11
DEMO MANUAL DC252
DESIGN-READY SWITCHER
PCB LAYOUT A D FIL
U
W
Component Side Silkscreen
Component Side Copper (Layer 1)
Internal Copper (Layer 2)
Internal Copper (Layer 3)
OPERATIO
U
I
TH
pin waveforms that will give a sense of the overall loop
stability without breaking the feedback loop. The AC gain
of the loop will be increased by increasing R
C1
and the
bandwidth of the loop will be increased by decreasing C
C2
.
If R
C1
is increased by the same factor that C
C2
is de-
creased, the zero frequency will be kept the same, thereby
keeping the phase the same in the most critical frequency
range of the feedback loop. The output voltage settling
behavior is related to the stability of the closed-loop
system and will demonstrate the actual overall supply
performance. Capacitor C
C2
provides some high frequency
decoupling against transients. Be carefull not to overspecify
its value, as the response time to a load step will be
degraded. Again, monitoring the I
TH
pin will show any slew
rate limitations due to C
C1
. For further explanation of
optimizing loop response, refer to Application Note 76.
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
