UC3842AN STMicroelectronics, UC3842AN Datasheet - Page 11

• Manufacturer Part Number: UC3842AN
• Description: IC CURR-MODE PWM CTRLR 8-MINIDIP
• Manufacturer: STMicroelectronics

Specifications of UC3842AN

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 500kHz
• Duty Cycle: 100%
• Voltage - Supply: 11.5 V ~ 25 V
• Buck: No
• Boost: Yes
• Flyback: Yes
• Inverting: No
• Doubler: No
• Divider: No
• Cuk: No
• Isolated: Yes
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 8-DIP (0.300", 7.62mm)
• Frequency-max: 500kHz
• Duty Cycle (max): 100 %
• Output Current: 1000 mA
• Mounting Style: Through Hole
• Switching Frequency: 500 KHz
• Maximum Operating Temperature: + 150 C
• Fall Time: 50 ns
• Minimum Operating Temperature: - 40 C
• Rise Time: 50 ns
• Synchronous Pin: No
• Topology: Boost, Buck, Flyback, Forward
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-3078-5

Figure 22: External Duty Cycle Clamp and Multi Unit Synchronization.
Figure 21: External Clock Synchronization.
f =
R
R
C
(R
A
B
SYNC INPUT
A
EXTERNAL
The diode clamp is required if the Sync amplitude is large enough to cause
the bottom side of C
V
1.44
+ 2R
REF
B
)C
6
5
2
5K
5K
5K
D
max
0.01 F
8
1
=
+
+
-
-
R
A
R
+ 2R
T
B
to go more than 300mV below ground
NE555
B
R
S
Q
47
R
C
4
T
T
V
REF
8
4
2
1
3
7
+
-
UC2842A/3A/4A/5A - UC3842A/3A/4A/5A
EA
+
8
4
2
1
R
R
+
-
BIAS
OSC
EA
TO ADDITIONAL
UCX84XAs
UCX84XAs
2R
+
R
R
R
5
BIAS
OSC
D95IN353
D95IN352
2R
R
5
11/15