BM1Q021FJ [ROHM]

准谐振控制器型DC/DC转换器IC BM1Q021FJ为所有存在插口的产品提供优良的系统。为准谐振动作，实现了软开关，有助于实现低EMI。外接开关MOSFET及电流检测电阻，可实现自由度高的电源设计。本IC内置启动电路，有助于实现低待机功耗和高速启动。轻负载时内置脉冲串功能且IC消耗电流低，因此待机功耗会变小。本IC内置软启动功能、脉冲串功能、逐周期过电流限制、过电压保护、过负荷保护、CS开路时保护等各种保护功能，安全性优异。;


型号：	BM1Q021FJ
厂家：	ROHM
描述：	准谐振控制器型DC/DC转换器IC BM1Q021FJ为所有存在插口的产品提供优良的系统。为准谐振动作，实现了软开关，有助于实现低EMI。外接开关MOSFET及电流检测电阻，可实现自由度高的电源设计。本IC内置启动电路，有助于实现低待机功耗和高速启动。轻负载时内置脉冲串功能且IC消耗电流低，因此待机功耗会变小。本IC内置软启动功能、脉冲串功能、逐周期过电流限制、过电压保护、过负荷保护、CS开路时保护等各种保护功能，安全性优异。开关控制器软启动脉冲转换器
文件：	总30页 (文件大小：1467K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

Datasheet

AC/DC Drivers

Quasi-Resonant Control type

DC/DC Converter IC

BM1Q021FJ /BM1Q041FJ

General Description

Features

The quasi-resonant controller typed AC/DC converter IC

BM1Q021FJ/BM1Q041FJ provides an optimum system for

all products that include an electrical outlet.

Quasi-resonant operation enables soft switching and helps

to keep EMI low.

 Quasi-resonant method

 Built-in 650V tolerate start circuit

 Low power when load is light ( Burst operation)

 Maximum frequency control (120kHz)

 Frequency reduction function

With MOSFET for switching and current detection resistors

as external devices, a higher degree of design freedom is

achieved.

As BM1Q021FJ/BM1Q041FJ built in HV starter circuit, it

contributes to low consumption power and high speed start.

Because the built-in burst mode is reduced switching loss

and IC consumption current is low, Stand-by power is very

low.

Because BM1Q021FJ/BM1Q041FJ built-in soft-start, burst

mode, over current limiter which is cycle-by-cycle, over

load protection, over voltage protection, CS open protection

and so on, BM1Q021FJ/BM1Q041FJ are highly safety.

 AC voltage correction function

 VCC pin : under voltage protection

 VCC pin : overvoltage protection

 Over-current protection (cycle-by-cycle)

 OUT pin : H voltage 12V clamp

 Soft start

 ZT trigger mask function

 ZT Over voltage protection[BM1Q021 Auto-restart]

 FB Over Load protection [Auto-restart]

 CS pin open protection [Auto-restart]

Package

SOP-J8

4.90mm × 6.00mm × 1.65mm

(Typ.) (Typ.) (Max.)

Key Specifications

 Operating Power Supply Voltage Range:

VCC：8.9V to 26.0V

VH： to 600V

 Operating Current:

 Max frequency:

Normal：0.60mA (Typ.)

Burst ： 0.35mA(Typ.)

120kHz(Typ.)

 Operate temperature range:

-40℃ to +105℃

Applications

Typical Application Circuit

AC adapters and household appliances (printer, TV,

vacuum cleaners, air cleaners, air conditioners, IH

cooking heaters etc.)

Line Up

ZT OVP

BM1Q021FJ

BM1Q041FJ

Auto-restart

None

Figure 1. Application Circuit

○Product structure：Silicon monolithic integrated circuit ○This product is not designed protection against radioactive rays

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Absolute Maximum Ratings（Ta=25C）

Item

Symbol

Vmax1

Vmax2

Vmax3

Vmax4

Vmax5

I_OH

I_OL

I_SZT1

I_SZT2

Rating

-0.3 ~ 30

-0.3 ~ 6.5

-0.3 ~ 7.0

-0.3 ~ 15

-0.3 ~ 650

-0.5

Unit

^oC

Condition

Input voltage range 1

Input voltage range 2

Input voltage range 3

Input voltage range 4

Input voltage range 5

OUT pin out peak current1

OUT pin out peak current2

ZT pin current1

VCC

CS, FB

OUT

1.0

-3.0

3.0

ZT pin current2

Allowable dissipation

Operating temperature

Max junction temperature

Storage temperature range

0.67(Note1)

-40 ～ +105

150

Topr

Tjmax

Tstr

-55 ～ +150

(Note1) When mounted (on 70 mm × 70 mm, 1.6 mm thick, glass epoxy on single-layer substrate).

Reduce to 5.4 mW/C when Ta = 25C or above.

Caution: Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit

between pins or an open circuit between pins and the internal circuitry. Therefore, it is important to consider circuit protection

measures, such as adding a fuse, in case the IC is operated over the absolute maximum ratings.

Operating Conditions（Ta=25C）

Parameter

Symbol

VCC

Rating

8.9～26.0

80～600

Unit

Conditions

Power supply voltage range 1

Power supply voltage range 2

VCC

Electrical Characteristics (Unless otherwise noted, Ta = 25C, VCC = 15 V)

Specifications

Parameter

［Circuit current］

Symbol

Unit

Conditions

MIN

TYP

MAX

FB=2.0V

Circuit current (ON)1

Circuit current (ON)2

I_ON1

600

1000

(Switching operation)

FB=0.5V

I_ON2

I_OFF

350

450

(Switching OFF)

VCC=12V , VH:open

VCC UVLO = disable

Circuit current(OFF)

［VH pin starter］

VH Start current1

VH Start current2

I_START1

I_START2

0.400

1.00

0.700

3.00

1.000

6.00

VCC= 0V

VCC=10V

Released VCCUVLO

VH pin current

VCC pin

VH OFF current

I_START3

V_SC

VH start current switched voltage

0.400

0.800

1.400

［VCC pin protection］

VCC UVLO voltage1

VCC UVLO voltage2

VCC UVLO hysteresis

VCC charge start voltage

VCC charge end voltage

VCC OVP voltage1

V_UVLO1

V_UVLO2

V_UVLO3

V_CHG1

V_CHG2

V_OVP1

V_OVP2

V_OVP3

12.50

7.50

7.70

12.00

26.00

13.50

8.20

5.30

14.50

8.90

9.70

14.00

29.00

VCC rise

VCC fall

V_UVLO3=V_UVLO1-V_UVLO2

Starter circuit

Stop voltage from V_CHG1

VCC rise

8.70

13.00

27.50

23.50

4.00

VCC OVP voltage2

VCC OVP hysteresis

VCC fall

［OUT pin］

OUT pin H voltage

OUT pin L voltage

OUT pin Pull-down resistor

V_OUTH

V_OUTL

R_PDOUT

10.5

12.5

100

14.5

0.30

125

kΩ

IO=-20mA, VCC=15V

IO=+20mA

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IC control unit Electrical Characteristics (Unless otherwise noted, Ta = 25C, VCC = 15 V)

