BD95841MUV [ROHM]

BD95841MUV是可在输入电压范围(7.5V～15V)内通过大电流输出实现输出电压(0.8V～5.5V)的1ch降压开关稳压器。通过内置开关晶体管用的N-MOSFET，可实现省空间的高效同步整流开关稳压器。采用H3Reg™罗姆的ONTIME固定控制模式，无需相位补偿部件，即可实现高速瞬态响应特性。具有软启动功能、Power Good功能、带计时锁存的短路输出 / 过电压保护电路功能，适用于数字AV设备用电源。;


型号：	BD95841MUV
厂家：	ROHM
描述：	BD95841MUV是可在输入电压范围(7.5V～15V)内通过大电流输出实现输出电压(0.8V～5.5V)的1ch降压开关稳压器。通过内置开关晶体管用的N-MOSFET，可实现省空间的高效同步整流开关稳压器。采用H3Reg™罗姆的ONTIME固定控制模式，无需相位补偿部件，即可实现高速瞬态响应特性。具有软启动功能、Power Good功能、带计时锁存的短路输出 / 过电压保护电路功能，适用于数字AV设备用电源。开关软启动晶体管稳压器
文件：	总26页 (文件大小：777K)
中文：	中文翻译
下载：	下载PDF数据表文档文件

Datasheet

7.5V to 15V, 4A Integrated MOSFET

1ch Synchronous Buck DC/DC Converter

BD95841MUV

●Description

BD95841MUV is a 1ch synchronous buck converter that

●Features

・Input Voltage Range:

7.5V to 15.0V

0.8V±1.5%

0.8V to 5.5V

can generate output voltage (0.8V to 5.5V) at the input

voltage range (7.5V to 15V). Space-saving and high

efficient switching regulator can be achieved due to

built-in N-MOSFET power transistors. The IC also

incorporates H³Reg^TMtechnology, a Rohm proprietary

constant ON TIME control mode which facilitates

ultra-high transient response against changes in load

without external compensation components. Fixed soft

start function, power good function, and short circuit /

over voltage protection with timer latch functions are

incorporated. The BD95841MUV is designed for power

supplies for Digital AV Equipment.

・Reference Voltage:

・Output Voltage Range:

・Output Current:

・Switching Frequency:

（depend on input-output condition）

・Built-in Power MOS FET

4.0A (Max.)

500kHz to 800kHz

High-side Nch FET ON resistance:

Low-side Nch FET ON resistance:

65mΩ(typ.)

45mΩ(typ.)

・Fast Transient Responses due to H³Reg control

・Over Current Protection (OCP) – Cycle-by-Cycle

・Thermal Shut Down (TSD)

・Under-Voltage Lock-Out (UVLO)

・Short Circuit Protection (SCP)

・Over Voltage Protection (OVP)

・Fixed Soft Start (1msec ; typ)

●Applications

・LCD TVs

・Set Top Boxes (STB)

・DVD/Blu-ray players/recorders

・Broadband Network and Communication Interface

・Amusement, other.

・Power Good function

●Package

・VQFN016V3030

W(Typ.) x D(Typ.) x H(Max.)

3.0mm x 3.0mm x 1.0mm

●Pin Configuration (TOP VIEW)

●Typical Application

PGOOD EN

BOOT

GND

VREG

GND

VREG

TEST

BOOT

TEST

VIN

GND

Thermal Pad

GND

VIN

VOUT

Figure 1. Typical Application Circuit

Figure 2. Pin Configuration

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

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●Block Diagram

Figure 3. Block Diagram

●Pin Description

No.

Symbol

Description

Input Voltage Supply pin.

The IC determines the duty cycles internally based on the input voltage. Therefore, variations of

VIN pin can lead to unstable operation. This pin also acts as the input voltage to the internal

switching regulator output block, and is sensitive to the impedance of the power supply.

Connect over 10F ceramic capacitors for the decoupling capacitors to PGND as near as these

pins.

