Discontinuance Notice: OA series
OD/OF/OA Series
is not recommended for new de-
signs. The OA series will no longer
Little Demon Carbon Composition Molded
be available for new orders after
OD/OF Series (5% Tol.) OA Series (10%)
8-30-14. After this date existing
stock will be sold until depleted.
FeA tureS
Ohmites Little Demons are small, reliable carbon
composition resistors with exceptional strength.
Molded insulation for high dielectric strength
They are made tough by a molding process that
Rugged construction
combines the terminals, insulation and resistive ele-
High surge capabilities
ment into an integrated unit. Along with their small
size, Little Demons perform with low noise, dissipate
Comparable to Mil RC07, RC20, and RC32 types
heat rapidly and offer high temperature stability.
OD/OF Series available in E24 values
Color codes are readable even after prolonged use
OA Series available in E12 values
thanks to a very durable coating that resists abra-
sions and chipping normally associated with auto-
matic insertion equipment.
SerieS SpeciFicA tiOnS
Series Wattage Ohms Tolerance Max. Voltage Dielectric VAC
OD 0.25 2.2-5.6M 5% 250 500
OF 0.50 2.2-20M 5% 350 700
OA 1.00 2.2-1M 10% 500 1000
chArActeriSticS
100,000
Terminals Solder-coated copper terminal.
Single Pulse Power Capability
Body Molded Phenolic
10,000
Tolerance 5% (OD/OF); 10% (OA)
OF
1,000
OD
Derating Linearly from 100% @ +70C to 0% @ 130C
100
10
1
-7 -6 -5 -4 -3 -2 -1
10 10 10 10 10 10 10 1
Pulse width (s)
DimenSiOnS
Series Length max. Diam. max. Lead Dia.
1.135" 0.12 / 28.83mm 3
D
L
(OA: 1.18" / 30.0mm)
OD 0.276 / 7.0 0.098 / 2.5 0.024/0.60
OF 0.406 /10.3 0.150 / 3.8 0.028/0.70
OA 0.591 /15.0 0.236 / 6.0 0.035/0.92
(continued)
1-866-9-OHMITE Intl 1-847-258-0300 Fax 1-847-574-7522 www.ohmite.com info@ohmite.com 93
Pulse Power (W)75mm 5
OD/OF/OA Series
Little Demon Carbon Composition Molded
OD/OF Series (5% Tol.) OA Series (10%)
p AckAging
All resistors are packaged in sealed poly bags with desiccant Storage: Ohmite recommends storing carbon composition
to maintain a consistent humidity during storage. If parts are resistors in a controlled environment at a temperature of 5 to
removed from the protective plastic bag they should be used 35C and relative humidity of less than 60%. Inventor y should
as soon as possible or resealed in the plastic bag. always be used on a first-in-first-out basis.
Tape/Reel OD OF
0.5mm max. 6mm .5
Qty./reel 5000 3000
+1.6
52.4mm
Reel size (mm) 260 260
-1.4
Qty./carton 40,000 24,000 260mm
Gross carton wt. (kg) 12 13 5
3
Carton size (m ) 0.04 0.04
275mm 5 (OD)
5.08mm .38
455mm 5 (OF)
Ammo Box OD OF
1mm max.
Tape width (mm) 52 52
Qty./box 2000 2000
60mm 5 (OD)
14.5mm .5
Qty./carton 30,000 30,000
65mm 5 (OF)
Gross carton wt. (kg) 10 16
Carton size (m3) 0.03 0.05
L L 3.2mm min.
3mm
1 2
75mm 5
L L = 1mm max.
1 2
60.4mm1
60.4mm 1
reSiStOr uSe guiDelineS
Carbon composition resistors are manufactured by extruding moisture and, therefore, storage recommendations should be
a blend of carbon and organic binders inside a phenolic outer adhered to. Generally, any moisture absorbed during storage
body. The extrusion is cut to length, leads inserted, cured, will bebaked ou during the soldering operation. If the prod-
and marked to form a finished resistor. The carbon and binder uct is stored properly the resistance shift during the soldering
mixture is adjusted to produce different resistance values. The operation will be minimal, less than 2% or 3%.
resistors are sorted for 5%, 10%, and 20% tolerance values. Carbon composition resistors are highly hygroscopic and
Carbon composition resistors are able to withstand larger changes in resistance value can occur if too much moisture is
short-term pulses and higher voltages than film resistors and absorbed. For this reason, it is recommended not to use water
are virtually imper vious to ESD events (Electro-static dis- or water-soluble solvents to clean these components. Alcohol
charge). Carbon composition resistors are also sensitive to or hydrocarbon solvents are recommended for rinsing.
bAke prOceDure
A. Heat Treatment C. Solder heat test after treatment D. Cautions
110C 10C Solder Dip Solderability: may be affected due to oxidization of lead wire
15 hours Type Temp. Time Evaluation
Resistance value: some units may not completely recover to
B. Frequency of OD 300C 3 sec within 3% original value.
heat treatment
OF 350C 3 sec within 3% Soldering heat: some treated product may have substantial
1 time only resistance change during soldering operation. It is recom-
*Depth of Immersion: 3mm from the resistor
mended that parts be tested to evaluate soldering heat
body
effects.
OrDering inFOrmA tiOn
OD/OF Series available in E24 values
Tape & reel
OA Series available in E12 values RoHS compliant optional
OD683JE -TR
Series Ohms Tolerance
OD
68G= 6.8 OD, OF:J=5%
OF 680=68 OA: K = 10%
OA
681 = 680
682 = 6,800
683 = 68,000
684 = 680,000
94 1-866-9-OHMITE Intl 1-847-258-0300 Fax 1-847-574-7522 www.ohmite.com info@ohmite.com
280mm
(ref.)