Specifications

Parameter

Symbol

Unit

Conditions

MIN

TYP

MAX

[ DC/DC converter unit （Turn-off）]

Pull-up resistor of FB pin

CS over current voltage 1A

CS over current voltage 1B

CS over current voltage 2A

R_FB

22.5

0.475

0.310

0.100

0.062

30.0

0.500

0.350

0.125

0.088

37.5

0.525

0.390

0.150

0.113

kΩ

V_lim1A

V_lim1B

V_lim2A

V_lim2B

FB=2.2V (ACSNS＝L)

FB=2.2V (ACSNS＝H)

FB=0.5V (ACSNS＝L)

FB=0.5V (ACSNS＝H)

CS over current voltage 2B

Voltage gain1

（ΔVFB/ΔVCS）

Voltage gain 2

（ΔVFB/ΔVCS）

AV_CS1

AV_CS2

3.40

4.86

4.00

5.71

4.60

6.57

V/V

ACSNS＝L

ACSNS＝H

ZT current switched CS 1

ZT current switched CS 2

ZT current hysteresis

switched CS voltage

CS Leading Edge Blanking

I_ZT1

I_ZT2

0.93

0.82

1.00

0.90

1.07

0.98

I_ZTHYS

T_LEB

0.10

0.250

0.150

At applying PULSE to the

CS pin

Turn-off time

T_OFF

Minimum ON width

Maximum ON width

T_min

T_max

0.400

39.0

T_LEB＋T_OFF

30.0

50.7

[ DC/DC converter unit （Turn-on）]

ZT input current 1

ZT input current 2

ZT input current 3

Max frequency 1

I_ZT1

I_ZT2

I_ZT3

F_SW1

F_SW2

108

120

132

kHz

OUT=L, ZT=4.65V

OUT=L, ZT=5.00V

OUT=L, ZT=5.35V

FB=2.0V

Max frequency 2

FB=0.5V

Frequency reduction start

voltage

V_FBSW1

1.10

1.25

1.40

Frequency reduction end voltage

ZT comparator voltage1

ZT comparator voltage2

V_FBSW2

V_ZT1

V_ZT2

0.42

120

0.50

100

200

0.58

140

280

ZT fall

ZT rise

In OUT H ->L,

prevent noise

No bottom detection

From final ZT trigger

ZT trigger mask time

T_ZTMASK

0.6

ZT trigger Timeout1

ZT trigger Timeout2

T_ZTOUT1

T_ZTOUT2

10.5

3.5

15.0

5.0

19.5

6.5

[DC/DC protection ]

Soft start time1

Soft start time 2

Soft start time 3

Soft start time 4

FB Burst voltage

FB OLP voltage a

FB OLP voltage b

FB OLP delay timer

FBOLP stop timer

Protection mask time

ZT OVP voltage

T_SS1

T_SS2

T_SS3

T_SS4

V_BURST

0.35

0.70

1.40

2.80

0.42

2.6

0.50

1.00

2.00

4.00

0.50

2.8

2.6

512

100

5.00

512

0.65

1.30

2.60

5.20

0.58

3.0

V_FOLP1A

FBOLP detect（FB rise）

FBOLP detect（FB fall）

V_FOLP1B

T_FOLP

T_OLPST

T_mask

V_ZTL

V_ZTOVP

44.8

358

4.65

358

83.2

666

200

5.35

666

BM1Q021FJ

ZTOVP stop timer

* Definition of ACSNS (L : ZT current＜I_ZT1,H : ZT current > I_ZT1

)

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Pin Configuration

Table 1 Input-Output PIN Function

Function

ESD Diode

GND

NO.

Pin Name

I/O

VCC

GND

OUT

VCC

N.C.

Zero current detect pin

Feedback signal input pin

Primary current sensing pin

GND pin

External MOS drive pin

Power supply pin

○

I/O

Non Connection

Starter circuit pin

○

External Dimensions

4 . 9 ±0 . 2

MAX 5.25 ( include BURR)

1Q0X1

Lot No.

0 . 2 ±0 . 1

11..2277

0 . 4 2 ±0 . 1

(Unit:mm)

Figure-2 External Dimensions

I/O Equivalent Circuit Diagram

Figure-3 I/O Equivalent Circuit Diagram

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Block Diagram

VOUT

FUSE

85-

265Vac

Diode

Bridge

Filter

Cvcc

VCC

Starter

12V Clamp

Circuit

VCC UVLO

4.0V Regulator

13.5V/

8.2V

13.0V/

8.7V

NOUT

Internal

Supply

ZT ACSNS Com.p

VCC OVP

ZT OVP

27.5V

OSC

Rzt1

OSC

1shot

Comp.

^(*)TimeOut

・ 15 us

ERROR

AMP

AND

・

5 us

Czt

POUT

NOUT

Trigger

Rzt2

100mV

/200mV

detect LOGIC

AND

OUT

PRE

Driver

ZT Blanking

OUT(H->L)

0.60us

FBOLP _OH

AND

NOUT

Max frequency

control

VREF (4V)

30k

Burst

Comp.

BURST_OH

VREF (4V)

0.50V.

Cfb

OLP1

1MΩ

FBOLP_OH

delay Timer

(64ms)

Stop Timer

(512ms)

OVP

^ZTO

(BM1Q021FJ)

Soft Start

DCDC

Comp.

300kΩ

100kΩ

FB/4

0.50V

1ms

0.5ms

2ms

4ms

CURRENT SENSE(V-V Change)

Normal : ×1.0

Leading Edge

Blanking

GND

Figure-4 Block Diagram

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Description of Blocks

( 1-1 ) Starter Circuit VH pin（8pin）

IC builds in starter circuit (tolerates 650V) to VH pin (8pin). It enables to be low standby power and high speed starting.

The operating current is shown in Figure-6.After starting IC, consumption power is decided by multiplied idling current I_START3

（typ=10uA） with VH voltage. The loss by the idling current is below.

ex) power consumption of starter circuit only

Vac=100V Power＝100V*√2*10uA=1.41mW

Vac=240V Power＝240V*√2*10uA=3.38mW

Start time is decided by VH current and VCC pin capacitor.

The reference value of start time is shown in Figure7. For example, VCC capacitor is charged within 0.1s in C_VCC=10uF

When VCC pin is shorted to GND, current of “I_START1” flows. (Figure-6)

When VH pin is shorted to GND, large current flows from VH line to GND. To prevent it, need to insert

resistor (5kΩ~60kΩ) of “R_VH” to limit current between VH line and VH pin.

When VH pin is shorted to GND, the power of VH²/R_VHis applied. For that, please decide resistor size to confirm power

dissipation. When it does not satisfy power dissipation by one resistor, please use more than two resistors.

Figure-5 Starter Block Diagram

VCC Cap[uF]

Figure-6 Start-up Current vs VCC Voltage

Figure-7 Start-up Time（example）

*The start up current is flown from VH pin(8Pin).

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It shows operation waveform of start-up in Figure-8.

Figure-8 Start-up Waveform

A: By inserting to outlet, VH voltage applies. From the time, charging to VCC pin starts from VH pin through starter circuit.

