UC3843BD1G ON Semiconductor, UC3843BD1G Datasheet - Page 15

• Manufacturer Part Number: UC3843BD1G
• Description: IC CTRLR CURRENT MODE HP 8SOIC
• Manufacturer: ON Semiconductor

Specifications of UC3843BD1G

• 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-SOIC (3.9mm Width)
• Frequency-max: 275kHz
• Number Of Pwm Outputs: 1
• On/off Pin: No
• Adjustable Output: No
• Switching Freq: 500KHz
• Operating Supply Voltage (max): 30V
• Output Current: 1000A
• Synchronous Pin: No
• Rise Time: 50ns
• Fall Time: 50ns
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 8
• Package Type: SOIC N
• Duty Cycle (max): 96 % (Typ)
• Output Voltage: 4.9 V to 5.1 V
• Mounting Style: SMD/SMT
• Switching Frequency: 500 KHz
• Operating Supply Voltage: 30 V
• Maximum Operating Temperature: 70 C
• Minimum Operating Temperature: 0 C
• Topology: Boost or Flyback or Forward
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: UC3843BD1GOS

4.7k
18k
All outputs are at nominal load currents, unless otherwise noted
Line Regulation: 5.0 V
Load Regulation: 5.0 V
Output Ripple:
Efficiency
100
pF
0.01
4700pF
Test
150k
10k
8(14)
4(7)
2(3)
1(1)
115 Vac
±12 V
±12 V
5.0 V
±12 V
4.7
W
EA
Figure 34. 27 W Off−Line Flyback Regulator
V
V
V
V
V
R
R
in
in
in
in
in
I
I
out
out
+
= 95 to 130 Vac
= 115 Vac,
= 115 Vac,
= 115 Vac
= 115 Vac
Osc
= 1.0 A to 4.0 A
= 100 mA to 300 mA
Bias
MDA
Conditions
202
-
+
5(9)
5.0V Ref
+
Comp/Latch
D = 50 mV or ± 0.5%
D = 24 mV or ± 0.1%
D = 300 mV or ± 3.0%
D = 60 mV or ± 0.25%
250
S
R
http://onsemi.com
Q
40 mV
80 mV
Results
70%
+
-
15
56k
7(12)
pp
pp
7(11)
6(10)
5(8)
3(5)
100
1N5819
4.7k
+
1N4935
1N4937
68
22
470pF
1.0k
1N4935
3300
pF
47
MTP
4N50
+
0.5
T1
680pF
L2, L3
T1 -
2.7k
L1
MBR1635
Primary: 45 Turns #26 AWG
Secondary ±12 V: 9 Turns #30 AWG
(2 Strands) Bifiliar Wound
Secondary 5.0 V: 4 Turns (six strands)
#26 Hexfiliar Wound
Secondary Feedback: 10 Turns
#30 AWG (2 strands) Bifiliar Wound
Core: Ferroxcube EC35-3C8
Bobbin: Ferroxcube EC35PCB1
Gap: ≈ 0.10" for a primary inductance
of 1.0 mH
MUR110
MUR110
- 15 mH at 5.0 A, Coilcraft Z7156
- 25 mH at 5.0 A, Coilcraft Z7157
2200
1000
1000
+
+
+
1N4937
1000
L2
L1
L3
10
10
+
+
+
5.0V/4.0A
5.0V RTN
12V/0.3A
±
-12V/0.3A
12V RTN