BD9305AFVM-TR_技术文档

Large Current External FET Controller Type Switching Regulators

Single-output Step-up,High-efficiency

Switching Regulator(Controller Type)

BD9306AFVM

Single-output Step-up,High-efficiency

Switching Regulator(Controller Type)

No.09028EAT04

BD9305AFVM

Description

BD9305AFVM / BD9306AFVM are 1-channel DC/DC converter controllers. Step-down DC/DC converter can be configured

by BD9305AFVM, and Step-up DC/DC converter can be configured by BD9306AFVM. In addition, the master slave function,

which is that the synchronization is possible at the time of multi-connection, is mounted.

Features

1) 1ch PWM Control DC/DC Converter Controller

2) Input Voltage Range:4.2 to 18V

3) Feed Back Voltage:1.25±1.6%

4) Oscillating Frequency Variable:100 to 800kHz

5) Built-in Soft Start Function

6) Standby Current of 0 A (Typ.)

7) Built-in Master / Slave Function

8) Protection Circuit : Under Voltage Lockout Protection Circuit

Thermal Shutdown Circuit

Short Protection Circuit of Timer Latch type

9) MSOP8 Package

Applications

・TV, Power Supply for the TFT-LCD Panels used for LCD TVs, Back Lights

・DSC, DVC, Printer, DVD ,DVD Recorder, Generally Consumer Equipments etc.

Absolute maximum ratings (Ta = 25°C)

Parameter

Symbol

Limit

Unit

Power supply voltage**

Vcc

Pd

20

588*

V

mW

℃

Power dissipation

Operating temperature range

Storage temperature range

Maximum junction temperature

Topr

Tstg

Tjmax

-40 to +85

-55 to +150

150

℃

* Reduced by 4.7 mW/°C over 25°C, when mounted on a glass epoxy 4-layer board (70 mm  70 mm  1.6 mm)

** Must not exceed Pd.

Recommended Operating Ranges (Ta=-40℃ to +85℃)

Limit

Parameter

Symbol

Unit

Min

4.2

－

Typ

12

－

Max

18

Power supply voltage

Control Voltage

Vcc

V_ENB

CT

V

Vcc

1000

50

Timing Capacity

100

5

－

pF

kΩ

kHz

Timing Resistance

Oscillating frequency

RT

－

Fosc

100

－

800

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Electrical Characteristics (Unless otherwise specified Ta=25℃,V_CC=12V,CT=200pF,RT=20kΩ)

Limit

Parameter

Symbol

Unit

Conditions

Min

Typ

Max

【Triangular Waveform Oscillator Block】

Oscillating frequency

FOSC

165

0.80

0.20

220

0.85

0.25

275

0.90

0.30

kHz

V

Vcc=5V

Charge Threshold Voltage

Discharge Threshold Voltage

VOSC^＋

VOSC^－

V

【Under-voltage lockout protection circuit】

Threshold Voltage

【Error amp Block】

Feed Back Voltage

Input Bias Current

VUT

3.5

－

4.2

V

VFB

IIB

1.230

－

1.250

0.05

50

1.270

1

V

µA

FB=1.5V

COMP Sink Current

COMP Source Current

【Gate Drive Block】

ON Resistance

IOI

35

65

FB=1.5V COMP=1.25V

FB=1.0V COMP=1.25V

IOO

35

50

65

Ron

VGDL

VGDH

MDT

－

5

0

－

0.5

－

Ω

V

Gate Drive Voltage L

Gate Drive Voltage H

MAX Duty (BD9305AFVM)

MAX Duty (BD9306AFVM)

【Control Block】

No Load

Vcc=5V

Vcc-0.5

－

Vcc

－

83

V

100

－

%

MDT

－

ON Voltage

VON

VOFF

IENB

2

－

60

－

0.3

90

V

OFF Voltage

－

40

ENB Sink Current

µA

ENB=5V

【Soft Start Block】

Soft Start Time

TS

－

10

－

ms

【Timer Latch Protection Circuit】

Latch Detection COMP Voltage

Latch Delay OSC Count Number

Latch Delay Time

VLC

CNT

DLY

1.5

－

1.7

2200

10

1.9

－

V

COUNT

ms

－

【Overall】

Standby Current

ISTB

ICC

－

0

10

µA

ENB=0FF

Average Consumption Current

1.0

1.5

2.5

mA

No Switching

*This product is not designed for protection against radio active rays.