At the time, due to VCC < V_SC(typ=0.8V), VH input current is limited to I_START1by VCC pin short protection.

B: Because of VCC voltage > V_SC(typ=0.8V), VCC short protection is released, the current flows from VH pin.

C: Because of VCC voltage > V_UVLO1(typ=13.5V), the start-up stops, and VH input current is limited to I_START3(typ=10uA)

Furthermore, because switching operation starts, Secondary output rises. However, because Secondary output is low,

VCC pin voltage is decreased. The falling rate of VCC is determined by VCC pin capacitance, the consumption current

of IC and the load current that flows from the VCC pin. ( V/t = Cvcc/Icc )

D: Because secondary output has risen to specific voltage, VCC pin voltage is applied from the auxiliary winding and VCC

voltage is stabilized.

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( 1-2 ) In Case of Useless VH pin (8pin)

This IC is also possible to start by connecting the start-up resistor to the VCC pin in the open the start-up circuit (650V

breakdown voltage) of the VH pin. The structure that do not use the recharge function is shown in Figure- 9.

At start-up (before VCC VULO releasing) , please be careful to set the start-up resistor shown in blue because the

consumption current I_OFF（Max=25uA） flows from VCC pin(6pin). Also, in case of not to use recharge function, the same

circuit is used.

Figure-9 Application Circuit not to use VH Pin (8pin)

・How to set the start-up resistance

Start-up resistor Rstart shown in Figure-9 in blue, is necessary for the IC to start if you do not use the VH pin.

If you reduce Rstart value, standby power is increased, start-up time is shorter.

If you increase Rstart on the contrary, standby power is reduced, start-up time will be longer.

When the voltage VCC=12V, standby current I_OFFis 25μA (max), VCC UVLO voltage V_UVLO1is 14.5V (max).

ex） The example of start-up resistor Rstart setting

Rstart = (Vmin- V_UVLO1（max）) / I_OFF（max）

In Vac=100V, if margin is -30% , VHmin=100×√2×0.7=99V

V_UVLO1（max）=14.5V ,so

Rstart ＝(99-14.5) / 25μA＝3.38MΩ

For an example, with a sufficient margin to 3.38MΩ, and the Rstart is 2.0MΩ..

For AC100V, Power consumption in Rstart is below.

Pd (Rstart) = (VH-VCC)²/Rstart = (141V-14.5V) ²/2.0M = 8.00mW

Pd in using start-up resistor is more than in using VH pin,

However for VCC pin capacitance value and VCC start-up resistor, please confirm by performing the evaluation of the actual

application.

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(2 ) Start Sequence (Soft start, Light load operation, Auto recovery in over load protection)

The start sequence of IC is shown in Figure-10. About each detail, explain in each section.

Figure-10 Start Sequence Time Chart

A: Input voltage from AC line is supplied to VH pin(8Pin).

B : VCC pin（6pin） voltage is rise, when VCC＞V_UVLO1（typ=13.5V）, IC starts operating.

In case of protection function is no active, IC starts to switching operation.

Then VCC pin voltage is dropped in cause of VCC (6pin) consumption current.

In case of VCC< V_CHG1（typ=8.7V）, starter circuit is operated, IC starts to charge VCC pin. After starting of charge, IC

continues to charge until VCC> V_CHG2（typ=13.0V）.

C: There is a soft start function which regulates the voltage level at the CS pin to prevent a rise in voltage and current.

D: When the switching operation starts, VOUT rises.

Once the output voltage starts-up, set to stable the output voltage to within the T_FOLP(min=44.8ms) period

E: When it is light load, burst operation is used to keep power consumption down.

F: When it is heavy load, FB pin voltage (2pin) is larger than V_FOLP1A(typ=2.8V), because output voltage is down.

G: When the FB pin(2pin) voltage keeps V_FOLP1A(typ=2.8V) at or above T _FOLP(64ms typ), switching is stopped by the over load

protection for T_OLPST(typ=512ms).

When the FB pin(2pin) voltage does not keep V_FOLP1B(typ=2.6V) at T _FOLP(64ms typ), the timer of T_FOLP(typ=64ms) is reset.

H : When VCC voltage（6pin） is V_CHG1（typ=8.7V） or less, starter circuit starts to charge VCC pin(6pin) to operate starter

circuit.

I : When VCC voltage (6pin) is over than V_CHG2（typ =13.0V）,starter circuit stops to charge VCC pin(6pin).

J: The same as F.

K: The same as G.

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(3) VCC pin(6pin) Protection Function

IC built in VCC UVLO（Under Voltage Lock Out） function and VCC OVP (Over Voltage Protection) function and VCC charge

function.

VCC UVLO function is the protection for VCC (pin) voltage is low. VCC OVP function is the protection for VCC (6pin) voltage is

high. They are for preventing MOSFET from destroying for switching in VCC voltage low or high.

VCC charge function is stable for output voltage in VCC pin voltage low, because starter circuit charge VCC pin from VH line.

(3-1) VCC UVLO / VCC OVP Function

VCCUVLO is an auto recovery type that has voltage hysteresis. VCCOVP is an auto recovery type that has voltage hysteresis.

When VCC pin voltage is larger than V_OVP1（typ=27.5V）, switching stops until VCC pin voltage is smaller than V_OVP2(typ=23.5V).

Figure-11 VCC UVLO / OVP Timing Chart

A: VH (8pin) voltage input, VCC (6pin) voltage starts rising.

B: VCC pin voltage >VUVLO1, releases the VCC UVLO function and DC/DC operation starts.

C: VCC pin voltage >VOVP1, VCCOVP detects the over-voltage.

D: VCC pin voltage <VOVP2, VCCOVP release and switching restart.

E: VH line voltage is down.

J: VCC < V_UVLO2,VCC UVLO function starts to operate.

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・For Capacitor Value of VCC pin

For stable operation of the IC, please set the 1uF or higher capacitor value of VCC pin. When the VCC capacitor

terminal is too large, response of the VCC pin to the Secondary output is slows down. Please be careful.

If the degree of the transformer coupling is low, since a large surge occurs to the VCC pin, the IC may be destroyed. In

this case, please attach a resistor which is from 10Ω to 100Ω to the path between the capacitor and diode at the back of

the auxiliary winding. Please set the resistance value in order that surge of VCC pin does not exceed the absolute

maximum rating of the VCC pin by performing the waveform evaluation of VCC pin.

・For settings VCC OVP voltage protection when Vout (Secondary output) is increased

VCC pin voltage is determined by the transformer ratio and Vout ( Secondary output ).Therefore, when the Secondary

output is large, it is possible to protect IC by VCCOVP. Setting VCCOVP protection is below.

Vout

Figure-12 How to Set VCCOVP

VCC voltage = Vout×Nb/Ns -VF (Vout:Secondary output, Nb:Number of auxiliary winding, Ns:Number of secondary

winding)

If you wish to apply protection when it becomes Secondary output × 1.3, please set the number of turns so that

1.3×(Vout×(Nb/Ns)-VF) > VOVP1

VCCOVP is detected when VCC voltage is higher than the VOVP1 due to low degree of transformer coupling or other

influences. please confirm by performing the evaluation of the actual application.

