SCHEMATIC DIAGRAM
PRECISION 1.25 VOLT
MICROPOWER VOLTAGE REFERENCE
ISSUE 2 - MARCH 1998
ZREF12
V
R
G
nd
DEVICE DESCRIPTION
The ZREF12 uses a bandgap circuit design to
achieve a precision micropower voltage
reference of 1.24 volts. The device is
available in a small outline surface mount
package, ideal for applications where space
saving is important, as well as packages for
through hole requirements.
The ZREF12 design provides a stable voltage
without an external capacitor and is stable
with capacitive loads. The ZREF12 is
recommended for operation between 50
A
and 5mA and so is ideally suited to low
power and battery powered applications.
Excellent performance is maintained to an
absolute maximum of 25mA, however the
rugged design and 20 volt processing allows
the reference to withstand transient effects
and currents up to 200mA. Superior
switching capability allows the device to
reach stable operating conditions in only a
few microseconds.
FEATURES
Small outline SO8 and TO92 style
packages
No stabilising capacitor required
Typical T
C
30ppm/C
Typical slope resistance 0.65
1% tolerance
Industrial temperature range (Military
temperature range available on request)
Operating current 50
A to 5mA
Transient response, stable in less than
10
s
Alternative package options and
tolerances available
APPLICATIONS
Battery powered and portable
equipment.
Metering and measurement systems.
Instrumentation.
Precision power supplies.
Test equipment.
Data acquisition systems
4-267
ABSOLUTE MAXIMUM RATING
Reverse Current
25mA
Forward Current
25mA
Operating Temperature
-40 to 85C
Storage Temperature
-55 to 125C
Power Dissipation (T
amb
=25C)
E-Line, 3 pin (TO92)
500mW
E-Line, 2 pin (TO92)
500mW
SO8
625mW
Reverse Characteristics
Reverse Voltage (V)
Re
ver
s
e
Cu
rre
n
t (
A)
0
0.2
0.4
0.8
1.4
0.6
1.0
0
10
20
30
40
50
60
T
A
=25C
T
A
=-
40C
T
A
=85C
1.2
ZREF12
ELECTRICAL CHARACTERISTICS
TEST CONDITIONS (Unless otherwise stated) T
amb
=25C
SYMBOL PARAMETER
CONDITIONS
LIMITS
TOL.
%
UNITS
MIN
TYP MAX
V
R
Reverse Breakdown
Voltage
I
R
=150
A
1.228
1.24 1.252
1
V
I
MIN
Minimum Operating
Current
30
50
A
I
R
Recommended Operating
Current
0.05
5
mA
T
C
Average Reverse Breakdown
Voltage Temp. Co.
I
R(min)
to
I
R(max)
30
90
ppm/C
R
S
Slope Resistance
0.65 2
Z
R
Reverse Dynamic
Impedance
I
R
= 1mA
f = 100Hz
I
AC
= 0.1 I
R
0.5
1
E
N
Wideband Noise Voltage
I
R
= 150
A
f = 100Hz to
10kHz
60
V(rms)
T
C
=
(
V
R
(
max
)
-
V
R
(
min
)
)
x 1000000
V
R
x
(
T
(
max
)
-
T
(
min
)
)
Note: V
R(max)
- V
R(min)
is the maximum
deviation in reference voltage measured
over the full operating temperature
range.
R
S
=
V
R
Change
(
I
R
(
min
)
to I
R
(
max
)
)
I
R
(
max
)
-
I
R
(
min
)
4-268
SO8 Package
Suffix N8
Top
View
E-Line, 3 pin,Rev Package Suffix R
Bottom
View
Pin 3 floating or connected to pin 1
E-Line, 2 pin Package Suffix Y
Bottom
View
CONNECTION DIAGRAMS
Part No
Tol%
Package
Partmark
ZREF12
1
E-Line
ZREF12
ZREF12Z
1
E-Line *
ZREF12
ZREF12D
1
SO8
ZREF12
* E-Line 3 pin Reversed
E-Line 2 pin
ORDERING INFORMATION
ZREF12
4-270
PDF 
ZIP