Datasheet
Design guidelines PM8834
12/20 DocID15086 Rev 3
5 Design guidelines
5.1 Output series resistance
An output resistance is generally introduced to allow high-frequency operation without
exceeding the maximum power dissipation of the driver package.
The value of the output resistance can be obtained as described in Section 5.2. For
applications with supply voltages (VCC) greater than 15 V, with low capacitive loads
(C
G
<10 nF), exercise caution when designing with PM8834.
In these circumstances, due to its high peak current capability, severe undervoltage on the
output pins may occur, which, if not limited in some way, can violate the safe operating area
of the output stage of the device. To avoid this phenomenon it is mandatory to add a gate
resistor R
G
of at least 1 Ω.
Figure 5. is a synthetic view of the boundaries for safe operation of PM8834.
Figure 5. Output series resistance
5.2 Power dissipation
The PM8834 embeds two high-current low-side drivers that can be used to drive high
capacitive MOSFETs. This section estimates the power dissipated inside the device in
normal applications.
Two main terms contribute to the device’s power dissipation: bias power and the power of
the driver.
• Bias power (P
DC
) depends on the static consumption of the device through the supply
pins and it is simply obtained as follows:
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