In addition, as a protection of Secondary output, ZTOVP is also available (case BM1Q021FJ). ZTOVP is described in (6).

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（3-2）VCC Recharge Function

After VCC (6pin) voltage > V_UVLO1,IC start to operate. After that, when VCC pin voltage < V_CHG1, VCC charge function is active.

Then starter circuit operates charge VCC (6pin) from VH line. By these, IC does not occur. When the IC charge the VCC pin

(6pin) and the VCC pin voltage exceeds V_CHG2,the charging function is finished.

The operation is shown to Figure-13.

Figure-13 VCC pin Charge Operation

A :As VH pin voltage（8pin）is rising, VCC pin(6pin) is started to charge by VCC charge function.

B: VCC pin （6pin） voltage > V_UVLO1,VCC UVLO function is released, VCC charge function is stopped, DC/DC operation start.

C: VCC pin (6pin) voltage is dropped for starting operation because OUTPUT voltage is low.

D: VCC pin （6pin） voltage < V_CHG1,VCC pin(6pin) voltage rises to operate charge function.

E: VCC pin （6pin） voltage > V_CHG2,VCC charge function stops.

F: VCC pin （6pin） voltage < V_CHG1,VCC pin (6pin) voltage rises to re-operate charge function.

G: VCC pin （6pin） voltage > V_CHG2,VCC charge function stops.

H: OUTPUT voltage is stable. Then, VCC pin (6pin) voltage is also stable for charging from the auxiliary winding to VCC

pin(6pin).

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( 4 ) DC/DC Driver

The IC operates PFM (Pulse Frequency Modulation) mode method.

By monitoring FB pin(2pin) and ZT pin (1pin), CS pin(3pin), the IC supply optimum system for DC/DC operation.

The IC controls ON width (Turn Off) of external MOSFET by FB pin (2pin) and CS pin (3pin). The IC controls OFF width (Turn

ON) of external MOSFET by ZT pin（1pin）. The detail is shown below.

(4-1) For QR-basic Operations

The QR basic block diagram and the basic operation are shown in Figure-14,15.

VOUT

Izt =(VH*Na)/(Np*Rzt1)

VCC

NOUT

12V Clamp

Circuit

ZT ACSNS Comp.

ZT OVP Comp.

(LATCH)

Rzt1

1 shot

Comp.

TimeOut

15 usec

5 usec

AND

Czt

POUT

SET

Rzt2

ZT Blanking

OUT(H->L)

0.60us

100mV

/200mV

AND

NOUT

PRE

Driver

OUT

AND

FBOLP_OH

AND

NOUT

Max frequency

control

VREF(4V)

RESET

30k

Burst

Comp.

VREF(4V)

0.5V

Cfb

OLP1

OLP2

1MΩ

FBOLP_OH

Timer

(64ms)

Soft Start

DCDC

Comp.

300kΩ

100kΩ

FB/4

0.5ms 1ms 2ms 4ms

0.50V

CURRENT SENSE (V-V Change)

Normal : ×1.0

Leading Edge

Blanking

GND

Figure-14 DC/DC Operation Block

Figure-15 QR Basic Operation

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For Figure-15

A: The internal oscillator outputs the SET signal, and turns ON the MOSFET.

At this time, the Drain - source capacitance of the MOSFET is discharged, so noise is generated to the CS pin.

This noise is called Leading Edge.

The filter for this noise is built in this IC. (It refer to (4-3))

Minimum pulse width of the IC is a 400ns (typ) by this filter and the delay time.

After that, current flows through the MOSFET, and Voltage Vcs = Rs * Ip is applied to the CS pin.

B: If CS pin voltage rises than FB pin voltage/Gain (typ = 4) or the overcurrent detection voltage Vcs,

RESET signal is output, OUT turns OFF

C: There is a delay time Tondelay from the point of B to turn OFF actually. Because of Tondelay the difference occurs in

the maximum power by the AC voltage. This IC has a built-in function to reduce this difference. (It refer to (4-4))

D: The energy stored in the transformer during Ton is discharged to the secondary side, and Free vibration of the Drain

voltage caused by the Cds (Drain - source capacitance) of MOSFET and Lp(transformer value) begins.

E: Since the switching frequency is determined by the IC.

SET signal is output from the internal oscillator and turn ON the MOSFET by process of certain time from A.

(4 -2) Determination of ON Width（Turn OFF）

ON width is controlled by FB (2pin), CS (3pin).

By comparison between FB pin voltage divided by AVcs (typ=4) and CS pin voltage, the IC decides ON width.

Besides, by comparison with Vlim1（typ =0.5V）voltage which is generated in IC, CS comparator level is changed lineally to be

shown in Figure-16(bottom). Maximum frequency also changes at this time.

CS (3pin) is shared with over current limiter circuit by pulse.

IC is changed over current limiter level and max frequency by FB (2pin) voltage.

・mode1 : Burst operation

・mode2 : Frequency reduction operation（reduce max frequency）

・mode3 : Max frequency operation (120kHz)

・mode4 : Over load operation（To detect over load state, IC is stopped switching）

MAX Fsw[kHz]

mode1

mode2

mode3

mode4

120kHz

30kHz

0.0V

0.5V

1.25V

2.0V

2.8V

FB [V]

CS ꢀLimiter[V]

Vlim1

mode1

mode2

mode3

mode4

Vlim2

0.0V

0.5V

1.25V

2.0V

2.8V

FB [V]

Figure-16 FB pin Voltage - Over Current Limiter, Max Frequency Characteristics

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The ON width of ”Ton” is decided by CS Limiter level “VCS”

Ton = (Lp*Vcs)/(Vin*RS)

Lp: primary inductance value,Vin :VH voltage in Figure-14, RS: Sense resistor in Figure-14

To adjust over current limiter level, CS over current protection voltage is switched in soft-start, AC voltage.

Vlim1 and Vlim2 is changed below.

Table2 Over current protection voltage Detail

AC=100V

AC=230V

Soft start

Vlim1

Vlim2

Vlim1

Vlim2

start～0.5ms

0.5ms～1ms

1ms～2ms

2ms～4ms

4ms～

0.063V ( 12%)

0.125V ( 25%)

0.250V ( 50%)

0.375V ( 75%)

0.500V (100%)

0.016V ( 3%)

0.032V (6%)

0.063V (12%)

0.094V (19%)

0.125V (25%)

0.044V (10%)

0.088V (20%)

0.175V (40%)

0.263V (60%)

0.350V (70%)

0.011V ( 2%)

0.022V ( 4%)

0.044V ( 9%)

0.066V ( 13%)

0.088V (18%)

* ( percent) is shown comparative value with Vlim1（typ =0.5V）in normal operation.

The reason that distinguish between AC100V and AC230V is by CS over current protection voltage switch function which

is shown to（4-4）.

(4-3) LEB（Leading Edge Blanking） Function

When a MOSFET for switching is turned ON, surge current occurs in cause of capacitance or rush current.

Therefore, when CS (3pin) voltage rises temporarily, over current limiter circuit may miss detections.

