Technical Note

6/10

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2011.03 - Rev.B

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BA3259HFP,BA30E00WHFP

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Block Diagrams / Standard Example Application Circuits

Fig.25 BA3259HFP Block Diagram

Fig.26 BA30E00WHFP Block Diagram

Pin

No.

Pin

name

Function

1

Vcc

Power supply pin

2

ADJ

Variable output voltage detection pin

3

GND

GND pin

4

Vo2

Variable output pin

5

Vo1

3.3 V output pin

FIN

GND

GND pin

Pin

No.

Pin

name

Function

1

EN

Output on/off control pin: High active

2

Vcc2

Power supply pin 2

3

Vcc1

Power supply pin 1

4

GND

GND pin

5

Vo1

Power supply pin for 3.3 V output

6

Vo2

Variable output voltage detection pin

(0.8 V to 3.3 V)

7

ADJ

Variable output voltage detection pin

FIN

GND

GND pin

PIN

External capacitor

setting range

Vcc (1Pin)

Approximately 3.3µF

Vo1 (5Pin)

1 µF to 1000 µF

Vo2 (4Pin)

1 µF to 1000 µF

TOP VIEW

PIN

External capacitor

setting range

Vcc1 (3Pin)

Approximately 1 µF

Vcc2 (2Pin)

Approximately 1 µF

Vo1 (5Pin)

47 µF to 1000 µF

Vo2 (6Pin)

47 µF to 1000 µF

TOP VIEW

HRP5

HRP7

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Setting the Output Voltage Vo2

The following output voltage setting method applies to the variable output pin.

 ( 1 +

R2

) - R2

R1

(0.8 V typ.)

(0.05µA typ.: BA3259HFP)

(0.2µA typ.: BA30E00WHFP)

Note:Connect R1 and R2 to make output voltage settings as shown in Fig.25 and Fig.26. Keep in mind that the offset

R1

BA3259HFP: 1 kΩ to 10 kΩ

BA30E00HFP: 1 kΩ to 5 kΩ

The above is recommended.

1 2 3 4 5 6 7

Vo2

ADJ

R2

R1

1

2

3

4

5

Current

Limit

Thermal

Shutdown

Current

Limit

GND

3.3V

1μF

1.5V

1μF

3.3μF

1

5

4

FIN

2

ADJ

Vcc

R1

R2

3

GND

EN

Current

Limit

Sat.

Prevention

Current

Limit

Sat.

Prevention

Thermal

Shut Down

GND(Fin)

Vcc1

Vcc1

Vcc2

Vcc2

Vcc1

ADJ

GND

Vo2

Vo1

Vcc2

Reference

Voltage

R1

R2

47μF

47μF

1μF

1μF

1

2

3

4

5

6

7