1, 2, 16

VIN

3, 4

5, 6, 7

PGND

Power ground pin connected to the source of the Low side FET.

Switch node connection between High side FET source and Low side FET drain.

Connect 0.01μF capacitor between BOOT and SW. This pin is also connected to inductor (L).

High side FET Gate Driver Power Supply pin.

Connect 0.01μF capacitor between BOOT and SW.

BOOT voltage swings from VREG to (VIN + VREG) during normal switching operation.

BOOT

Enable Input pin.

When the input voltage of the EN pin reaches at least 2.2V, the switching regulator becomes

active. At the voltage less than 0.3 V, the IC becomes standby mode.

Open-drain Power Good Output pin.

PGOOD

Due to the open-drain output, a 100kΩ pull-up resistor should be connected between this pin and

VREG or other power supply. In the case of no use, this pin is opened or shortened to ground.

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●Pin Description (Continued)

No.

Symbol

Description

Output Voltage Sense pin.

Connect to output voltage directly. ONTIME is determined by monitoring the output voltage.

VOUT

Output Voltage Feedback pin. FB is compared with REF in the IC. Please set the output voltage

in the feedback resistances of less than total 50kΩ. (Refer to page 15)

GND

VREG

TEST

Sense ground pin for all internal analog and digital power supplies.

Power supply output inside IC. When at least 2.2V is supplied to the EN pin, the VREG is active.

This pin supplies 5.0V at up to 10mA. Insert a 0.022μF capacitor between this pin and ground

pin.

TEST Pin. Connect to ground.

Thermal

Pad

Exposed Thermal Pad. Connect to ground.

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●Absolute Maximum Ratings (Ta=25℃)

Comment

Parameter

Symbol

VIN

Limit

15.2 *¹

21.5 *¹

7 *¹

Unit

Input Voltage

BOOT Voltage

BOOT

BOOT-SW Voltage

Output Voltage

BOOT-SW

VOUT

7 *¹

SW Voltage

15.2 *¹

VREG

7 *¹

Output Feedback Voltage

VREG Voltage

VREG

EN Input Voltage

PGOOD Voltage

Power Dissipation 1

Power Dissipation 2

15.2 *¹

7 *¹

PGOOD

Pd1

Ta ≧25°C (IC only), power dissipated at

0.27

2.2mW / °C.

Ta≧25°C (70mm×70mm×1.6mm single-layer

board, 6.28mm²copper heat dissipation pad),

power dissipated at 5.0mW / °C.

Pd2

0.62

Ta≧25°C (70mm×70mm×1.6mm 4-layer

board, 6.28 mm²copper heat dissipation pad

on top and bottom layer, 5505 mm²pad on 2^nd

and 3^rdlayer), power dissipated at 14.1mW

/ °C.

Ta≧25°C (70mm×70mm×1.6mm 4-layer

board, all layers with 5505 mm²copper heat

dissipation pads), power dissipated at

21.3mW / °C.

Power Dissipation 3

Power Dissipation 4

Pd3

Pd4

1.77

2.66

Operating Temperature Range

Storage Temperature Range

Junction Temperature

Topr

Tstg

-20 to +100 *¹

-55 to +150

+150

℃

Tjmax

Not to exceed Pd.

●Operating Ratings (Ta= -20 to 100℃)

Limit

Unit

Parameter

Symbol

Min

7.5

Typ

Max

VIN

VREG

BOOT

Input Voltage

4.5

-0.7

4.5

5.0

5.5

VREG Voltage

BOOT Voltage

SW Voltage

BOOT-SW

5.5

BOOT-SW Voltage

EN Input Voltage

Output Voltage

PGOOD Voltage

Minimum ON Time

VOUT ^*2

PGOOD

Tonmin

0.8

5.5

200

nsec

*2 VOUT depends on Input Voltage (VIN) in some cases.