To prevent miss detections, the IC build-in blanking function which mask for T_LEB（typ=250ns） from switching OUT pin(5pin)

from L to H. This blanking function enables to reduce noise filter of CS pin(3pin).

However, when CS pin noise does not converge less than 250ns, need to attach RC filter to CS pin shown in Figure-17.

Then, delay time occurs to CS pin detection by RC filter.

Also, even if the filter in not attached, it is recommended that it is attached an Rcs resistor to CS pin as surge provision.

Rcs recommended resistor value is about 1kΩ.

Figure-17. CS pin surrounding circuit

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(4-4) CS Over Current Protection Switching Function

When input voltage（VH） is higher, ON time is short, and the operating frequency increases. As a result, maximum capable

power increases for constant over current limiter. For that, monitoring input voltage (VH), IC switches over current detection of

IC.

In case of high voltage（AC230V）, IC changes over current comparator level to ×0.7 multiple of normal level.

The detection method is that IC monitors ZT input current, then, IC switches it.

When MOSFET turns on, the voltage of “Va” has negative voltage to be affected input voltage (VH）.

Then, ZT (1pin) voltage is clamped near 0V by IC, ZT pin flows current to bias coil.

The calculation is below. And show block figure to Figure-18, show graph to Figure-19, Figure-20.

Izt ＝（Va－Vzt）/Rzｔ1 ≒ Va/Rzｔ1 ＝ VH * Na/Np /Rzｔ1

Rzt1 ＝ Va/Izt

Please set ZT current” Izt” to select the resistor Rzt1. And set bottom detection timing to select Czt.

About ZT current, IC builds in ZT current hysteresis I_ZTHYS(typ=0.1mA) to prevent VH detection changing by input voltage.

NOUT

12V Clamp

Circuit

1 shot

TimeOut

15 usec

5 usec

AND

POUT

ZT Blanking

OUT(H->L)

0.60us

100mV

/200mV

AND

NOUT

PRE

Driver

FBOLP_OH AND

AND

NOUT

Max frequency

control

30k

0.5V

1MΩ

FBOLP_OH

Timer

(64ms)

Soft Start

300kΩ

100kΩ

FB/4

SS SS

0.50V

0.5ms 1ms 2ms 4ms

CURRENT SENSE (V-V Change)

Normal : ×1.0

Leading Edge

Blanking

Figure-18 CS Over Current Detection Switched ZT current block diagram

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Limiter[V]

Vlim1

Vlim1*0.7

0.9mA 1.0mA

Izt[mA]

Figure-19 FB pin Voltage vs CS pin Voltage Characteristics

Figure-20 Izt Current vs Switched CS Voltage Characteristics

ex) setting method （Switching between AC100V and AC220V ）

AC100V: 141V±28V（±20% margin）

AC220V: 308V±62V（±20% margin）

In above case, need to switch CS over current detection voltage from 182V to 246V.

For that, switching VH voltage from AC100V to AC220V may be selected in VH＝214V.

Setting Np=100, Na=15

Va=Vin*Na/Np = 214V*15/100 *(-1) = -32.1V

Rzc = Va/ I_ZT= -32.1V/-1mA = 32.1kΩ

Therefore, set to Rzt=32KΩ

(4-5) Determination of OFF Width（Turn on）

OFF width is controlled at the ZT pin. When OUT is Low, the power stored in the coil is supplied to the secondary-side output

capacitor. When this power supply ends, there is no more current flowing to the secondary side, so the drain voltage of

switching MOSFET drops. Consequently, the voltage on the auxiliary winding side also drops. A voltage that was

resistance-divided by Rzt1 and Rzt2 is applied to ZT pin. When this voltage level drops to V_ZT1(100 mV typ) or below, MOSFET

is turned ON by the ZT comparator. Since zero current status is detected at the ZT pin, time constants are generated using Czt,

Rzt1, and Rzt2.

However, since Rzt1 and Rzt2 setting is required in AC voltage compensation function and ZTOVP function, bottom time

adjustment is set in Czt capacitor.

OFF time is calculated below equation:

Toff1=Ls/(Vout+VF)*Is

(Toff1 : transformer discharge time,Ls : secondary inductance ,Vout : Secondary output,

VF：secondary diode forward voltage,Is：secondary peak current）

For that, switching frequency is calculated below:

switching frequency = 1 / {transformer charge and discharge time(Ton+Toff1) + (bottom-1) × resonant time }

resonant time

1 / (2×π×√(Lp×Cds) )

＊Lp: primary inductance , MOSFET D-S capacitor : Cds

Because frequency reduction range in light load restricts shown Figure-16, bottom detection operates by the frequency which is

lower than max frequency function in Figure-16.

Additionally, a ZT trigger mask function (described in section 4-6) and a ZT timeout function (described in section 4-7) are built in

IC.

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(4-6) ZT Trigger Mask Function（Figure-22）

When switching is set from ON to OFF, superposition of noise may occur at the ZT pin.

Then, the ZT comparator and ZTOVP comparator are masked for the T_ZTMASKtime to prevent ZT comparator operation errors.

Figure-21 ZT Trigger Mask Function

A: DC/DC OFF=>ON

B: DC/DC ON=>OFF then the surge noise occurs to ZT pin.

C: Since a noise occurs to ZT pin at B, IC masks ZT comparator and ZTOVP comparator detection for T_ZTMASKtime.

(4-7-1) ZT Timeout Function1 （Figure-23）

When ZT pin voltage is not higher than V_ZT2(typ=200mV) for T_ZTOUT1(typ=15us) such as start or low output voltage, ZT pin short,

IC turns on MOSFET by force.

(4-7-2) ZT Timeout Function2 （Figure-23）

After ZT comparator detects bottom, when IC does not detect next bottom within T_ZTOUT2（typ =5us）, IC turns on MOSFET

by force. After ZT comparator detects bottom at once, the function operates. For that, it does not operate at start or at low output

voltage. When IC is not able to detect bottom by decreasing auxiliary winding voltage, the function operates.

ZT pin GND

short

V_ZT2

ZT V_ZT1

Bottom

detection

5us

timeout

15us

timeout

OUT

B C

Figure-22 ZT Timeout Function

A: When starting, IC starts to operate by ZT timeout function1 for ZT=0V.

B: MOSFET turns ON

C: MOSFET turns OFF

D: ZT voltage is lower than V_ZT2(typ=200mV) by ZT dump decreasing.

E: MOSFET turns ON by ZT timeout fucntion2 after T_ZTOUT2(typ=5us) from D point.

F: ZT voltage is lower than V_ZT2(typ=200mV) by ZT dump decreasing.

G: MOSFET turns ON by ZT timeout fucntion2 after T_ZTOUT2(typ=5us) from F point.

H: ZT pin is short to GND.

I : MOSFET turns ON by ZT timeout function1 after T_ZTOUT1(typ=15us)

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（5）Soft Start Sequence

Normally, when AC voltage is applied, a large current flows. Then secondary output voltage and current is occurred overshoot.

For preventing it, IC built in soft-start function.