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Electrical Characteristics (Unless otherwise specified,V_CC=12V, Ta=25℃)

300

280

260

240

220

200

1

0.5

0

4

3

2

1

0

℃

Ta=85

Ta=25

Ta=85

℃

Ta=25

℃

Ta=40

℃

-0.5

-1

℃

Ta=-40

10

0

5

15

20

25

0

1

2

3

4

5

-40

-15

10

35

60

85

INPUT VOLTAGE:VCC[V]

AMBIENT TEMPERATURE:Ta[

]

℃

Fig.1 Standby Circuit Current

Fig.3 Frequency vs Temperature

Fig.2 Average Consumption Current

0

-200

-400

-600

-800

-1000

1000

800

600

400

200

0

100

80

60

40

20

0

1

2

3

4

5

0

1

2

3

4

5

0

0.5

1

1.5

2

2.5

GD VOLTAGE:VGD[V]

COMP VOLTAGE:VCOMP[V]

Fig.5 GD Source Current

Fig.4 GD Sink Current

Fig.6 COMP Sink Current

1.252

1.250

1.248

1.246

1.244

0

-20

0.1

0.08

0.06

0.04

0.02

0

-40

-60

-80

-100

0

0.5

1

1.5

2

2.5

-40

-15

10

35

60

85

0.0

0.5

1.0

1.5

2.0

2.5

COMP VOLTAGE:VCOMP[V]

AMBIENT TEMPERATURE:Ta[

]

FB VOLTAGE:VFB[V]

℃

Fig.8 Feed Back vs Temperature

Fig.7 COMP Source Current

Fig.9 FB Input Bias Current

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Electrical Characteristics (Unless otherwise specified,Ta=25℃)

125

100

75

50

25

0

250

200

150

100

50

125

100

75

50

25

0

Ta=85

℃

Ta=25

℃

Ta=-40

℃

0

0.0

0.5

1.0

1.5

2.0

2.5

0.0

0.5

1.0

1.5

2.0

2.5

0.0

2.5

5.0

7.5

10.0

12.5

COMP VOLTAGE:VCOMP[V]

ENB VOLTAGE:VENB[V]

Fig.12 COMP vs DUTY

(BD9306AFVM)

Fig.10 ENB Input Current

Fig.11 COMP vs DUTY

(BD9305AFVM)

90

86

82

78

74

70

88

86

84

82

80

ΔV=166mV

Io=1A

VCC=12V Vo=5V

-40

-15

10

35

60

85

200

300 400

500

600 700

800

AMBIENT TEMPERATURE[

]

℃

SWITCHING FREQUENCY[kHz]

Fig.13 Temperature vs MAX Duty

(BD9306AFVM)

Fig.14 Frequency vs MAX Duty

(BD9306AFVM)

Fig.15 Load Response

(BD9305AFVM)

100

90

80

70

60

50

100

90

80

70

60

50

40

30

20

10

0

ΔV=380mV

VCC=12V Vo=5V

Io=SWEEP

Fsw=220kHz

Ta=25℃

VCC=12V Vo=16V

Io=SWEEP

Fsw=220kHz

Ta=25℃

40

30

20

10

0

Io=500mA

VCC=12V Vo=16V

0.0

0.5

1.0

1.5

2.0

0.0

0.2

0.4

0.6

0.8

1.0

OUTPUT CURRENT[A]

Fig.16 Load Response

(BD9306AFVM)

Fig.17 Efficiency Characteristics

(BD9305AFVM)

Fig.18 Efficiency Characteristics

(BD9306AFVM)

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Block Diagram

GND

Vcc

FB

COMP

7

6

8

5

Soft

Start

Err

1.25V

Vref

Timer

Latch

UVLO

TSD

Shut Down

PWM

Shut Down

DRV

OSC

VCC

ENABLE

2

3

1

4

ENB

GD

Vcc

CT

RT

FB

GND

COMP

7

6

8

5

Soft

Start

Err

1.25V

Vref

Timer

Latch

UVLO

TSD

Shut Down

PWM

DRV

OSC

ENABLE

3

2

1

4

ENB

GD

RT

CT

Fig19. Pin Assignment Diagram & Block Diagram (Above:BD9305AFVM / Below:BD9306AFVM)

