0
200
400
600
I
O
(mA)
0
1
2
3
-2
-1
V
sat
(V)
D95IN341
V
i
=15V
80
µ
s Pulsed Load 120Hz Rate
T
A
=-40˚C
T
A
=25˚C
V
i
T
A
=-40˚C
T
A
=25˚C
GND
Sink Saturation
(Load to V
i
)
Source Saturation
(Load to Ground)
Figure 10: Output Saturation Voltagevs. Load
Current.
0
10
20
30
V
i
(V)
0
5
10
15
20
I
i
(mA)
UCX843/45
UCX842/44
R
T
=10K
C
T
=3.3nF
V
FB
=0V
I
Sense
=0V
T
A
=25˚C
D95IN342
Figure 11: Supply Current vs. Supply Voltage.
Figure 12: Output Waveform.
Figure 13: Output Cross Conduction
5V REG
OSCILLATOR
PWM
CLOCK
8
4
5
6
R
T
C
T
GND
OUTPUT
7
V
i
I
D
CT
OUTPUT
LARGE R
T
/SMALL C
T
CT
OUTPUT
SMALL R
T
/LARGE C
T
D95IN344
Figure 14: Oscillator and Output Waveforms.
V
i
=15V
C
L
= 1.0nF
T
A
= 25°C
90%
10%
50ns/DIV
V
i
=30V
C
L
= 15pF
T
A
= 25°C
V
O
I
CC
100ns/DIV
100mA/DIV
20V/DIV
UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
7/15