When VCC pin(6pin) voltage is lower than V_UVLO2（typ =8.2V）, IC is reset. After that, when AC voltage is applied, IC operates

soft-start.

The soft start function is below: （ Please refer to (4-1) turn off item about CS limiter.）

・start ～ 0.5ms => Set CS limiter to 12.5% of normal operation.

・0.5ms～1ms

・1ms～2ms

・2ms～4ms

・4ms～

=> Set CS limiter to 25% of normal operation.

=> Set CS limiter to 50% of normal operation.

=> Set CS limiter to 75% of normal operation.

=> normal operation

（6）ZT pin (1pin) OVP (Over Voltage Protection : Only BM1Q021FJ )

IC build-in OVP function to ZT (1pin). IC detect ZTOVP protection, switching is stopped for T_ZTOVP(typ=512ms). After this time,

IC restart switching. ZTOVP operates by DC voltage detection and pulse detection for ZT pin.

・DC voltage detection

When ZT pin(1pin) voltage is over V_ZTL(typ=5.0V) until T_MASK(typ=100us), switching is stopped.

・Pulse detection

When the pulse of ZT (1pin) voltage larger than V_ZTL(typ=5.0V) is applied 3 count and for T_MASK（typ=100us）time, switching is

stopped

Figure-23 ZTOVP protection (pulse detection)

A: When OUT (5pin) voltage is changed from H to L, ZT (1pin) voltage is up. Then, surge pulse occurs to ZT (1pin). For that,

because IC builds in Tztmask time (typ=0.6us), IC does not detect ZTOVP for Tztmask time.

B: After Tztmask time (typ=0.6us), ZT OVP detects over voltage.

C: When ZTOVP comparator counts 3 pulse, T_MASKtimer (typ=100us) operates.

D: When it takes for 100us from C, IC detects ZT OVP and switching is stopped.

E: Switching is restarted after T_ZTOVP(typ=512ms) time .

It shows ZT OVP voltage setting method below. (auxiliary winding voltage : Va,ZT upper resistor : Rzt1,ZT lower resistor : Rzt2)

Secondary voltage : Vo, transformer winding ratio(secondary / auxiliary) : Ns/Na, ZT input current : IZT

The voltage which detects over voltage protection in secondary side : VOVP

VOVP = (Na/Ns)*Va = (Na/Ns) *{VZT*(Rzt1+Rzt2)/Rzt2+Rzt1*IZT}

When ZT voltage = 5.35V, ZT input current is calculated to IZT(max)=28uA,OVP maximum voltage is set below:

VOVP(max)=(Na/Ns)/｛5.35*(Rzt1+Rzt2)/Rzt2+Rzt2*28uA｝

Rzt1 setting is decided by AC voltage compensation function of (4-4).

Rzt2 setting is calculated below

Rzt2= Vztovp×Rzt1/{Vovp×(Na/Ns)-Izt×Rzt1-Vztovp}

BM1Q041FJ don’t have ZTOVP function.

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(7) CS (3pin) Open Protection

When CS （3pin） is OPEN, to prevent OUT pin from changing to H by noise, IC builds in CS(3pin) open protection.

When CS (3pin) is open, OUT (5pin) switching is stopped by the function. （This is auto-recovery）

VCCOVP

Timeout

Bottom det

POUT

AND

PRE

Driver

OUT

AND

FBOLP_OH

NOUT

VREF(4V)

1MΩ

CURRENT SENSE

(V-V Change)

Leading

Edge

Blanking

Normal :

×1.0

Figure-24 CS Open Protection

(8) OUTPUT Over Load Protection（FB OLP comparator）

When secondary output is over load, IC detects it by FB (2pin), IC stops switching.

In OLP state, because secondary photo-coupler is not flown current, FB (2pin) voltage is up.

When the condition continues for T_FOLP（typ =64ms）, IC judges over load state, OUT (5pin) is L fixed. After FB（2pin） voltage is

over V_FOLP1A（typ =2.8V）, when FB (2pin) voltage is lower than V_FOLP1B（typ =2.6V） within T_FOLP（typ =64ms）, over load

protection timer is reset.

In starting, because FB (2pin) is pull-up by a resistor to internal voltage, FB (2pin) voltage starts to operate in the state which is

more than V_FOLP1A（typ =2.8V）.

For that, please set stable time of secondary output voltage within T_FOLP（typ =64ms）.

After detecting over load, IC is stopped for T_OLPST（typ =512ms）,IC is auto-recovery operation.

In stopping switching, though VCC (6pin) voltage falls, but IC operates re-charge function by starter circuit, VCC (6pin) voltage

keeps VCC pin voltage > V_UVLO2

V_FOLP1A

VH charge

Switching

charge

512ms

charge

512ms

64ms

V_UVLO1

V_CHG2

V_CHG1

VCC

V_UVLO2

G H

Fg-25 Over Load Protection : Auto-recovery

A: When FB voltage is over V_FOLP1A(typ=2.8V), FBOLP comparator detects over load.

B: When the state A continues for T_FOLP（typ=64ms）, IC stops switching by over load protection.

C: During stopping switching by over load protection, VCC (6pin) voltage drops. When VCC（6pin） voltage is lower than V_CHG1

VCC re-charge function operate, VCC (6pin) voltage is up.

D: When VCC (6pin) voltage is higher than V_CHG2by re-charge function, VCC recharge function is stopped.

E: From B, it takes for T_OLPST（typ =512ms）, IC starts switching with soft-start.

F: When over load state continues, FB (2pin) voltage is over V_FOLP1A. When it takes for T_FOLP（typ=64ms） from E, IC stops

switching.

G: During stopping switching by over load protection, VCC (6pin) voltage drops. When VCC（6pin） voltage is lower than V_CHG1

VCC re-charge function operate, VCC (6pin) voltage is up.

H: When VCC (6pin) voltage is higher than V_CHG2by re-charge function, VCC recharge function is stopped.

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(9) OUT（5pin）Voltage Clamp Function

By the purpose which protects external MOSFET, H level of OUT （5pin） is clamped to V_OUTH（typ=12.5V）

It prevents gate destruction of MOSFET by rising VCC （6pin） voltage. （It refers to Figure-26）

OUT （5pin） is pull-down R_PDOUT(typ=100kΩ).

12V Clamp

Circuit

POUT

PRE

Driver

NOUT

Figure-26 OUT（5pin）Construction

Operation Mode of Protection Circuit

Operation mode of protection functions are shown in table3.

Table3 Operation Mode of Protection Circuit

Item

BM1Q021FJ

Self restart

BM1Q041FJ

Self restart

VCC Under Voltage Locked Out

VCC Over Voltage Protection

Self restart

FB Over Load Protection

CS Open Protection

(64ms delay, 512ms stop)

Self restart

ZT Over Voltage Protection

VCC Charge Protection

(100us delay, 512ms stop)

None

Self restart

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Power Dissipation

The thermal design should set operation for the following conditions.

(Since the temperature shown below is the guaranteed temperature, be sure to take a margin into account.)

1. The ambient temperature Ta must be 105℃ or less.

2. The IC’s loss must be within the allowable dissipation Pd.

The thermal abatement characteristics are as follows.

