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• All specifications are subject to change without notice.
Varistors(SrTiO3)
For Micro-motors
VAR-18 Series
Ring varistors are used in a wide range of applications from micro
motor noise absorption to the protection of circuit contacts.
TDK has greatly improved the electrical and physical perfor-
mances of these varistors to meet the latest demands. This varis-
tor line covers the traditional shapes and dimensions as well as the
more varied and specialized applications.
FEATURES
ELECTRICAL PERFORMANCES
• The temperature characteristics of the varistor voltage (E
10
value) are positive. This prevents the varistor voltage from
decreasing at high temperatures and from large currents flowing
through the varistor. Therefore, these varistors remove design
obstacles by eliminating the need for setting the room
temperature varistor voltage (E
10 value) higher—a measure that
compromises noise reduction levels.
• Furthermore, the VAR-18 series has also eliminated the problem
of the noise level being amplified at low-temperatures and
having a negative impact on the life of the motor.
• Because the VAR-18 series has the same large capacitance as
the conventional varistors, it has excellent functions to eliminate
and control motor noise in high frequency bands.
PHYSICAL PERFORMANCES
• Because copper electrodes are used and the heat resistance of
the ceramic elements has been improved, there is no concern
for electrode erosion or thermal crack even at the higher
soldering temperatures that are used in lead-free soldering.
• The ceramic element has excellent flexure strength as is
suitable for automatic motor assembly.
PRODUCT LINEUP
• The varistors in this series come in a wide range of dimensions
and so can be accurately used for almost all motors.
• This lineup includes side-surface electrode varistors that can be
used with ultra-compact micro motors.
VARISTOR VOLTAGE TEMPERATURE CHARACTERISTICS
PRODUCT IDENTFICATIONS
(1) Series name
(2) Outer diameter
080: ø8mm
107: ø10.7mm
(3) Varistor voltage
053: 5.3V
157: 15.7V
(4) Varistor voltage tolerance
M: ±20%
(5) Number of electrodes
3, 5, 7
(6) Electrode location
P: Plane
S: Side
(7)TDK classification
PERFORMANCES
Conformity to RoHS Directive
–40 –20
0
20 40 60 80
20
10
0
–10
–20
Temperature(°C)
VAR-18
∆E10(%)
VAR-18
–
(1) (2) (3) (4) (5) (6) (7)
Operating temperature range –25 to +85°C
Pulse resistance
[DC.60V, ON-OFF: 50 cycles]
∆E10,∆α10±15%
Moisture resistance
[60±2°C, 90 to 95(%)RH, 240 hours]
∆E10,∆α10±10%
Soldering heat resistance [320°C, 3 seconds] ∆E10,∆α10±10%
Flexure strength 9.8N min.
Electrode tensile strength 14.7N min.
• Conformity to RoHS Directive: This means that, in conformity with EU Directive 2002/95/EC, lead, cadmium, mercury, hexavalent chromium, and specific
bromine-based flame retardants, PBB and PBDE, have not been used, except for exempted applications.