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●Electrical Characteristics

(Unless otherwise noted Ta=25℃, VIN=12V, EN=3V, VOUT=3.3V)

Limit

Parameter

VIN Bias Current

Symbol

Unit

Condition

Min

Typ

Max

2.0

I_IN

1.2

I_{IN_STB}

A

EN=0V

VIN Standby Current

Enable Control

EN_LOW

EN_HIGH

I_EN

GND

2.2

0.3

EN Low Voltage

EN High Voltage

A

EN=3V

EN Bias Current

VREG Output Voltage

VREG Standby Voltage

VREG Output Voltage

Maximum Output Current

Power MOSFET

V_{REG_STB}

V_REG

5.0

0.1

5.5

EN=0V

4.5

I_REG=10mA

I_REG

High side FET ON Resistance

Low side FET ON Resistance

Reference Voltage

FB threshold Voltage

FB Input Current

R_ONH

R_ONL

130

mΩ

V_FB

I_FB

0.788

-1

0.800

0.812

A

H³Reg Control

T_ON

470

450

nsec

ON Time

T_OFFMIN

200

Minimum OFF Time

Soft Start / Output Discharge

Soft Start Time

T_SOFT

I_VOUT

1.0

6.6

msec

VOUT Discharge Current

mA VOUT=1V, EN=0V, V_REG=5V

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●Electrical Characteristics (Continued)

(Unless otherwise noted Ta=25℃, VIN=12V, EN=3V, VOUT=3.3V)

Limit

Parameter

Symbol

Unit

Condition

Min

4.5

Typ

Max

7.5

Over Current Protection

Current Limit

I_OCP

6.0

SCP

SCP Threshold Voltage

SCP delay time

V_SCP

T_SCP

0.48

0.56

1.0

0.64

V_FB=0.8V → 0V

V_FB=0.8V → 2.0V

VREG: Sweep up

msec

OVP

OVP Threshold Voltage

OVP delay time

V_OVP

T_OVP

0.86

0.96

1.0

1.06

msec

UVLO

VREG Threshold Voltage

VREG Hysteresis Voltage

Power Good

V_{REG_UVLO}

dV_{REG_UVLO}

3.75

100

4.20

160

4.65

220

mV VREG: Sweep down

V_FBPower Good Low Voltage

V_FBPower Good High Voltage

V_{FB_PL}

V_{FB_PH}

0.61

0.65

0.68

0.72

0.75

0.79

V_FB=0.8V → 0V

V_FB=0V → 0.8V

＊3 No tested on outgoing inspection.

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●Typical Performance Curves (Unless otherwise noted Ta=25℃, VIN=12V)

100

VOUT = 3.3V

VOUT = 5.0V

VOUT = 1.2V

Iout [A]

Figure 4. Efficiency

Figure 5. Tc – Iout

(VIN=12V, L=3.3H)

(VIN=12V, VOUT=3.3V, L=3.3H)

VOUT

(AC)

VOUT

(AC)

20mV/div

5V/div

1sec/div

Figure 6. VOUT Ripple voltage

(VIN=12V, VOUT=3.3V, L=3.3H, COUT=44F, Iout=0A)

Figure 7. VOUT Ripple voltage

(VIN=12V, VOUT=3.3V, L=3.3H, COUT=44F, Iout=4A)

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●Typical Performance Curves (Unless otherwise noted Ta=25℃, VIN=12V) (Continued)

3.45

3.40

3.35

3.30

3.25

3.20

3.15

3.45

3.40

3.35

3.30

3.25

3.20

3.15

Iout=0A

Iout=4A

VIN[V]

Iout [A]

Figure 8. VOUT Load Regulation

Figure 9. VOUT Line Regulation

(VIN=12V, VOUT=3.3V, L=3.3H)

(VOUT=3.3V, L=3.3H, Iout=0A / 4A)

3.40

800

750

700

650

600

550

500

3.35

3.30

3.25

3.20

-20

100

VIN [V]

Temperature [

]

℃

Figure 10. VOUT - Temperature

(VIN=12V, VOUT=3.3V, L=3.3H, Iout=0A)