(PCB: 70 mm × 70 mm × 1.6 mm, mounted on glass epoxy substrate)

1000

900

800

700

600

500

400

300

200

100

125

100

150

Ta[

]

℃

Figure-27 SOP-J8 Thermal Abatement Characteristics

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Operational Notes

Reverse Connection of Power Supply

Connecting the power supply in reverse polarity can damage the IC. Take precautions against reverse polarity when

connecting the power supply, such as mounting an external diode between the power supply and the IC’s power

supply terminals.

Power Supply Lines

Design the PCB layout pattern to provide low impedance supply lines. Separate the ground and supply lines of the

digital and analog blocks to prevent noise in the ground and supply lines of the digital block from affecting the analog

block. Furthermore, connect a capacitor to ground at all power supply pins. Consider the effect of temperature and

aging on the capacitance value when using electrolytic capacitors.

Ground Voltage

Except for pins the output and the input of which were designed to go below ground, ensure that no pins are at a

voltage below that of the ground pin at any time, even during transient condition.

Ground Wiring Pattern

When using both small-signal and large-current ground traces, the two ground traces should be routed separately but

connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal

ground caused by large currents. Also ensure that the ground traces of external components do not cause variations

on the ground voltage. The ground lines must be as short and thick as possible to reduce line impedance.

Thermal Consideration

Should by any chance the power dissipation rating be exceeded, the rise in temperature of the chip may result in

deterioration of the properties of the chip. The absolute maximum rating of the Pd stated in this specification is when

the IC is mounted on a 70mm x 70mm x 1.6mm glass epoxy board. In case of exceeding this absolute maximum

rating, increase the board size and copper area to prevent exceeding the Pd rating.

Recommended Operating Conditions

These conditions represent a range within which the expected characteristics of the IC can be approximately obtained.

The electrical characteristics are guaranteed under the conditions of each parameter.

Rush Current

When power is first supplied to the IC, it is possible that the internal logic may be unstable and inrush current may

flow instantaneously due to the internal powering sequence and delays, especially if the IC has more than one power

supply. Therefore, give special consideration to power coupling capacitance, power wiring, width of ground wiring, and

routing of connections.

Operation Under Strong Electromagnetic Field

Operating the IC in the presence of a strong electromagnetic field may cause the IC to malfunction.

Testing on Application Boards

When testing the IC on an application board, connecting a capacitor directly to a low-impedance output pin may

subject the IC to stress. Always discharge capacitors completely after each process or step. The IC’s power supply

should always be turned off completely before connecting or removing it from the test setup during the inspection

process. To prevent damage from static discharge, ground the IC during assembly and use similar precautions during

transport and storage.

10. Inter-pin Short and Mounting Errors

Ensure that the direction and position are correct when mounting the IC on the PCB. Incorrect mounting may result in

damaging the IC. Avoid nearby pins being shorted to each other especially to ground, power supply and output pin.

Inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and

unintentional solder bridge deposited in between pins during assembly to name a few.

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Operational Notes – continued

11. Unused Input Terminals

Input terminals of an IC are often connected to the gate of a MOS transistor. The gate has extremely high impedance

and extremely low capacitance. If left unconnected, the electric field from the outside can easily charge it. The small

charge acquired in this way is enough to produce a significant effect on the conduction through the transistor and

cause unexpected operation of the IC. So unless otherwise specified, unused input terminals should be connected to

the power supply or ground line.

12. Regarding the 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 the P layers with the N layers of other elements, creating a

parasitic diode or transistor. For example (refer to figure below):

When GND > Pin A and GND > Pin B, the P-N junction operates as a parasitic diode.

When GND > Pin B, the P-N junction operates as a parasitic transistor.

Parasitic diodes inevitably occur in the structure of the IC. The operation of parasitic diodes can result in mutual

interference among circuits, operational faults, or physical damage. Therefore, conditions that cause these diodes to

operate, such as applying a voltage lower than the GND voltage to an input pin (and thus to the P substrate) should

be avoided.

Example of monolithic IC structure

13. Ceramic Capacitor

When using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with

temperature and the decrease in nominal capacitance due to DC bias and others.

14. Area of Safe Operation (ASO)

Operate the IC such that the output voltage, output current, and power dissipation are all within the Area of Safe

Operation (ASO).

15. Thermal Shutdown Circuit(TSD)

This IC has a built-in thermal shutdown circuit that prevents heat damage to the IC. Normal operation should always

be within the IC’s power dissipation rating. If however the rating is exceeded for a continued period, the junction

temperature (Tj) will rise which will activate the TSD circuit that will turn OFF all output pins. When the Tj falls below

the TSD threshold, the circuits are automatically restored to normal operation.

Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no

circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from

heat damage.

16. Over Current Protection Circuit (OCP)

This IC incorporates an integrated overcurrent protection circuit that is activated when the load is shorted. This

protection circuit is effective in preventing damage due to sudden and unexpected incidents. However, the IC should

not be used in applications characterized by continuous operation or transitioning of the protection circuit.

Status of this document

The Japanese version of this document is formal specification. A customer may use this translation version only for a reference

to help reading the formal version.

If there are any differences in translation version of this document formal version takes priority

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BM1Q021FJ/BM1Q041FJ

Ordering Information

B M 1 Q 0 X

E 2

Package

FJ – SOP-J8

Product name

Packaging and

forming specification

E2: Embossed tape and reel

Marking Diagram

Line Up

Product(BM1Q0X1FJ)

BM1Q021FJ

BM1Q041FJ

1PIN MARK

1Q0X1

LOT No.

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TSZ22111・15・001

TSZ02201-0F1F0A200280-1-2

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BM1Q021FJ/BM1Q041FJ

Physical Dimension Tape and Reel Information

Package Name

SOP-J8

Tape

Embossed carrier tape

2500pcs

Quantity

Direction

of feed

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

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

(

)

Direction of feed

1pin

Reel

Order quantity needs to be multiple of the minimum quantity.

∗

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BM1Q021FJ/BM1Q041FJ

Revision History

Date

Revision

001

Changes

New Release

27.Sep.2016

www.rohm.com

TSZ02201-0F1F0A200280-1-2

27.Sep.2016 Rev.001

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TSZ22111・15・001

Notice

Precaution on using ROHM Products

1. Our Products are designed and manufactured for application in ordinary electronic equipments (such as AV equipment,

OA equipment, telecommunication equipment, home electronic appliances, amusement equipment, etc.). If you

intend to use our Products in devices requiring extremely high reliability (such as medical equipment ^{(Note 1)}, transport

equipment, traffic equipment, aircraft/spacecraft, nuclear power controllers, fuel controllers, car equipment including car

accessories, safety devices, etc.) and whose malfunction or failure may cause loss of human life, bodily injury or

serious damage to property (“Specific Applications”), please consult with the ROHM sales representative in advance.

Unless otherwise agreed in writing by ROHM in advance, ROHM shall not be in any way responsible or liable for any

damages, expenses or losses incurred by you or third parties arising from the use of any ROHM’s Products for Specific

Applications.

