Datasheet

8
7
6
1
2
R*
* R 0 for constant V
in
8
7
6
1
2
V
OUT
R
SC
V
IN
R
SC
V
IN
V
OUT
a) EXTERNAL npn SWITCH b) EXTERNAL npn SATURATED SWITCH (see Note A)
MC33063A
MC34063A
www.ti.com SLLS636M –DECEMBER 2004– REVISED JANUARY 2011
A. If the output switch is driven into hard saturation (non-Darlington configuration) at low switch currents (≤300 mA) and
high driver currents (≥30 mA), it may take up to 2 μs to come out of saturation. This condition will shorten the off time
at frequencies ≥30 kHz and is magnified at high temperatures. This condition does not occur with a Darlington
configuration because the output switch cannot saturate. If a non-Darlington configuration is used, the output drive
configuration in Figure 7b is recommended.
Figure 7. External Current-Boost Connections for I
C
Peak Greater Than 1.5 A
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