33883 datasheet(17/21 Pages) FREESCALE

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Analog Integrated Circuit Device Data



Freescale Semiconductor

33883

FUNCTIONAL DEVICE OPERATION

PROTECTION AND DIAGNOSTIC FEATURES

Figure 13. Limits of C1 Current and Voltage with Large Values of dV/dt

In the case of rapidly changing VCC voltages, the large dV/

dt may result in perturbations of the high-side driver, thereby

forcing the driver into an OFF state. The addition of

capacitors C3 and C4, as shown in Figure 14, reduces the

dV/dt of the source line, consequently reducing driver

perturbation. Typical values for R3/R4 and C3/C4 are 10



and 10 nF, respectively.

DV/DT AT VCC2

When the external high-side MOSFET is on, in case of

rapid negative change of VCC2 the voltage (VGATE_HS -

VSRC_HS) can be higher than the specified 18 V. In this case

a resistance in the SRC line is necessary to limit the current

to 5.0 mA max. It will protect the internal zener placed

between GATE_HS and SRC pins.

In case of high current (SRC_HS>100 mA) and high

voltage (>20 V) between GATE_HSX and SRC_HS an

external zener of 18 V is needed as shown in Figure 14.

tC1max

tC1min

VCC

I(C1+C2)

IC1max

IC1min

V(LR_OUT)

0 V

V(C1)

0 A

VC1min

33883 Datasheet(PDF) 17 Page - Freescale Semiconductor, Inc