ITT - Index of

TYPE TAG
Plastic Encapsulated Tantalum Capacitors
Definitions and Ratings
RATED CAPACITANCE -
60 cycles and +25°C.
Value measured at
CAPACITANCE TOLERANCE - Variation of
actual value from nominal rated value in per
cent (%).
RATED DC VOLTAGE - Listed rating in volts
DC at a surface temperature of +40°C.
CONTINUOUS MAXIMUM VOLTAGE-Highest
DC voltage which can be applied to capacitor.
Max voltage equals rated voltage up to +85°C
ambient temperature.
SURGE VOLTAGE-Maximum voltage to which
capaCitor may be subjected 5 times per hour
for one minute. Maximum value is 1.15 times
the rated voltage. Capacitors should not be
used in electrical circuits where the capacitor
is regularly charged and discharged to the
peak of the surge voltage.
REVERSE VOLTAGE-Not to exceed 0.5 Reverse
voltage higher than this limit can be
handled by connecting 2 capacitors in antiseries
(bipolar capacitor); Resulting capacitors
will be of same voltage, but half capacity of
single unit.
AC RIPPLE VOLTAGE-Sum of superimposed
peak AC voltage and DC voltage must not exceed
rated voltage. See figures 3, 6 and 9.
LEAKAGE CURRENT· - Current measured
throug h a 1,000n resistor with rated voltage
applied for 3 minutes at +25°C. This current
does not exceed 0.05 times capacitance (p.F)
times rated voltage (volts), or 2 p.A, whichever
is greater. At +85°C, typical leakage current
is less than 10 times the value at +25°C. See
figure 4.
IMPEDANCE-Measured at 10KHz and 25°C.
See figure 8.
DISSIPATION FACTOR-(tangent of loss angle:,
tanll) defined by tanll =2".fRC, is measured at
a frequency of 120 Hz, at room temperature;
25°C.
Protective Circuit Resistance
The failure rate of TAG capacitors will be
A = 4,2 X 16 -u h -1 at 3 Ohm/voltage circuit
resistance 85°C and rated voltage
Any lower resistance will increase the failure
rate.
This can be compensated by voltage derating.
See figures 12, 13, and 14.
Operational Reliability
The reliability is measured by the reject rate,
FR = m
nXh
where m = number of rejects. n X h = components
X hours.
The reject rate increases with applied voltage
VB and ambient temperature and falls with
increased circuit resistance R •. As a result of
comprehensive life-tests the reject rate has
been determined as a function of VB, and Rs.
The reject rate for catastrophic failures for
the particular case can be determined from
Fig. 12 to 14 as follows:
1. Determine the reject rate of FR" as a function
of the applied voltage from Fig. 12 with
= +85°C and Rs = 3nN.
2. Multiply FR" with the corresponding factor
from Fig. 13 for the actual ambient temperature
to obtain the reject rate FR'.
3. Determine the final reject rate FR as a
function of the circuit resistance by multiplying
FR' with the corresponding correction factor
obtained from Fig. 13 (ambient temperature as
parameter).
EXAMPLE: Determination of F for
VB = SOOA, FR" = 2.8 • 10- 7 • h- I (from Fig. 12)
llU = 125'C FA = 2.8· 10-7.9. h- I (from Fig. 13)
RS = InN Fe" = 2.8.10-7.9.2.8. h-' (from Fig. 14)
FR .= 7.06 x 10- 6 h- 1
Variation of tanll with temperature is shown
in figure 10.
16 -3