Figure 11. Frequency - VIN

(VIN=12V, VOUT=3.3V, L=3.3H, Iout=0A)

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●Typical Performance Curves (Unless otherwise noted Ta=25℃, VIN=12V) (Continued)

5V/div

10V/div

VOUT

2V/div

VOUT

2V/div

PGOOD

5V/div

PGOOD

5V/div

200sec/div

10msec/div

Figure 12. Start up with EN

Figure 13. Power down with EN

(VIN=12V, VOUT=3.3V, L=3.3H, COUT=44F, Iout=0A)

VOUT

2V/div

VOUT (AC)

50mV/div

20V/div

Iout

2A/div

200sec/div

100sec/div

Figure 14. VOUT Transient Response

(VIN=12V, VOUT=3.3V, L=3.3H, COUT=44F)

Iout=0⇔2A (SR=1.0A/sec)

Figure 15. OCP function

(VIN=12V, VOUT=3.3V, L=3.3H, COUT=44F)

(VOUT is shorted to ground)

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●Explanation of Operation

The BD95841MUV is a 1ch synchronous buck converter incorporating ROHM’s proprietary H³Reg^TMCONTROLLA system.

When VOUT drops due to a rapid load change, the system quickly restores VOUT by increasing the frequency.

1. H³Reg^TMSystem

1-1. Normal Operation

When FB falls below the threshold voltage (REF), a drop is detected, activating the H³Reg^TMCONTROLLA system.

V_OUT

V_IN

[sec]

(1)

Ton





HG (Gate of High side MOSFET) output is determined by the formula (1). LG (Gate of Low side MOSFET) output operates

until FB voltage falls below REF voltage after HG becomes OFF. OFF time is restricted by MIN OFF Time (typ.:450nsec).

Hence, BD95841MUV runs with a constant on-time by using the input and output voltage to set the internal on-time timer.

1-2. VOUT drops due to a rapid load change

When FB (VOUT) drops due to a rapid load change and the voltage remains below REF, the system quickly restores

VOUT by shortening OFF time of HG (increasing the frequency), improving transient response as shown Figure 16 (b).

REF

(a) Normal operation

(b) Rapid load change

Figure 16. H³REG System

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●Timing Chart

1. Soft Start Function

Soft start is utilized when the EN pin is set high. Current control takes effect at startup, enabling a moderate “ramping start”

on the output voltage. Soft start time is 1.0msec (typ). Rush current is determined via formula (2) below.

C _OUT V_OUT

1.0msec

[A]

(2)

I_IN



C_OUT: All capacitors connected with VOUT

1.0msec (typ)

VOUT

I^IN

Figure 17. Soft Start Timing Chart

2. Power Good Function

When FB voltage is more than 0.72V (90%), the integrated open-drain NMOS is set to OFF, and PGOOD outputs High due

to pull-up register. If FB voltage falls below 0.68V (85%), PGOOD becomes Low.

0.72V

0.68V

PGOOD

Figure 18. Power Good Timing Chart

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●Protection Operation

1. OCP Operation

Normally, when FB voltage falls below REF voltage, HG becomes high. However, if the current through the inductor (I_L)

exceeds OCP current value (I_OCP) during LG=ON, HG does not become high and I_Lis restricted by I_OCP. When I_Lfalls down

below I_OCP, HG is stricken by the pulse width of Ton decided by formula (1). As the result, the output voltage can decrease

as the frequency and duty are changed.

When OCP is released in the state that the output has decreased by OCP operation, the output voltage might rise up due

to high-speed load response. Also OFF Latch is operated when FB voltage becomes below the SCP setting voltage during

1msec (typ.) (Refer to 2-1).

Figure 19. OCP Timing Chart

2. SCP Operation / OVP Operation (OFF Latch)

2-1. SCP Operation

SCP monitors FB voltage. When FB falls below 0.56V, after 1msec (typ.) later, the short circuit protection (SCP) operates,

turning the high side MOSFET and low side MOSFET OFF, and performs OFF latch operation.

