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HIN
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ILM
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HIP
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ESISTORS
68 Series 0.020”x0.020”
Spectrum Microwave 68 Series 0.020” x 0.020” Thin-film Chip Resistors are available in both
top-contact and back-contact versions in several resistances and tolerances. Values are available
from 1 ohm to 500 Kohms. Both passivated nichrome and tantalum-nitride resistor versions are
available. Nichrome provides excellent stability and temperature coefficient in hermetic applications
while tantalum-nitride provides superior moisture-resistance for non-hermetic applications.
Electrical Specifications
Parameter
Power Rating
Life
Noise
High Temp Exposure
TCR (68AL, 68BCN)
TCR (68ALT, 68BCR)
Operating voltage
Moisture resistance
Thermal shock
Limit
100 mW
±0.2% max
-35 dB typ
±0.2% max
±50 ppm/°C
-50 to -120 ppm/°C
100 VDC max
±0.5% max
±0.5% max
Test conditions
(derated at 70° to 0 mW @ 150°)
1000 hours @ 125° C
MIL-STD-202 method 308
100 hours at 150° C
-55° to 125° C
-55° to 125° C
MIL-STD-202 method 106
MIL-STD-202 method 107
Typical Configurations
Values below 20 oh ms
Values from 20 to 200 ohms
Values above 200 ohms
0.020
On back--Contact versions, pad without bevel is connected to back side.
0.005
Mechanical Specifications
Substrate
Bond pad metalization
Size
Thickness
Bond pad dimensions
Protective overcoat (passivation)
Back side
Silicon with 1 micron thermal oxide
Gold, 100 microinches
0.021 x .021 ±0.002 (0.53 x 0.53 mm ±0.05 mm)
0.013 ±0.003 (0.33 ±0.07 mm)
0.004 x .004 minimum (0.1 x 0.1 mm)
0.6 microns SiO2 (68AL & 68BCN versions only)
Lapped silicon (68AL, 68ALT), Gold (68BCN, 68BCR)
Tel: 508-485-6350 Fax : 508-485-5168
165 Cedar Hill Street, Marlborough, Ma 01752
www.SpectrumMicrowave.com
Spectrum Microwave
T
HIN
F
ILM
C
HIP
R
ESISTORS
68 Series 0.020”x0.020”
All parts are 100% electrically tested, sample tested per MIL-STD-38534 section 3.4, and
visually inspected to MIL-STD-883 requirements. Chips are supplied in standard 2"x 2"
matrix tray packaging.
Ordering Information
Base Part Code
Value (3 digits plus exponent)
T
olerance Letter
X
B = 0.1%
C = 0.25%
D = 0.5%
F = 1%
G = 2%
J = 5%
K = 10%
M = 20%
68xxx-
68AL (Nichrome top-contact)
68ALT (Tantalum-nitride top-
contact)
68BCN (Nichrome back-contact)
68BCR (Tantalum-nitride back-
contact)
NNNE
(Under 100 ohms, an R indicates the
decimal point location)
Ordering Examples:
68AL-5002F is a 50 kilohm 1% resistor with nichrome metalization.
68ALT-75R0J is a 75 ohm 5% resistor with tantalum-nitride metalization.
68BCR-5R10K is a 5.1 ohm 10% back contact resistor with tantalum-nitride metalization.
Availability and Limitations:
68AL & 68BCN series are available from 2 ohms to 500 kohms.
68ALT & 68BCR series are available from 1 ohm to 250 kohms.
B tolerance is available above 250 ohms.
C tolerance is available above 100 ohms.
D tolerance is available above 50 ohms.
F tolerance is available above 25 ohms.
G tolerance is available above 12 ohms.
J tolerance is available above 5 ohms.
(Specifications subject to change without notice.)
Spectrum Microwave
also manufactures Custom Substrates on a variety of materials, a wide range of Microwave, PIN
Diode Drivers, and Custom Hybrid Circuits. Please contact the factory or your local representative for more information.
