5V
10µA
100µA
Mirror Current (A)
1mA
0
50
100
150
Current (µA)
200
250
MIRROR INPUT VOTAGE/OUTPUT
COMPLIANCE VOLTAGE vs CURRENT
4
3
Input Voltage (V)
2
Input Voltage
Output
Compliance
Voltage
1
0
1µA
10µA
100µA
Current
1mA
10mA
®
REF200
4
APPLICATIONS INFORMATION
The three circuit sections of the REF200 are electrically
isolated from one another using a dielectrically isolated
fabrication process. A substrate connection is provided (pin
6), which is isolated from all circuitry. This pin should be
connected to a defined circuit potential to assure rated DC
performance. The preferred connection is to the most nega-
tive constant potential in your system. In most analog
systems this would be –V
S
. For best AC performance, leave
pin 6 open and leave unused sections unconnected.
Drift performance is specified by the “box method,” as
illustrated in the Current vs Temperature plot of the typical
performance curves. The upper and lower current extremes
measured over temperature define the top and bottom of the
box. The sides are determined by the specified temperature
range of the device. The drift of the unit is the slope of the
diagonal—typically 25ppm/°C from –25°C to +85°C.
If the current sources are subjected to reverse voltage, a
protection diode may be required. A reverse voltage circuit
model of the REF200 is shown in the Reverse Current vs
Reverse Voltage curve. If reverse voltage is limited to less
than 6V
or
reverse current is limited to less than 350µA, no
protection circuitry is required. A parallel diode (Figure 2a)
will protect the device by limiting the reverse voltage across
the current source to approximately 0.7V. In some applica-
tions, a series diode may be preferable (Figure 2b) because
it allows no reverse current. This will, however, reduce the
compliance voltage range by one diode drop.
Applications for the REF200 are limitless. Application Bul-
letin AB-165 shows additional REF200 circuits as well as
other related current source techniques. A collection of
circuits is shown to illustrate some techniques. Also, see
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