Pin Assignment and Pin Function

Pin No

Pin Name

Function

Timing Resistance connection Pin

1

2

3

4

5

6

7

8

RT

CT

Timing Capacity connection Pin

Control Pin

ENB

GD

Gate Drive Output Pin

Power Supply Pin

Vcc

GND

COMP

FB

Ground pin

Error amp output Pin

Error amp inversion input Pin

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Block Diagram / Application Circuit

10000ｐF

5.1ｋΩ

VCC

GND

Vcc

FB

COMP

10uF

6

8

7

5

Soft

Start

Err

0.5Ω

1.25V

Vref

Timer

Latch

UVLO

(When Output Short,

Protect Fall VCC)

TSD

Shut Down

47uH

Vo

DRV

PWM

OSC

1ｋΩ

VCC

20uF

30ｋΩ

10ｋΩ

470pF

ENABLE

1

RT

2

3

4

ENB

GD

CT

20kΩ

200pF

10kΩ

VCC

Fig.20 Block Diagram / Application Circuit (BD9305AFVM)

10000pF

3.9kΩ

GND

Vcc

FB

COMP

10uF

5

6

8

7

Soft

Start

Err

47uH

1.25V

Vref

Timer

Latch

UVLO

TSD

Shut Down

Vo

PWM

DRV

OSC

200kΩ

1kΩ

20uF

100pF

15kΩ

ENABLE

3

2

1

4

ENB

GD

RT

CT

20Ω

200pF

10kΩ

VCC

Fig.21 Block Diagram / Application Circuit (BD9306AFVM)

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

Block Operation

・Error amplifier (Err)

It is a circuit that compares the standard voltage of 1.25V (TYP) and the feedback voltage of output voltage.

The switching Duty is determined by the COMP terminal voltage of this comparison result.

・Oscillator (OSC)

It is a block, in which the switching frequency is determined by RT and CT, and the triangular wave is determined by RT

and CT.

・PWM

The Duty is determined by comparing the output of Error amplifier and the angular wave of Oscillator.

The switching Duty of BD9306AFVM is limited by the maximum duty ratio that is determined by the internal part, and will

not be up to 100%.

・DRV

The gate of the power FET that is connected to the outside is driven by the switching Duty determined by PWM.

・VREF

It is a block that outputs the internal standard voltage of 2.5V (TYP).

The internal circuit is entirely the bearer of this standard voltage that is turned ON / OFF by the ENB terminal.

・Protection circuits (UVLO / TSD)

UVLO (low-voltage Lock Out circuit) shuts down the circuits when the voltage is below 3.5V (MIN).

Moreover, TSD (temperature protection circuit) shuts down the IC when the temperature reaches 175℃(TYP).

・Soft Start Circuit

The Soft Start Circuit limits the current at the time of startup while ramping up the output voltage slowly.

The overshoot of output voltage and the plunging current can be prevented.

・Timer Latch

It is an output short protection circuit that detects the output short if the output of error amplifier (COMP voltage) is more

than 1.7V (TYP). If the COMP voltage becomes more than 1.7V, the counter begins to operate, the LATCH is locked when

the counter counts to 2200, and the GD output shuts down. (＊the frequency of counter is determined by RT and CT.)

Once the LATCH is locked, the GD output does not operate until it is restarted by ENB or VCC. If the output short is

removed while the Timer latch is counting, the counter is reset.

Selecting Application Components

(1) Setting the output L constant (Step Down DC/DC)

The inductance L to use for output is decided by the rated current ILR and input current maximum value IOMAX of the

inductance.

IOMAX + IL should not

IL

2

VCC

reach the rated value level

ILR

IL

IOMAX mean

current

Vo

L

Co

t

Fig.22 Coil Current Waveform (Step Down DC/DC)

Fig.23 Output Application Circuit (Step Down DC/DC)

Adjust so that I_OMAX+ ΔI_L/ 2 does not reach the rated current value I_LR.

At this time, ∆I_Lcan be obtained by the following equation.

1

L

Vo

Vcc

1

f

ΔI_L=

X (Vcc-Vo)X

X

[A]

Set with sufficient margin because the inductance L value may have the dispersion of ± 30%.

