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AN1625 APPLICATION NOTE

D1, D2

: 1N4148

R4

: 100

Ω (1/8 W)

C5

: 10 nF 100V ceramic

C8

: 220 nF 35V ceramic

Due to the high charge pump frequency, fast diodes are required. Connecting the cold side of the bulk capacitor

= 100

in all conditions. 1N4148 diodes withstand about 200 mA DC (1 A peak), and the maximum reverse voltage is 75

V, so they should fit for the majority of applications.

2.7 Sharing the Charge Pump Circuitry

If more than one device is used in the application, it's possible to use the charge pump from one L6235 to supply

The higher the number of devices sharing the same charge pump, the lower will be the differential voltage avail-

In this case it's recommended to omit the resistor on the CP pin, obtaining a higher current capability of the

charge pump circuitry.

Better performance can also be obtained using a 33 nF capacitor for C5 and using schottky diodes (for example

BAT47).

Sharing the same charge pump circuitry for more than 3÷4 devices is not recommended, since it will reduce the

Figure 8. Sharing the charge pump circuitry.

L6235

CP

C18 = 100 nF

To High -Side

Gate Drivers

L6235

C8 = 100 nF

To High -Side

Ga te Drivers

To other Devices

CP

D1 = BAT47

D2 = BAT47

C5 = 33nF