Cautions and warnings

When using tantalum capacitors with a manganese dioxide coating, the following cautions and

warnings should be taken into account:

Polarity

Because tantalum capacitors are polar capacitors, it is important to observe their polarity

markings (positive pole on the anode, negative pole on the cathode). Any incorrect polarity

resulting from the sum of the AC and DC voltage components must be smaller than or equal to

the permitted polarity reversal voltage (see “General technical information”, section 4.6 and

section 4.8 under www.epcos.com/tantalum_capacitors). To avoid reducing their reliability, this

voltage may only occur for a short time, at most five times for a duration of one minute per hour.

Voltage

The maximum continuous voltage depends on the ambient temperature. Within the temperature

range of

55 to +85

°C, the rated voltage is equal to the maximum continuous voltage. Between

+ 85 and + 125

°C the maximum continuous voltage must be reduced linearly from the full rated

voltage to 2/3 of it (derating). At 150

°C (only B4519*P series) the voltage must be reduced to 1/2

and at 175

°C (only B4519*T series) to 1/3 of the rated voltage. Operation below the maximum

continuous voltage has a positive effect on the capacitor’s failure rate. The maximum continuous

voltage must not be exceeded (see“Quality and environment”, section 1.11 under

www.epcos.com/tantalum_capacitors).

All unfavourable operating conditions (such as possible line overvoltages, unfavourable

tolerances of the transformation ratio of the line transformer in the equipment, repeated

overvoltages when the equipment is switched on, high ambient temperatures) must be taken into

account when determining the operating voltage.

The surge voltage is the maximum voltage (peak value) that may be applied to the capacitor for

short periods, at most five times for a total duration of up to 1 minute per hour. The surge voltage

must not be applied for periodic charging and discharging in the course of normal operation and

cannot be part of the operating voltage. The permissible surge voltage for all capacitors in this

data book is 1.3 x the rated voltage. The occurrence of voltage impulses (transient voltages) that

exceed the surge voltage may lead to irreparable damage.

Capacitance

The actual capacitance of a capacitor can deviate from the rated capacitance by as much as the

full magnitude of the tolerance at delivery. The capacitance varies with the temperature (at

+125

°C +12% up to +20%) and decreases with increasing frequency (see “General technical

information”, section 5 under www.epcos.com/tantalum_capacitors).

Tantalum chip capacitors

B45196L, B45198L

Automotive

Page 14 of 16

Please read Important notes and

Cautions and warnings at the end of this document.