If the coil current exceeds the rating current I_LRof the coil, it may damage the IC internal element.

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Technical Note

BD9306AFVM, BD9305AFVM

(2) Setting the output L constant (Step Up DC/DC)

The inductance L to use for output is decided by the rated current ILR and input current maximum value IINMAX of the

inductance.

VCC

IINMAX+ΔIL should not

2

IL

reach the rated value level

L

IL

Vo

IINMAX mean

current

Co

t

Fig.24 Coil Current Waveform (Step Up DC/DC)

Fig.25 Output Application Circuit (Step Up DC/DC)

Adjust so that I_INMAX+ ΔI_L/ 2 does not reach the rated current value I_LR.

At this time, ∆I_Lcan be obtained by the following equation.

1

L

Vo-Vcc

Vo

1

ｆ

ΔI_L=

Vcc X

X

[A]

Where, f is the switching frequency

Set with sufficient margin because the inductance L value may have the dispersion of ± 30%.

If the coil current exceeds the rating current I_LRof the coil, it may damage the IC internal element.

(3) Setting the output capacitor

For the capacitor C to use for the output, select the capacitor which has the larger value in the ripple voltage VPP

allowance value and the drop voltage allowance value at the time of sudden load change.

Output ripple voltage is decided by the following equation.

ΔIL

2Co

Vo

Vcc

1

f

ΔVPP = ΔIL X RESR +

X

[V]

(Step Down DC/DC)

(Step Up DC/DC)

1

fCo

Vcc

Vo

ΔIL

2

ΔVPP

=

ILMAX X RESR +

X

X (ILMAX -

) [V]

Perform setting so that the voltage is within the allowable ripple voltage range.

For the drop voltage during sudden load change; VDR, please perform the rough calculation by the following equation.

ΔI

Co

VDR =

X 10μ sec [V]

However, 10 s is the rough calculation value of the DC/DC response speed. Please set the capacitance considering the

sufficient margin so that these two values are within the standard value range.

(4)Setting of feedback resistance constant

For both BD9305AFVM (step down) and BD9306AFVM (step up), please refer to the following formula for setting of

feedback resistance.

We recommend 10kΩ~330kΩ as the setting range. If a resistance below 10kΩ is set, a drop in voltage efficiency will be

caused; if a resistance more than 330kΩ is set, the offset voltage becomes large because of the internal error amplifier’s

input bias current of 0.05µA(Typ). Please set the maximum setting voltage of BD9306AFVM (step up) in such a way that

Duty : (Vo - Vcc) / Vo is less than 70%.

Reference Voltage 1.25V

Vo

R1

R1 + R2

R2

FB

x 1.25

[V]

Vo ＝

－

8

ERR

＋

R2

Fig.26 Feedback Resistance Setting

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2009.05 - Rev.A

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Technical Note

BD9306AFVM, BD9305AFVM

(5) Setting of oscillation frequency

The angular wave oscillation frequency can be set by respectively connecting resistor and condenser to RT (1 pin) and CT

(2 pins). The currents to charge and discharge the condenser of CT are determined by RT.

Please refer to the following drawing for setting the RT’s resistor and the CT’s condenser.

RT:5~50kΩ, CT:100~1000pF, and the frequency range of 100kHz~800kHz are recommended.

Please pay attention to that, the switching will stop if your setting is off this range.

10000

Ta=25℃

VCC=12V

1000

100

10

CT=100pF

CT=200pF

CT=470pF

CT=1000pF

1

10

100

RT [kΩ]

Fig.27 Frequency Setting

(6)Selection of input condenser

For DC/DC converter, the condenser at the input side is also necessary because peak current is flowing between input

and output. Therefore, we recommend the low ESR condenser with over 10μF and below 100mΩ as the input condenser.

If a selected condenser is off this range, excessively large ripple voltage will overlaps with the input voltage, which may

cause IC malfunction.However, this condition varies with negative overcurrent, input voltage, output voltage, inductor’s

value, and switching frequency, so please be sure to do the margin check with actual devices.

(7)Selection of output rectifier diode

We recommend the Schottky barrier diode as the diode for rectification at the output stage of DC/DC converter. Please be

careful to choose the maximum inductor current, the maximum output voltage and the power supply voltage.

