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| R⋅5RL |
• CURRENT BOOST CIRCUIT |
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| Output current of 60mA or more can be obtained by | ||||||
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| the current boost circuit constructed as shown in this cir- |
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| cuit diagram. |
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VIN |
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| VIN | R×5RL | VOUT | ||||||
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| SERIES |
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| VOUT | |||
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C1 |
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| GND |
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GND |
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• CURRENT BOOST CIRCUIT WITH OVERCURRENT LIMIT CIRCUIT
R2 | Tr.1 |
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Vbe2 |
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Tr.2 |
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| IOUT |
VIN | VIN | R×5RL VOUT |
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R1 |
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C1 |
| GND |
| C2 |
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GND 
GND
A circuit for protecting Tr.1 from the destruction caused by output
When the voltage reduction caused by the current (
IOUT) which flows through R2 reaches Vbe2 of Tr.2 by additionally providing the current boost circuit with Tr.2 and R2, Tr.2 is turned ON and the base current of Tr.1 is increased, so that the output current is limited.
Current limit of Overcurrent Limit Circuit is obtained as follows :
IOUT 
Vbe2/R2
• CURRENT SOURCE |
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| A current source with the structure as shown in this | ||
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| IOUT | circuit diagram can be used. Output Current IOUT is | ||
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| R×5RL | |||||
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VIN | SERIES |
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| obtained as follows : | |||||
R | |||||||||
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| *1 | /R + ISS | |||
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+ | GND |
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| IOUT= Vreg | |||||
ISS |
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C1 |
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| Take care that Output Current IOUT does not exceed | ||||
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its allowable current.
*1) Vreg : Set Output Voltage of R⋅5RL Series.
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