THIN FILM CHIP RESISTORS
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.
Spectrum Microwave
Tel: 508-485-6350 Fax : 508-485-5168
165 Cedar Hill Street, Marlborough, Ma 01752
www.SpectrumMicrowave.com
Electrical Specifications
Parameter Limit Test conditions
Power Rating 100 mW (derated at 70° to 0 mW @ 150°)
Life ±0.2% max 1000 hours @ 125° C
Noise -35 dB typ MIL-STD-202 method 308
High Temp Exposure ±0.2% max 100 hours at 150° C
TCR (68AL, 68BCN) ±50 ppm/°C -55° to 125° C
TCR (68ALT, 68BCR) -50 to -120 ppm/°C -55° to 125° C
Operating voltage 100 VDC max
Moisture resistance ±0.5% max MIL-STD-202 method 106
Thermal shock ±0.5% max MIL-STD-202 method 107
Values from 20 to 200 ohmsValues below 20 oh ms Values above 200 ohms
Mechanical Specifications
Substrate Silicon with 1 micron thermal oxide
Bond pad metalization Gold, 100 microinches
Size 0.021 x .021 ±0.002 (0.53 x 0.53 mm ±0.05 mm)
Thickness 0.013 ±0.003 (0.33 ±0.07 mm)
Bond pad dimensions 0.004 x .004 minimum (0.1 x 0.1 mm)
Protective overcoat (passivation) 0.6 microns SiO2 (68AL & 68BCN versions only)
Back side Lapped silicon (68AL, 68ALT), Gold (68BCN, 68BCR)
Typical Configurations
On back--Contact versions, pad without bevel is connected to back side. 0.005
0.020
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.
(Specifications subject to change without notice.)
THIN FILM CHIP RESISTORS
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.
Base Part Code
68xxx-
68AL (Nichrome top-contact)
68ALT (Tantalum-nitride top-
contact)
68BCN (Nichrome back-contact)
68BCR (Tantalum-nitride back-
contact)
Value (3 digits plus exponent)
NNNE
(Under 100 ohms, an R indicates the
decimal point location)
Tolerance Letter
X
B = 0.1%
C = 0.25%
D = 0.5%
F = 1%
G = 2%
J = 5%
K = 10%
M = 20%
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.
Ordering Information