＜step-down DC/DC＞

⊿IL

2

Maximum inductor current

Power supply voltage

I_OMAX

＋

＜

Diode’s rated current

Diode’s rated voltage

Diode’s rated current

Diode’s rated voltage

VCC

＜step-up DC/DC＞

⊿IL

2

Maximum inductor current

I_INMAX

＋

Maximum output voltage

V_OMAX

Furthermore, each parameter has a deviation of 30%~40%, so please design in such a way that you have left a

sufficient margin for deviation in your design.

(8)Setting of Power FET

If step-down DC/DC is configured by BD9305AFVM, Pch FET is necessary; if step-up DC/DC is configured by

BD9306AFVM, Nch FET is necessary.

Please pay attention to the following conditions when you choose.

＜step-down DC/DC＞

⊿IL

2

Maximum inductor current

I_OMAX

＋

＜

FET’s rated current

Power supply voltage

VCC

Power supply voltage

Gate capacity (※)

＜

FET’s rated voltage

VCC

C_GATE

＞

＜

FET’s gate ON voltage

2000pF

＜step-up DC/DC＞

⊿IL

2

Maximum inductor current

I_INMAX

＋

＜

FET’s rated current

Maximum output voltage

Power supply voltage

V_OMAX

VCC

＜

＞

FET’s rated voltage

FET’s gate ON voltage

Gate capacity (※)

C_GATE

＜

2000pF

Furthermore, each parameter has a deviation of 30%~40%, so please design in such a way that you have left a sufficient

margin for deviation in your design.

(※) If Gate capacity becomes large, the switch’s switching speed gets slow, which may cause generation of heat and breakdown,

so please check thoroughly with actual devices.

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Technical Note

BD9306AFVM, BD9305AFVM

(9) Phase compensation

Phase Setting Method

The following conditions are required in order to ensure the stability of the negative feedback circuit.

Phase lag should be 150° or lower during gain 1 (0 dB) (phase margin of 30° or higher).

Because DC/DC converter applications are sampled using the switching frequency, the overall GBW should be set to 1/10

the switching frequency or lower. The target application characteristics can be summarized as follows:

Phase lag should be 150° or lower during gain 1 (0 dB) (phase margin of 30° or higher).

The GBW at that time (i.e., the frequency of a 0-dB gain) is 1/10 of the switching frequency or below.

In other words, because the response is determined by the GBW limitation, it is necessary to use higher switching

frequencies to raise response.

One way to maintain stability through phase compensation involves canceling the secondary phase lag (-180°) caused by

LC resonance with a secondary phase advance (by inserting 2 phase advances).

The GBW (i.e., the frequency with the gain set to 1) is determined by the phase compensation capacitance connected to

the error amp. Increase the capacitance if a GBW reduction is required.

(a) Standard integrator (low-pass filter)

(b) Open loop characteristics of integrator

(a)

A

-20 dB/decade

Gain

[dB]

＋

COMP

GBW(b)

A

Feedback

R

0

－

F

FB

0

C

-90°

Phase

[ ° ]

-90

Phase margin

-180°

-180

Fig. 28

1

2πRCA

Fig. 29

1

2πRC

Point (a) fa =

[Hz]

Point (b) fb = GBW =

[Hz]

The error amp performs phase compensation of types (a) and (b), making it act as a low-pass filter.

For DC/DC converter applications, R refers to feedback resistors connected in parallel.

From the LC resonance of output, the number of phase advances to be inserted is two.

1

LC resonant frequency fp =

[Hz]

2π√LC

Vo

1

R4

C1

Phase advance

fz1 =

fz2 =

[Hz]

R1

R2

2πC1R1

COMP

－

＋

1

A

2πC2R3

R3

C2

Fig. 30

Set a phase advancing frequency close to the LC resonant frequency for the purpose of canceling the LC resonance.

(※ )If high-frequency noise is generated in the output, FB is affected through condenser C1.

Therefore, please insert the resistor R4=1kΩ or so, which is in series with condenser C1.

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Technical Note

BD9306AFVM, BD9305AFVM

Example of application

※We recommend the application circuit examples with confidence, but hope that you will thoroughly check the characteristics

over again when putting them to use.

When you change the external circuit constant and use, please make a decision to leave a sufficient margin after taking

into consideration the deviation etc. of external components and ROHM IC, in terms of not only the static characteristic but

also the transient characteristic.

