●RIPPLE
The maximum permissible ripple voltage and current are related to the ratings case size. Please consult us detail in formations.
▶Ripple Current
The maximum permissible ripple current, IMAX, is calculated as follows :
PMAX
IMAX =
ESR(f)
where:
IMAX : Maximum permissible capacitor ripple current (Arms).
PMAX : Maximum permissible capacitor power loss (W).
Varies with the ambient temperature and case size.
Calculated according to Table
ESR(f): Capacitor equivalent series resistance (Ω).
Since the ESR(f) value varies with the ripple frequency, however, the following correction must be made in accordance with the operating frequency (see Fig. 4).
ESR(f) = K · ESR(120)
K : Coefficient for the operating frequency (Fig. 4).
ESR(120) = Tan δ · Xc = Tan δ 2πfC
where:
ESR(120) : Equivalent series resistance at 120 Hz (Ω).
Xc : Capacitive reactance at 120 Hz (Ω).
C: Electrostatic capacitance at 120 Hz (μF). f : Operating frequency (Hz).
Table.1 Maximum permissible power loss values (PMAX) by case size
Ambient |
|
|
| PM A X(W) |
|
| |
temperature | ℃ |
|
|
|
|
|
|
( ) | J | P | S | T | U | V | |
|
| ||||||
25 |
| 0.015 | 0.015 | 0.030 | 0.030 | 0.030 | 0.050 |
55 |
| 0.010 | 0.010 | 0.019 | 0.019 | 0.019 | 0.032 |
85 |
| 0.005 | 0.005 | 0.010 | 0.010 | 0.010 | 0.018 |
SCL Series