Little Demon
®
Carbon Composition Molded
OD/OF Series (5% Tol.) OA Series (10%)
OD/OF/OA Series
Discontinuance Notice:
OA series
is not recommended for new de-
signs. The OA series will no longer
be available for new orders after
8-30-14. After this date existing
stock will be sold until depleted.
F e At u r e S
• Molded insulation for high dielectric strength
• Rugged construction
• High surge capabilities
• Comparable to “Mil” RC07, RC20, and RC32 types
• OD/OF Series available in E24 values
• OA Series available in E12 values
Ohmite’s Little Demons are small, reliable carbon
composition resistors with exceptional strength.
They are made tough by a molding process that
combines the terminals, insulation and resistive ele-
ment into an integrated unit. Along with their small
size, Little Demons perform with low noise, dissipate
heat rapidly and offer high temperature stability.
Color codes are readable even after prolonged use
thanks to a very durable coating that resists abra-
sions and chipping normally associated with auto-
matic insertion equipment.
S e r i e S S p e c i F i c At i O n S
Series
OD
OF
OA
Mil-R-11 Type
RC07
RC20
Wattage
0.25
0.50
1.00
Ohms
2.2-5.6M
2.2-20M
2.2-1M
Tolerance
±5%
±5%
±10%
Max. Voltage
250
350
500
Dielectric VAC
500
700
1000
chArActeriSticS
Terminals
Solder-coated copper terminal.
Body
Molded Phenolic
Tolerance
±5% (OD/OF); ±10% (OA)
Derating
Linearly from 100% @ +70°C to 0% @ 130°C
100,000
10,000
Pulse Power (W)
1,000
100
10
1
10
-7
Single Pulse Power Capability
OF
OD
10
-6
10
-5
10
-4
10
-3
10
-2
Pulse width (s)
10
-1
1
DimenSiOnS
1.135"
±0.
12 /
28.83mm
±3
(OA: 1.18" /
30.0mm)
L
D
Series Length max.
OD
OF
OA
0.276 / 7.0
0.406 /10.3
0.591 /15.0
Diam. max.
0.098 / 2.5
0.150 / 3.8
0.236 / 6.0
Lead Dia.
0.024/0.60
0.028/0.70
0.035/0.92
(continued)
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1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
Little Demon
®
Carbon Composition Molded
OD/OF Series (5% Tol.) OA Series (10%)
All resistors are packaged in sealed poly bags with desiccant
to maintain a consistent humidity during storage. If parts are
removed from the protective plastic bag they should be used
as soon as possible or resealed in the plastic bag.
Tape/Reel
OD
OF
Qty./reel
5000
3000
Reel size (mm)
260
260
Qty./carton
40,000 24,000
Gross carton wt. (kg)
12
13
Carton size (m
3
)
0.04
0.04
Ammo Box
OD
OF
0.5mm max.
52.4mm +1.6
-1.4
6mm
±.5
OD/OF/OA Series
pA c k A g i n g
Storage:
Ohmite recommends storing carbon composition
resistors in a controlled environment at a temperature of 5° to
35°C and relative humidity of less than 60%. Inventory should
always be used on a first-in-first-out basis.
280mm
(ref.)
260mm
±5
5.08mm
±.38
1mm max.
275mm
±5
(OD)
455mm
±5
(OF)
Tape width (mm)
52
52
Qty./box
2000
2000
Qty./carton
30,000 30,000
Gross carton wt. (kg)
10
16
Carton size (m3)
0.03
0.05
60mm
±5
(OD)
65mm
±5
(OF)
75mm
±5
L
1
L
2
3.2mm min.
14.5mm
±.5
3mm
L
1
– L
2
= 1mm max.
75mm
±5
60.4mm±1
60.4mm
±1
reSiStOr uSe guiDelineS
Carbon composition resistors are manufactured by extruding
a blend of carbon and organic binders inside a phenolic outer
body. The extrusion is cut to length, leads inserted, cured,
and marked to form a finished resistor. The carbon and binder
mixture is adjusted to produce different resistance values. The
resistors are sorted for 5%, 10%, and 20% tolerance values.
Carbon composition resistors are able to withstand larger
short-term pulses and higher voltages than film resistors and
are virtually impervious to ESD events (Electro-static dis-
charge). Carbon composition resistors are also sensitive to
moisture and, therefore, storage recommendations should be
adhered to. Generally, any moisture absorbed during storage
will be "baked out" during the soldering operation. If the prod-
uct is stored properly the resistance shift during the soldering
operation will be minimal, less than 2% or 3%.
Carbon composition resistors are highly hygroscopic
and
changes in resistance value can occur if too much moisture is
absorbed. For this reason, it is recommended not to use water
or water-soluble solvents to clean these components. Alcohol
or hydrocarbon solvents are recommended for rinsing.
bAke prOceDure
A. Heat Treatment
110°C ±10°C
15 hours
B. Frequency of
heat treatment
1 time only
C. Solder heat test after treatment
Solder
Dip
Type
Temp.
Time
Evaluation
OD
300°C
3 sec within ±3%
OF
350°C
3 sec within ±3%
*Depth of Immersion: 3mm from the resistor
body
D. Cautions
Solderability:
may be affected due to oxidization of lead wire
Resistance value:
some units may not completely recover to
original value.
Soldering heat:
some treated product may have substantial
resistance change during soldering operation. It is recom-
mended that parts be tested to evaluate soldering heat
effects.
O r D e r i n g i n F O r m At i O n
• OD/OF Series available in E24 values
• OA Series available in E12 values
Tape & reel
RoHS compliant
optional
O D 6 8 3 J E
-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
1-866-9-OHMITE • Int’l 1-847-258-0300 • Fax 1-847-574-7522 • www.ohmite.com • info@ohmite.com
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