Moreover, please understand that our company can not confirm fully with regard to the patent right.

＜Master Slave Function＞

The master slave function, which is that the synchronous switching is possible by using these IC of BD9305AFVM /

BD9306AFVM through their multi-connection, is mounted. The following drawing shows an example of connection circuit

in which BD9305AFVM is connected on the master side and BD9306AFVM is connected on the slave side.

VCC

CTL1

CTL2

BD9305AFVM

BD9306AFVM

(Master Side)

(Slave Side)

CTL0

Vo2

RT

CT

Vo1

Fig.31 Master Slave Application Circuit

In the above-mentioned circuit, BD9306AFVM, which is synchronized with the switching frequency determined by RT and

CT of BD9305AFVM that is the master, operates.In addition, the ON/OFF of output can be controlled by connecting the

switch to the COMP terminal. (Refer to the following table)

Control signal correspondence table

Output state

Control signal

Vo1

OFF

ON

Vo2

OFF

ON

CTL0

Low

CTL1

＊

CTL2

＊

High

Low

High

Low

OFF

ON

＊The same in either case of High / Low.

Similarly in the case of connecting three or more than three, synchronization is possible by connecting the CT terminal of

Master and the CT terminal of Slave

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Technical Note

BD9306AFVM, BD9305AFVM

I/O Equivalent Circuit Diagram Fig.32

1.RT

VCC

4.GD

VCC

VREF

A

VCC(BD9305AFVM)

GND(BD9306AFVM)

A:

2.CT

VCC

7.COMP

VCC

VREF

3.ENB

8.FB

VCC

VREF

Fig. 32

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Technical Note

BD9306AFVM, BD9305AFVM

Notes for use

1) Absolute maximum ratings

Use of the IC in excess of absolute maximum ratings such as the applied voltage or operating temperature range may

result in IC damage. Assumptions should not be made regarding the state of the IC (short mode or open mode) when such

damage is suffered. A physical safety measure such as a fuse should be implemented when use of the IC in a special

mode where the absolute maximum ratings may be exceeded is anticipated.

2) GND potential

Ensure a minimum GND pin potential in all operating conditions.

3) Setting of heat

Use a thermal design that allows for a sufficient margin in light of the power dissipation (Pd) in actual operating conditions.

4) Pin short and mistake fitting

Use caution when orienting and positioning the IC for mounting on printed circuit boards. Improper mounting may result in

damage to the IC. Shorts between output pins or between output pins and the power supply and GND pins caused by the

presence of a foreign object may result in damage to the IC.

5) Actions in strong magnetic field

Use caution when using the IC in the presence of a strong magnetic field as doing so may cause the IC to malfunction.

6) Testing on application boards

When testing the IC on an application board, connecting a capacitor to a pin with low impedance subjects the IC to stress.

Always discharge capacitors after each process or step. Ground the IC during assembly steps as an antistatic measure,

and use similar caution when transporting or storing the IC. Always turn the IC's power supply off before connecting it to or

removing it from a jig or fixture during the inspection process.

7) Ground wiring patterns

When using both small signal and large current GND patterns, it is recommended to isolate the two ground patterns,

placing a single ground point at the application's reference point so that the pattern wiring resistance and voltage

variations caused by large currents do not cause variations in the small signal ground voltage. Be careful not to change the

GND wiring patterns of any external components.

8)Regarding input pin of the IC

This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them isolated.

P/N junctions are formed at the intersection of these P layers with the N layers of other elements to create a variety of

parasitic elements.For example, when the resistors and transistors are connected to the pins shown as follows, a parasitic

diode or a transistor operates by inverting the pin voltage and GND voltage.

The formation of parasitic elements as a result of the relationships of the potentials of different pins is an inevitable result

of the IC's architecture. The operation of parasitic elements can cause interference with circuit operation as well as IC

malfunction and damage. For these reasons, it is necessary to use caution so that the IC is not used in a way that will

trigger the operation of parasitic elements such as by the application of voltages lower than the GND (P substrate) voltage

to input and output pins.

