TYPICAL APPLICATIONS
PROTECTION AND DIAGNOSIS FEATURES
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Supply Voltage (V)
Figure 24. Power Dissipation Profile of Application Using Charge Pump
Reference application with:
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Pump capacitor: 1.0 μF MLC
Pump filter capacitor: 47 μF low ESR aluminum electrolytic
Pump diodes: MUR120
Output FET gate charge: 240 nC @ 10 V
PWM Frequency: 20 kHz
Switching Single Phase
Below approximately 17 V the charge pump is actively regulating VPWR. The increased power dissipation is due to the charge
pump losses. Above this voltage the charge pump oscillator shuts down and VSYS is passed through the pump diodes directly to
VPWR
.
33937
Analog Integrated Circuit Device Data
Freescale Semiconductor
43
FREESCALE [ Freescale ]
