UC3844BD1 STMicroelectronics, UC3844BD1 Datasheet - Page 12

• Manufacturer Part Number: UC3844BD1
• Description: IC CTLR PWM HP CURR MODE SO-8
• Manufacturer: STMicroelectronics

Specifications of UC3844BD1

• Pwm Type: Current Mode
• Number Of Outputs: 1
• Frequency - Max: 500kHz
• Duty Cycle: 50%
• 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-SOIC
• Frequency-max: 500kHz
• Duty Cycle (max): 50 %
• Output Voltage: 4.90 V to 5.10 V
• Output Current: 1000 mA
• Mounting Style: SMD/SMT
• Switching Frequency: 500 KHz
• Operating Supply Voltage: 30 V
• Maximum Operating Temperature: + 150 C
• Fall Time: 50 ns
• Minimum Operating Temperature: - 40 C
• Rise Time: 50 ns
• Synchronous Pin: No
• Topology: Boost, Flyback
• For Use With: 497-8849 - BOARD DEMO STW9N150 100W 3PHASE
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: STUC3844BD1

Figure 24: Soft-Start Circuit
UC2842B/3B/4B/5B - UC3842B/3B/4B/5B
Figure 25: Soft-Start and Error Amplifier Output Duty Cycle Clamp.
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C
R2
R1
BC109
C
8
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2
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-
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R
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R
1
EA
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1
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BIAS
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where 0 <V
R
R
R
1mA
5
V
Clamp
BIAS
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2R
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5
I
pk(max)
ref
Comp/Latch
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D95IN355
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6
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