Datasheet


   
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SGLS245D − MAY 2004 − REVISED APRIL 2008
8
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
PARAMETER MEASUREMENT INFORMATION
Figure 1
Oscillator
The UCC2813-0/-1/-2/-3/-4/-5 oscillator generates a sawtooth
waveform on RC. The rise time is set by the time constant of RT and
CT. The fall time is set by CT and an internal transistor
on-resistance of approximately 125. During the fall time, the output
is off and the maximum duty cycle is reduced below 50% or 100%
depending on the part number. Larger timing capacitors increase
the discharge time and reduce the maximum duty cycle and
frequency.
0.2 V
2.5 V
S
RQ
REF
RC
C
T
R
T
8
4
Figure 2
Error Amplifier
Gain/Phase Response
Figure 3
UCC2813-3/5 V
REF
vs
V
CC
I
LOAD
= 0.5 mA
Figure 4
UCC2813-0/1/2/4 Oscillator Frequency
vs
R
T
and C
T