UC3843BN ON Semiconductor, UC3843BN Datasheet - Page 13
UC3843BN
Manufacturer Part Number
UC3843BN
Description
IC CTRLR CURRENT MODE HP 8DIP
Manufacturer
ON Semiconductor
Datasheet
1.UC3842BDR2G.pdf
(21 pages)
Specifications of UC3843BN
Pwm Type
Current Mode
Number Of Outputs
1
Frequency - Max
275kHz
Duty Cycle
96%
Voltage - Supply
8.2 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
275kHz
Duty Cycle (max)
96 %
Output Voltage
4.9 V to 5.1 V
Output Current
1000 mA
Mounting Style
Through Hole
Switching Frequency
500 KHz
Operating Supply Voltage
30 V
Maximum Operating Temperature
+ 70 C
Fall Time
50 ns
Minimum Operating Temperature
0 C
Rise Time
50 ns
Synchronous Pin
No
Topology
Boost, Flyback, Forward
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Other names
UC3843BNOS
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
UC3843BN
Manufacturer:
ST
Quantity:
7 000
Part Number:
UC3843BN
Manufacturer:
ST
Quantity:
20 000
Part Number:
UC3843BN/ON
Manufacturer:
ON/安森美
Quantity:
20 000
Company:
Part Number:
UC3843BNG
Manufacturer:
ON
Quantity:
11 000
Company:
Part Number:
UC3843BNG
Manufacturer:
ON Semiconductor
Quantity:
3 300
Part Number:
UC3843BNG
Manufacturer:
ON/安森美
Quantity:
20 000
Part Number:
UC3843BNG ON
Manufacturer:
ON/安森美
Quantity:
20 000
+
-
5.0V Ref
Comp/Latch
R
S
Q
Figure 28. MOSFET Parasitic Oscillations
Figure 30. Isolated MOSFET Drive
Series gate resistor R
caused by the MOSFET input capacitance and any series wiring inductance in
the gate-source circuit.
+
-
5.0V Ref
7(12)
Comp/Latch
+
-
V
CC
7(11)
6(10)
5(8)
3(5)
g
R
S
will damp any high frequency parasitic oscillations
C
Q
Boundary
Isolation
R
R
S
7(12)
+
-
N
V
S
CC
Q1
7(11)
6(10)
5(8)
3(5)
R
g
V
N
+
in
0
-
P
I p k +
50% DC
http://onsemi.com
V (Pin1) * 1.4
Q1
R
V
V
in
S
GS
3 R S
Waveforms
+
0
-
13
N S
N p
25% DC
The MCR101 SCR must be selected for a holding of < 0.5 mA @ T
transistor circuit can be used in place of the SCR as shown. All resistors are 10 k.
+
0
-
The totem pole output can furnish negative base current for enhanced
transistor turn-off, with the addition of capacitor C
MCR
101
I
Figure 29. Bipolar Transistor Drive
B
Figure 31. Latched Shutdown
3905
2N
Base Charge
Removal
3903
8(14)
2N
4(7)
2(3)
1(1)
6(10)
5(8)
3(5)
C1
1
.
EA
R
R
+
Q1
A(min)
Osc
R
V
1.0 mA
in
S
Bias
. The simple two
2R
R
5(9)