T491B155K025AS Kemet, T491B155K025AS Datasheet - Page 7

• Manufacturer Part Number: T491B155K025AS
• Description: CAPACITOR TANT 1.5UF 25V 10% SMD
• Manufacturer: Kemet
• Series: T491r
• Type: Moldedr

Specifications of T491B155K025AS

• Capacitance: 1.5µF
• Voltage - Rated: 25V
• Tolerance: ±10%
• Esr (equivalent Series Resistance): 5.000 Ohm
• Operating Temperature: -55°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 1210 (3528 Metric)
• Size / Dimension: 0.138" L x 0.110" W (3.50mm x 2.80mm)
• Height: 0.075" (1.90mm)
• Manufacturer Size Code: B
• Features: General Purpose
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Lead Spacing: -
• Other names: 399-1625-2

• –55 °C to +125 °C
KEMET solid tantalum capacitors are identified by
the initial “T,” followed by a unique “Series” num-
ber; for example, T491, T492, etc. Each Series
denotes a general physical form and type of
encapsulation, as well as limits on dimensions and
certain electrical characteristics under standard
conditions of 25°C, 50% relative humidity, and one
atmosphere pressure. Specific requirements are
set forth in the respective Product Series in this
catalog. All series are 100% screened for leakage,
capacitance, dissipation factor, and ESR. All
Series are inspected to electrical limits using a
minimum .1% AQL sampling plan, according to
the Military Standard MIL-STD-105, even after
100% testing. This sampling plan, to the best of
KEMET Electronics’ knowledge, meets or exceeds
the generally accepted industry standard for simi-
lar products. KEMET capacitors may also be sup-
plied, with prior agreement, to meet specifications
with requirements differing from those of KEMET cat-
alogs.
Solid tantalum capacitors are usually applied in
circuits where the AC component is small com-
pared to the DC component. Typical uses known
to KEMET Electronics include blocking, by-pass-
ing, decoupling, and filtering. They are also used in
timing circuits. General purpose devices are rec-
ommended to have an external series resistance of
0.1 /volt to reduce the failure due to surge cur-
rent. Newer devices designed for power applica-
tions (T495, T5XX), are built to eliminate this series
resistance requirement. Because tantalum capaci-
tors can experience scintillation (self-healing) in
their life, the circuit impedence should not exceed
100K
degrade leakage.
• –55 °C to +125 °C
Voltage derating is specified in Section 5.
Performance characteristics over this temperature
range are presented within the following sections.
Tantalum capacitors do not lose capacitance from
the “de-forming” effect as do liquid-electrolytic
capacitors. Storage at high temperature may
cause a small, temporary increase in leakage cur-
rent (measured under standard conditions), but the
original value is usually restored within a few min-
utes after application of rated voltage.
Tantalum chips are not hermetically sealed, there-
fore they do exhibit reversible changes in parame-
ters with respect to relative humidity (RH).
Capacitance increases with increasing humidity.
The limiting change, reached upon establishment
©KEMET Electronics Corporation, P.O. Box 5928, Greenville, S.C. 29606, [phone]
or this will circumvent the scintillation and
SOLID TANTALUM CHIP CAPACITORS
of equilibrium with the environment, is approxi-
mately -5% to +12% over the range from 25% to
95% RH, referred to the standard 50% RH. The
amount of change is dependent upon size (capaci-
tance and voltage rating, ie: CV product); small
sizes might change no more than ±5%.
Equilibrium at such extremes is seldom attained by
plastic-cased capacitors, and the change in
capacitance is consequently less. The rate of
response to humidity changes increases with
increasing temperature. Dissipation factor and
ESR also increase with increasing RH.
DC leakage current may rise upon exposure to a
combination of high temperature and high humidi-
ty, but is normally restored by voltage conditioning
under standard conditions. The increase will be
greater than that experienced under temperature
influence alone because of conduction through
absorbed water.
Tantalum chips may be affected by absorption of
water on external insulating surfaces.The water
film may also attract a layer of dust from the air,
increasing the effect. The most sensitive parame-
ter is leakage current.
Refer to part number tables for available capaci-
tance ratings and tolerances by series.
Capacitance is measured at 120 Hz, up to 1.0
volt rms maximum and up to 2.5 volts DC maximum, at
+25°C.DC bias causes only a small reduction in capaci-
tance, up to about 2% when full rated voltage is applied.
DC bias is not commonly used at room temperature, but
is more commonly used at elevated temperatures.
Capacitance decreases with increasing frequency.
Capacitance increases with increasing temperature.
+20%
+10%
0.1 µF to 1000 µF
-10%
-20%
0
-80
-60
-40
-20
Operating Temperature— C
0
+20
+40
+60
+80 +100 +120
5