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Zetex Semiconductors |
PRECISION 2.45 VOLT
VOLTAGE REFERENCE
ISSUE 3 — MARCH 1998
DEVICE DESCRIPTION
The ZRA245 uses a bandgap circuit design
to achieve a precision voltage reference of
2.45 volts. The device is available in small
outline surface mount packages, ideal for
applications where space saving is
important.
The ZRA245 design provides a stable voltage
without an external capacitor and is stable
with capacitive loads. The ZRA245 is
recommended for operation between 2mA
and 120mA.
SCHEMATIC DIAGRAM
VR
ZRA245
FEATURES
• Small outline SOT23, SO8 and TO92
style package
• No stabilising capacitor required
• Typical TC 15ppm/°C
• Typical slope resistance 0.26Ω
• ± 3% , 2% and 1% tolerance
• Industrial temperature range
• Operating current 2mA to 120mA
APPLICATIONS
• Battery powered and portable
equipment.
• Metering and measurement systems.
• Instrumentation.
• Test equipment.
• Data acquisition systems.
• Precision power supplies.
1.25VREF
Gnd
4-227
ZRA245
ABSOLUTE MAXIMUM RATING
Reverse Current
200mA
Forward Current
25mA
Operating Temperature -40 to 85°C
Storage Temperature
-55 to 125°C
Power Dissipation (Tamb=25°C)
SOT23
330mW
E-Line, 3 pin (TO92)
500mW
E-Line, 2 pin (TO92)
500mW
SO8
625mW
ELECTRICAL CHARACTERISTICS
TEST CONDITIONS (Unless otherwise stated) Tamb=25°C
SYMBOL PARAMETER
CONDITIONS
LIMITS
TOL. UNITS
%
MIN TYP MAX
VR
Reverse Breakdown Voltage IR=5mA
2.43 2.45 2.47 1
V
2.40 2.45 2.50 2
2.38 2.45 2.52 3
IMIN Minimum Operating Current
IR Recommended Operating
Current
2 mA
2 120 mA
TC †
RS §
ZR
EN
Average Reverse Breakdown
Voltage Temp. Co.
Slope Resistance
IR(min) to
IR(max)
Reverse Dynamic Impedance
IR = 5mA
f = 100Hz
IAC= 0.1 IR
Wideband Noise Voltage
IR= 5mA
f = 10Hz to
10kHz
15 50
0.26 0.5
0.28 1
65
ppm/°C
Ω
Ω
µV(rms)
†
TC
=
(VR(max)−VR(min)) x 1000000
VR x (T(max)−T(min))
Note: VR(max) - VR(min) is the maximum
deviation in reference voltage measured
over the full operating temperature
range.
§
RS
=
VR
Change(IR (min) to IR
IR (max) − IR (min)
(max))
4-228
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