Example of a SimpleMonolithic IC Architecture

Resistor

Transistor (NPN)

(Pin B)

B

E

(Pin A)

C

E

C

(Pin B)

B

GND

N

P

P+

Parasitic

elements

P+

N

P

N

(Pin A)

P substrate

GND

Parasitic elements

GND

Parasitic

elements

Parasitic elements

GND

Fig. 33

9) Overcurrent protection circuits

An overcurrent protection circuit designed according to the output current is incorporated for the prevention of IC damage

that may result in the event of load shorting. This protection circuit is effective in preventing damage due to sudden and

unexpected accidents. However, the IC should not be used in applications characterized by the continuous operation or

transitioning of the protection circuits. At the time of thermal designing, keep in mind that the current capacity has negative

characteristics to temperatures.

www.rohm.com

2009.05 - Rev.A

13/14

Technical Note

BD9306AFVM, BD9305AFVM

Ordering part number

B D

9

3

0

6

A

F

V M

-

T

R

Part No.

9306A

9305A

Package

Packaging and forming specification

TR: Embossed tape and reel

FVM: MSOP8

MSOP8

2.9 0.1

(MAX 3.25 include BURR)

Tape

Embossed carrier tape

3000pcs

+

6°

4°

Quantity

−4°

8

7

6

5

TR

Direction

of feed

The direction is the 1pin of product is at the upper right when you hold

reel on the left hand and you pull out the tape on the right hand

(

)

1

2

3

4

1PIN MARK

+0.05

1pin

+0.05

0.145

–0.03

0.475

S

0.22

–0.04

0.08

S

Direction of feed

Order quantity needs to be multiple of the minimum quantity.

0.65

Reel

(Unit : mm)

∗

www.rohm.com

2009.05 - Rev.A

14/14

Notice

N o t e s

No copying or reproduction of this document, in part or in whole, is permitted without the

consent of ROHM Co.,Ltd.

The content speciﬁed herein is subject to change for improvement without notice.

The content speciﬁed herein is for the purpose of introducing ROHM's products (hereinafter

"Products"). If you wish to use any such Product, please be sure to refer to the speciﬁcations,

which can be obtained from ROHM upon request.

Examples of application circuits, circuit constants and any other information contained herein

illustrate the standard usage and operations of the Products. The peripheral conditions must

be taken into account when designing circuits for mass production.

Great care was taken in ensuring the accuracy of the information speciﬁed in this document.

However, should you incur any damage arising from any inaccuracy or misprint of such

information, ROHM shall bear no responsibility for such damage.

The technical information speciﬁed herein is intended only to show the typical functions of and

examples of application circuits for the Products. ROHM does not grant you, explicitly or

implicitly, any license to use or exercise intellectual property or other rights held by ROHM and

other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the

use of such technical information.

The Products speciﬁed in this document are intended to be used with general-use electronic

equipment or devices (such as audio visual equipment, ofﬁce-automation equipment, commu-

nication devices, electronic appliances and amusement devices).

The Products speciﬁed in this document are not designed to be radiation tolerant.

While ROHM always makes efforts to enhance the quality and reliability of its Products, a

Product may fail or malfunction for a variety of reasons.

Please be sure to implement in your equipment using the Products safety measures to guard

against the possibility of physical injury, ﬁre or any other damage caused in the event of the

failure of any Product, such as derating, redundancy, ﬁre control and fail-safe designs. ROHM

shall bear no responsibility whatsoever for your use of any Product outside of the prescribed

scope or not in accordance with the instruction manual.

The Products are not designed or manufactured to be used with any equipment, device or

system which requires an extremely high level of reliability the failure or malfunction of which

may result in a direct threat to human life or create a risk of human injury (such as a medical

instrument, transportation equipment, aerospace machinery, nuclear-reactor controller,

fuel-controller or other safety device). ROHM shall bear no responsibility in any way for use of

any of the Products for the above special purposes. If a Product is intended to be used for any

such special purpose, please contact a ROHM sales representative before purchasing.

If you intend to export or ship overseas any Product or technology speciﬁed herein that may

be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to

obtain a license or permit under the Law.

Thank you for your accessing to ROHM product informations.

More detail product informations and catalogs are available, please contact us.

ROHM Customer Support System

http://www.rohm.com/contact/

www.rohm.com

R0039

A


型号：	BD9305AFVM-TR
厂家：	ROHM
描述：	暂无描述稳压器开关控制器
文件：	总15页 (文件大小：406K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

BD9305AFVM-TR [ROHM]

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