TLE6280GP_07 Datasheet, PDF (5/25 Pages) Infineon Technologies AG – 3-Phase Bridge Driver IC

Datasheet TLE6280GP
The Input Low-side pins ILx (see Fig. 3) trigger the charge pump. As soon as the first exter-
nal low-side Mosfet is switched on and the corresponding bootstrap capacitor is connected
to GND, the C_CP is pushed to high and provides about 13V at the CH pin. C_CP can now di-
R_VS
VS
from battery
C_VS
= Pin
Bold line = external component
Vreg1 13V
+13 ... +8V
CH
C_CP
CL
Triggered
by ILx
Vreg3 =
Vreg1-8V
Vreg2=6V
BH
1
BH
2
BH
3
C_BH1
Phase A
Phase B
Phase C
BL
1
BL
2
BL
3
C_BL1
Fig. 2: Supply structure with external components (compare to Fig. 1)
rectly feed the low-side output stages and recharge the bootstrap capacitors connected to
GND.
As soon as the first of the 3 external low-side Mosfets is switched off, the C_CP will be pulled
down to be re-charged.
This synchronous operation with the output stages has the benefit that the electromagnetic
emissions generated by the charge pump can be filtered by the same filter necessary to filter
the EME of the converter itself. At the same time it is assured that the high voltage at the CH
pin is available just in time to charge the high-side bootstrap.
„ Timing of charge pump - Examples
Charge of bootstrap
1
capacitors
IL1
IL2
IL3
CH
1. ILx high
2
1. ILx low
Charge of charge pump
capacitor
Charge of bootstrap capacitors
IL1
IL2
IL3
CH
1. ILx high
1. ILx low
5
Charge of charge pump capa₂c₀ito₀r_7-07-19
Fig. 3: Trigger timing of charge pump caused by changing input signals