International Rectifier IRAUDAMP4, Руководство пользователя

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RD-0617
Figure 6. THD+N Ratio vs. Output Power for Different Switching Frequency Lock/Synchronization
Conditions
IRS20955 Gate Driver IC
The IRAUDAMP4 uses the IRS20955, which is a high-voltage (up to 200 V), high-speed
power MOSFET gate driver with internal deadtime and protection functions specifically
designed for Class D audio amplifier applications. These functions include OCP and
UVP. A bi-directional current protection feature that protects both the high-side and low-
side MOSFETs are internal to the IRS20955, and the trip levels for both MOSFETs can
be set independently. In this design, the deadtime can be selected for optimized
performance, by minimizing deadtime while limiting shoot-through. As a result, there is
no gate-timing adjustment on the board. Selectable deadtime through the DT pin voltage
is an easy and reliable function which requires only two external resistors, R11 and R9.
Figure 7. System-level View of Gate Driver IRS20955
100
0.001
0.01
0.1
1
10
%
100m 200 200m 500m 1 2 5 10 20 50 100
Power (W)
Self Osc. (ACD)
Int. Clock @ 300 kHz
Int. Clock @ 450 kHz
Self Osc. (Single Channel Driven)
R11
R9