UC3842N Fairchild Semiconductor, UC3842N Datasheet - Page 6
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UC3842N
Manufacturer Part Number
UC3842N
Description
IC CTLR PWM CURR MODE 8-DIP
Manufacturer
Fairchild Semiconductor
Datasheet
1.UC3842D.pdf
(12 pages)
Specifications of UC3842N
Pwm Type
Current Mode
Number Of Outputs
1
Frequency - Max
500kHz
Duty Cycle
100%
Voltage - Supply
11.5 V ~ 30 V
Buck
No
Boost
No
Flyback
No
Inverting
No
Doubler
No
Divider
No
Cuk
No
Isolated
No
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
Operating Supply Voltage
30 V
Supply Current
17 mA
Maximum Operating Temperature
+ 70 C
Fall Time
35 ns
Minimum Operating Temperature
0 C
Rise Time
45 ns
Synchronous Pin
No
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
UC3842NFS
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
UC3842N
Manufacturer:
ST
Quantity:
20 000
Part Number:
UC3842NG4
Manufacturer:
TI/德州仪器
Quantity:
20 000
UC3842/UC3843/UC3844/UC3845
Oscillator timing capacitor, C
discharge time, the internal clock signal blanks the output to the low state. Selection of R
oscillator frequency and maximum duty cycle. Charge and discharge times are determined by the formulas:
t
Frequency, then, is: f=(t
6
c
t
= 0.55 R
D
ForRT
=
R
T
C
Figure 6. Oscillator Dead Time & Frequency
T
T
5K
I
n
C
T
0.0063R
--------------------------------------- -
0.0063R
,
f
=
(Deadtime vs C
-------------- -
R
1.8
T
C
T
c
T
T
–
+ t
–
2.7
4
d
)
T
-1
, is charged by V
Figure 5. Oscillator Waveforms and Maximum Duty Cycle
T
RT > 5k
Figure 8. Shutdown Techniques
REF
through R
T
and discharged by an internal current source. During the
Figure 7. Timing Resistance vs Frequency
T
and C
T
therefore determines both