© by SEMIKRON / 2020-05-25 / Technical Explanation / SKYPER
®
12 PV
PROMGT.1026/ Rev.7/ Template Technical Explanation
Page 20/37
Description
Shape
Manufacturer
Art. no.
MELF resistors
MELF / MiniMELF SMD
Vishay Beyschlag,
Vishay Draloric,
Vitrohm
PRO MELF resistors,
SMM0207, SMM 0204,
ZCM series
4.11
External boost capacitors | Secondary side
The SKYPER
®
12 PV allows driving of semiconductor power modules with a gate charge (Q
G
) of up to 20µC
per output. To stabilize the gate voltages V
G(on)
and V
G(off)
during the semiconductor switching, the use of
boost capacitors for each output channel is recommended, if the connected gate charge is larger than
2.5µC. For maximum effectiveness, these capacitors have to be placed as close as possible to the
corresponding terminal as shown in Figure 15.
Figure 15: SKYPER
®
12 PV | Secondary side | Boost capacitors
The required capacitance of the optional external boost capacitors can be estimated by the following
equation:
𝐶
𝐵𝑆𝑇(𝑃)
= 𝐶
𝐵𝑆𝑇(𝑁)
= 𝐴 × 𝑄
𝐺
− 4.7µ𝐹 𝑓𝑜𝑟 2.5µ𝐶 < 𝑄
𝐺
≤ 20µ𝐶
𝐴 = 5 … 7
µ𝐹
µ𝐶
𝐼𝐺𝐵𝑇 7 𝑚𝑜𝑑𝑢𝑙𝑒
𝐴 = 4
µ𝐹
µ𝐶
𝐼𝐺𝐵𝑇 𝑚𝑜𝑑𝑢𝑙𝑒
Please note, when assembling boost capacitors at the secondary sides, also boost capacitors have to be
assembled at the primary side, as shown in Figure 9.
𝐶
𝐵𝑆𝑇
= 𝐶
𝐵𝑆𝑇(𝑃)
= 𝐶
𝐵𝑆𝑇(𝑁)
SKYPER
®
12 PV
C
B
S
T
(N
)_
T
O
P
C
B
S
T
(P
)_
T
O
P
PWR_VS_P_TOP X100:03
PWR_GND_TOP X100:08
PWR_VS_N_TOP X100:10
