Datasheet

UC28023
UC28025
SLUS557F -- MARCH 2003 -- REVISED AUGUST 2010
10
www.ti.com
APPLICATION INFORMATION
Figure 3. Open Loop Frequency Response
100
0
-- 4 0
1k 10 k 100 k 1 M 10 M 100 M
-- 2 0
60
20
40
80
100
--180
-- 9 0
0
G
A
IN
A
ND PH
A
SE
vs
FREQUENCY
f
OSC
-- Frequency -- Hz
A
V
-- G a i n -- d B
Phase -- °
GAIN
PHASE
3
2
5
4
1
0 0.2 0.4 0.6 0.8 1.0
t
delay
-- Delay Time-- μs
V
SEAout
-- E/A Output Voltage -- V
Figure 4. Unity Gain Slew Rate
VOLTAGE
vs
TIME
V
OUT
V
IN
CONTROL METHODS
6
7
CT
UC2802x
OSCILLATOR
1.25 V
RAMP
From
Error Amplifier
Figure 5. Voltage Mode Control
UDG--03050
C
T
Figure 6. Peak Current Mode Control
R
SENSE
UDG--03050
C
T
* A small filter may be required to supress switch noise.
6
7
CT
UC2802x
OSCILLATOR
1.25 V
RAMP
From
Error Amplifier
*
*
I
SENSE