(Note1) Medical Equipment Classification of the Specific Applications

JAPAN

USA

CHINA

CLASSⅢ

CLASSⅣ

CLASSⅡb

CLASSⅢ

2. ROHM designs and manufactures its Products subject to strict quality control system. However, semiconductor

products can fail or malfunction at a certain rate. Please be sure to implement, at your own responsibilities, adequate

safety measures including but not limited to fail-safe design against the physical injury, damage to any property, which

a failure or malfunction of our Products may cause. The following are examples of safety measures:

[a] Installation of protection circuits or other protective devices to improve system safety

[b] Installation of redundant circuits to reduce the impact of single or multiple circuit failure

3. Our Products are designed and manufactured for use under standard conditions and not under any special or

extraordinary environments or conditions, as exemplified below. Accordingly, ROHM shall not be in any way

responsible or liable for any damages, expenses or losses arising from the use of any ROHM’s Products under any

special or extraordinary environments or conditions. If you intend to use our Products under any special or

extraordinary environments or conditions (as exemplified below), your independent verification and confirmation of

product performance, reliability, etc, prior to use, must be necessary:

[a] Use of our Products in any types of liquid, including water, oils, chemicals, and organic solvents

[b] Use of our Products outdoors or in places where the Products are exposed to direct sunlight or dust

[c] Use of our Products in places where the Products are exposed to sea wind or corrosive gases, including Cl2,

H2S, NH3, SO2, and NO2

[d] Use of our Products in places where the Products are exposed to static electricity or electromagnetic waves

[e] Use of our Products in proximity to heat-producing components, plastic cords, or other flammable items

[f] Sealing or coating our Products with resin or other coating materials

[g] Use of our Products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of

flux is recommended); or Washing our Products by using water or water-soluble cleaning agents for cleaning

residue after soldering

[h] Use of the Products in places subject to dew condensation

4. The Products are not subject to radiation-proof design.

5. Please verify and confirm characteristics of the final or mounted products in using the Products.

6. In particular, if a transient load (a large amount of load applied in a short period of time, such as pulse. is applied,

confirmation of performance characteristics after on-board mounting is strongly recommended. Avoid applying power

exceeding normal rated power; exceeding the power rating under steady-state loading condition may negatively affect

product performance and reliability.

7. De-rate Power Dissipation depending on ambient temperature. When used in sealed area, confirm that it is the use in

the range that does not exceed the maximum junction temperature.

8. Confirm that operation temperature is within the specified range described in the product specification.

9. ROHM shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in

this document.

Precaution for Mounting / Circuit board design

1. When a highly active halogenous (chlorine, bromine, etc.) flux is used, the residue of flux may negatively affect product

performance and reliability.

2. In principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method must

be used on a through hole mount products. If the flow soldering method is preferred on a surface-mount products,

please consult with the ROHM representative in advance.

For details, please refer to ROHM Mounting specification

Notice-PGA-E

Rev.003

Precautions Regarding Application Examples and External Circuits

1. If change is made to the constant of an external circuit, please allow a sufficient margin considering variations of the

characteristics of the Products and external components, including transient characteristics, as well as static

characteristics.

2. You agree that application notes, reference designs, and associated data and information contained in this document

are presented only as guidance for Products use. Therefore, in case you use such information, you are solely

responsible for it and you must exercise your own independent verification and judgment in the use of such information

contained in this document. ROHM shall not be in any way responsible or liable for any damages, expenses or losses

incurred by you or third parties arising from the use of such information.

Precaution for Electrostatic

This Product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. Please take proper

caution in your manufacturing process and storage so that voltage exceeding the Products maximum rating will not be

applied to Products. Please take special care under dry condition (e.g. Grounding of human body / equipment / solder iron,

isolation from charged objects, setting of Ionizer, friction prevention and temperature / humidity control).

Precaution for Storage / Transportation

1. Product performance and soldered connections may deteriorate if the Products are stored in the places where:

[a] the Products are exposed to sea winds or corrosive gases, including Cl2, H2S, NH3, SO2, and NO2

[b] the temperature or humidity exceeds those recommended by ROHM

[c] the Products are exposed to direct sunshine or condensation

[d] the Products are exposed to high Electrostatic

2. Even under ROHM recommended storage condition, solderability of products out of recommended storage time period

may be degraded. It is strongly recommended to confirm solderability before using Products of which storage time is

exceeding the recommended storage time period.

3. Store / transport cartons in the correct direction, which is indicated on a carton with a symbol. Otherwise bent leads

may occur due to excessive stress applied when dropping of a carton.

4. Use Products within the specified time after opening a humidity barrier bag. Baking is required before using Products of

which storage time is exceeding the recommended storage time period.

Precaution for Product Label

A two-dimensional barcode printed on ROHM Products label is for ROHM’s internal use only.

Precaution for Disposition

When disposing Products please dispose them properly using an authorized industry waste company.

Precaution for Foreign Exchange and Foreign Trade act

Since concerned goods might be fallen under listed items of export control prescribed by Foreign exchange and Foreign

trade act, please consult with ROHM in case of export.

Precaution Regarding Intellectual Property Rights

1. All information and data including but not limited to application example contained in this document is for reference

only. ROHM does not warrant that foregoing information or data will not infringe any intellectual property rights or any

other rights of any third party regarding such information or data.

2. ROHM shall not have any obligations where the claims, actions or demands arising from the combination of the

Products with other articles such as components, circuits, systems or external equipment (including software).

3. No license, expressly or implied, is granted hereby under any intellectual property rights or other rights of ROHM or any

third parties with respect to the Products or the information contained in this document. Provided, however, that ROHM

will not assert its intellectual property rights or other rights against you or your customers to the extent necessary to

manufacture or sell products containing the Products, subject to the terms and conditions herein.

Other Precaution

1. This document may not be reprinted or reproduced, in whole or in part, without prior written consent of ROHM.

2. The Products may not be disassembled, converted, modified, reproduced or otherwise changed without prior written

consent of ROHM.

3. In no event shall you use in any way whatsoever the Products and the related technical information contained in the

Products or this document for any military purposes, including but not limited to, the development of mass-destruction

weapons.

4. The proper names of companies or products described in this document are trademarks or registered trademarks of

ROHM, its affiliated companies or third parties.

Notice-PGA-E

Rev.003

Daattaasshheeeett

General Precaution

1. Before you use our Pro ducts, you are requested to care fully read this document and fully understand its contents.

ROHM shall not be in an y way responsible or liable for failure, malfunction or accident arising from the use of a ny

ROHM’s Products against warning, caution or note contained in this document.

2. All information contained in this docume nt is current as of the issuing date and subj ect to change without any prior

notice. Before purchasing or using ROHM’s Products, please confirm the la test information with a ROHM sale s

representative.

3. The information contained in this doc ument is provi ded on an “as is” basis and ROHM does not warrant that all

information contained in this document is accurate an d/or error-free. ROHM shall not be in an y way responsible or

liable for any damages, expenses or losses incurred by you or third parties resulting from inaccuracy or errors of or

concerning such information.

Notice – WE

Rev.001

BM1Q021FJ [ROHM]

相关型号：

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BM1R00002-E2

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BM1R00006-E2

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