T491B155K025AS Kemet, T491B155K025AS Datasheet - Page 10

• 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

8
X
where:
X
where:
L
C
= 2 fL
= 1 ohm
To understand the many elements of a capaci-
tor, see Figure 8.
A capacitor is a complex impedance consisting of
many series and parallel elements, each adding
to the complexity of the measurement system.
ESL — Represents lead wire and construction
inductance. In most instances (especially in solid
tantalum and monolithic ceramic capacitors) it is
insignificant at the basic measurement frequen-
cies of 120 and 1000 Hz.
f = frequency, Hertz
L = inductance, Henries
f = frequency, Hertz
C = capacitance, Farad
2 fC
ESL
©KEMET Electronics Corporation, P.O. Box 5928, Greenville, S.C. 29606, [phone]
ESR
SOLID TANTALUM CHIP CAPACITORS
C
d
R
C
L
R
d
ESR — Represents the actual ohmic series resis-
tance in series with the capacitance. Lead wires
and capacitor electrodes are contributing sources.
R
can reach 50,000 megohms in a tantalum capaci-
tor. It can exceed 10
ics and in film capacitors.
R
absorption and molecular polarization. It becomes
very significant in high frequency measurements
and applications. Its value varies with frequency.
C
solid tantalum capacitor which typically equates to
1-2% of the applied voltage.
As frequency increases, X
according to its equation above. There is unavoid-
able inductance as well as resistance in all capaci-
tors, and at some point in frequency, the reac-
tance ceases to be capacitive and becomes
inductive. This frequency is called the self-reso-
nant point. In solid tantalum capacitors, the reso-
nance is damped by the ESR, and a smooth,
rather than abrupt, transition from capacitive to
inductive reactance follows.
Typical ESR/Z frequency response curves are
shown in Figures 9a and 9b. These curves are
for selected ratings and represent typical T491
Series performance. Maximum limits for 100 kHz
ESR are listed in the part number tables for
each series. Note that the T494 Series offers low
ESR and the T495 Series is specially designed
for very low ESR performance. Refer to page 31
for more information. See also KEMET’s T510
Series low ESR ratings on page 40.
L
d
d
— Capacitor Leakage Resistance. Typically it
— The dielectric loss contributed by dielectric
— The inherent dielectric absorption of the
12
ohms in monolithic ceram-
C
continues to decrease