2-2. OVP Operation

OVP monitors FB voltage. When FB exceeds 0.96V, after 1msec (typ.) later, the output over voltage protection (OVP)

operates, turning the high side FET OFF and the low side FET ON, and performs OFF latch operation.

2-3. Recovery from OFF Latch mode

Off latch is released by EN=OFF or UVLO operation, and then it returns to standard operation.

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Figure 20. SCP Timing Chart

FB > REF, HG=L

LG=H

0.96V

1msec(typ)

VREG

Latch Release

by EN or UVLO

Normal Operation

OVP

OFF Latch

Normal Operation

Stand by

Figure 21. OVP Timing Chart

3. TSD Operation (Self Recovery)

TSD is self-activating. If the junction temperature exceeds Tj = 175℃, and HG, LG, PGOOD, and SS become Low.

The IC becomes standby when TSD operating.

When Tj falls below 150℃, it returns to standard operation.

4. UVLO Operation

UVLO operates when VREG voltage falls below 4.05V, ad HG, LG, PGOOD and SS become Low.

The IC becomes standby when UVLO operating.

UVLO is released when VREG goes up to 4.2V, and starts standard operation

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●Selection of Components Externally Connected

1. Output LC Filter Selection (Buck Converter)

1-1. Inductor (L) Selection

The Output LC filter is required to supply constant current to the output load. A larger value inductance at this filter results

in less inductor ripple current (∆I_L) and less output ripple voltage. However, the larger value inductors tend to have less

fast load transient-response, a larger physical size, a lower saturation current and higher series resistance. A smaller

value inductance has almost opposite characteristics above.

The recommended inductor values are shown in Table 1(Refer to page 18).

The value of ΔI_Lis shown as formula (3).



V_IN V_OUT



 V_OUT

ΔI _L



[A]

(3)

L  f  V_IN

For example, with VIN = 12 V, VOUT = 3.3 V, L = 3.3H and the switching frequency f = 600 kHz, the calculated ripple

current ⊿IL is 1.2A.

Then, the inductor saturation current must be larger than the sum of the maximum output current (IOUTMAX) and 1/2 of

the inductor ripple current (∆IL / 2). A larger current than the inductor’s saturation current will cause magnetic saturation in

the inductor, and decrease efficiency. When selecting an inductor, be sure to allow enough margins to assure that peak

current does not exceed the inductor’s saturation current value.

※To minimize loss of inductor and improve efficiency, choose a inductor with a low resistance (DCR, ACR).

VIN

Inductor saturation current > I_OUTMAX+⊿I_L/2

⊿I_L

Average inductor current

VOUT

C_OUT

(Output Current：IOUT)

Figure 22. Inductor Ripple Current

1-2. Output Capacitor (C_OUT) Selection

Output Capacitor (C_OUT) has a considerable influence on output voltage regulation due to a rapid load change and

smoothing output ripple voltage. Determine the capacitor by considering the value of capacity, the equivalent series

resistance, and equivalent series inductance. Also, make sure the capacitor’s voltage rating is high enough for the set

output voltage (including ripple).

Output ripple voltage is determined as in formula (4) below.

ΔVOUT=ΔI_L/(8×C_OUT×f)+ESR×ΔI_L+ESL×ΔI_L/ Ton

[V]

(4)

(ΔI_LOutput ripple current、ESR: Equivalent series resistance、ESL: Equivalent series inductance)

Also, give consideration to the conditions in formula (5) below for output capacitance, bearing in mind that output rise

time must be established within the fixed soft start time. As output capacitance, bypass capacitor will be also connected

to output load side (C_EXT, Figure 23). Please set the over current detection value with regards to these capacitance.

1msec 



I_OCP I_OUT



C_OUT



[F]

(5)

V_OUT

(I_OCP: OCP Current Limit, I_OUT: Output Current)

Note: an improper output capacitor may cause startup malfunctions.

