UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
Figure 4:
Oscillator Discharge Current vs. Tem-
perature.
I
dischg
(mA)
D95IN335
Figure 5:
Maximum Output Duty Cycle vs. Tim-
ing Resistor.
D95IN336
D
max
(%)
90
I
dischg
=7.5mA
80
I
dischg
=8.8mA
V
i
=15V
V
OSC
=2V
8.5
8.0
70
60
7.5
50
V
i
=15V
C
T
=3.3nF
T
A
=25°C
7.0
-55
-25
0
25
50
75
100 T
A
(°C)
40
0.8
1
2
3
5
R
T
(KΩ)
Figure 6:
Error Amp Open-Loop Gain and
Phase vs. Frequency.
(dB)
80
D95IN337
Figure 7:
Current Sense Input Threshold vs. Er-
ror Amp Output Voltage.
φ
30
60
90
V
th
(V)
1.0
D95IN338
Gain
60
40
V
i
=15V
V
O
=2V to 4V
R
L
=100K
T
A
=25°C
V
i
=15V
T
A
=25°C
0.8
T
A
=125°C
Phase
20
0
-20
10
120
150
180
f(Hz)
0.6
0.4
T
A
=-40°C
0.2
0.0
100
1K
10K
100K
1M
0
2
4
6
V
O
(V)
Figure 8:
Reference Voltage Change vs.
Source Current.
60
D95IN339
Figure 9:
Reference Short Circuit Current vs.
Temperature.
I
SC
(mA)
100
V
i
=15V
R
L
≤0.1Ω
D95IN340
V
i
=15V
50
40
T
A
=-40°C
T
A
=125°C
90
80
30
20
10
0
0
T
A
=25°C
70
60
50
20
40
60
80
100 I
ref
(mA)
-55
-25
0
25
50
75
100 T
A
(°C)
6/15
STMICROELECTRONICS [ STMICROELECTRONICS ]