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VIN

VOUT

ESR

C_EXT

Load

ESL

C_OUT

Figure 23. Output Capacitor

2. Input Capacitor (CIN) Selection

VIN

In order to prevent transient spikes in voltage, the input capacitor should have a low

enough ESR resistance to fully support a large ripple current. The formula for ripple

current I_RMSis given in equation (6) as below.

CIN

VOUT

V_OUT(V  V_OUT

)

I_RMS I_OUT



[A]

(6)

C_OUT

IOUT

Where VIN =2×VOUT, IRMS=

A low ESR capacitor is recommended to reduce ESR loss and improve efficiency.

Figure 24. Input Capacitor

3. Output Voltage Setting

The IC controls output voltage as REF≒V_FB.

However, the actual output voltage will also reflect the average ripple voltage value.

The output voltage is set with a resistor divider from the output node to the FB pin. The formula for output voltage is given

in (7) below:

R1+R2

Output Voltage =

× REF +ΔVOUT

[V]

(7)

(8)

(9)

REF = VFB(TYP 0.8V) + 0.02 – (ON DUTY × 0.05)

VOUT

ON DUTY =

VIN

Please refer to eq. (4) regarding ΔVOUT.

VIN

REF

VFB

Output Voltage

VOUT

H³Reg^TM

CONTROLLA

Driver

Circuit

Figure 25. Output Voltage Setting

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4. Relationship between Output Voltage and ONTIME

BD95841MUV is a synchronous buck converter controlling constant ONTIME. The ONTIME (Ton) depends on the output

voltage settings, as described by the formula (10).

V_OUT

610

Ton  1770 



 55

[nsec]

(10)

The frequency of the application condition is determined by the formula (11) using the above Ton.

VOUT

VIN

Frequency =

[kHz]

(11)

Ton

However with actual applications, there exists a rising and falling time of the SW due to the gate capacitance of the

integrated MOSFET and the switching speed, which may vary the above parameters. Therefore please also verify those

parameters experimentally.

5. Relationship between Output Current and Frequency

BD95841MUV is a constant ontime type of switching regulator. When the output current increases, the switching loss of

the inductor, MOSFET, and output capacitor also increases. Hence the switching frequency speeds up.

The loss of the inductor, MOSFET, and output capacitor is determined as below.

① Loss of Inductor = IOUT²× DCR

② Loss of MOSFET (High Side) = IOUT²× R_ONH

VOUT

VIN

VOUT

VIN

③ Loss of MOSFET (Low Side) = IOUT²× R_ONL× (1 -

④ Loss of Output Capacitor = IOUT²× ESR

)

(DCR : Inductor Equivalent series resistance、R_ONH: On resistance of High-side MOSFET、R_ONL: On resistance of Low-side MOSFET、

ESR :COUT Equivalent series resistance)

Taking the above losses into the frequency equation, then T (=1/Freq) becomes

VIN × IOUT × Ton

T (=1/Freq) =

[nsec]

(12)

VOUT × IOUT + ① + ② + ③ + ④

However since the parasitic resistance of the PCB layout pattern exists in actual applications and affects the parameter,

please also verify experimentally.

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●PCB Layout Guide

Two high pulsing current flowing loops exist in the buck regulator system.

The first loop, when FET is ON, starts from the input capacitors, to the VIN terminal, to the SW terminal, to the inductor, to

the output capacitors, and then returns to the input capacitor through GND.

The second loop, when FET is OFF, starts from the low FET, to the inductor, to the output capacitor, and then returns to the

low FET through GND.

To reduce the noise and improve the efficiency, please minimize these two loop area.

Especially input capacitor and output capacitor should be connected to GND (PGND) plain.

PCB Layout may affect the thermal performance, noise and efficiency greatly. So please take extra care when designing

PCB Layout patterns.

VIN

VOUT

COUT

CIN

FET

Figure 26. Current loop Buck regulator system

・The thermal Pad on the back side of IC has the great thermal conduction to the chip. So using the GND plain as broad and

wide as possible can help thermal dissipation. And a lot of thermal via for helping the spread of heat to the different layer is

also effective.

・The input capacitors should be connected to PGND as close as possible to the VIN terminal.

・The inductor and the output capacitors should be placed close to SW pin as much as possible.

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●List of Evaluation Board Components

VREG

PGOOD

100kΩ

4.7kΩ

1.5kΩ 13kΩ

GND

BOOT

GND

C6 VREG_C

0.022μF

VREG

TEST

BOOT_C

0.01μF

Thermal Pad

(Shorted to GND)

GND

VIN

12V

VOUT

3.3V

3.3µ H

COUT

CIN

10µ F

22µ F

PGND

Figure 27. Typical Application Circuit (VOUT=3.3V)

Table 1. Recommended BOM List(VIN=12V)

Symbol

Part

Coil

Value

Manufacture

TOKO

TDK

Series

FDVC0630 Series

SPM6530 Series

GRM31CR71E16KA12

GRM31CB31C226ME15

GRM18 Series

※

CIN (C1, C2)

Ceramic capacitor

Resistance

10F / 25V

22F / 16V

0.01F / 50V

100kΩ

Murata

Rohm

COUT (C3, C4)

BOOT_C (C5)

MCR03 Series

Resistance

※

Rohm

MCR03 Series

Resistance

※

Rohm

MCR03 Series

Resistance

※

Rohm

MCR03 Series

VREG_C (C6)

Ceramic capacitor

F / 50V

Murata

GRM18 Series

VOUT

※

1.0V

1.2V

1.8V

3.3V

5.0V

360Ω

2kΩ

5.6kΩ

13kΩ

24kΩ

130Ω

2.2kΩ

4.7kΩ

1.5H

2.2H

3.3H

220Ω

110Ω

1.5kΩ

680Ω

The above components list is an example. Please check actual circuit characteristics on the application carefully before use.

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●I/O Equivalence circuit

VIN

BOOT

VIN

BOOT

VIN

BOOT

VREG

PGOOD

VOUT

PGOOD

167k

833k

VREG

VIN

BOOT

VREG

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●Operational Notes

(1) Absolute Maximum Ratings

Use of the IC in excess of absolute maximum ratings may result in damage to the IC. Assumptions should not be made

regarding the state of the IC (e.g., short mode or open mode) when such damage is suffered. If operational values are

expected to exceed the maximum ratings for the device, consider adding protective circuitry (such as fuses) to eliminate

the risk of damaging the IC.

(2) GND voltage

The potential of the GND, PGND pin must be the minimum potential in the system in all operating conditions.

(3) Thermal design

Use a thermal design that allows for a sufficient margin for power dissipation (Pd) under actual operating conditions

(4) Inter-pin Shorts and Mounting Errors

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

poor soldering or foreign objects may result in damage to the IC.

(5) Operation in Strong Electromagnetic Fields

Using this product in strong electromagnetic fields may cause IC malfunction. Caution should be exercised in

applications where strong electromagnetic fields may be present.

(6) ASO (Area of Safe Operation)

When using the IC, ensure that operating conditions do not exceed absolute maximum ratings or ASO of the output

transistors.

(7) Testing on application boards

When testing the IC on an application board, connecting a capacitor directly to a low-impedance 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 a jig or fixture during the evaluation process. To prevent

damage from static discharge, ground the IC during assembly and use similar precautions during transport and storage.

(8) Electrical Characteristics

The electrical characteristics indicated in this datasheet may change upon the conditions of temperature, supply voltage,

and external components. Please validate/verify your design at the worst case conditions.

(9) Not of a radiation-resistant design.

(10) Back Electromotive Force

If a large inductive load is connected at the output pin that might cause introducing back electromotive force at the start

up and at the output disable, please insert protection diodes.

OUTPUT

Figure 28. Back Electromotive Force

(11) Regarding input pins of the IC

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

PN junctions are formed at the intersection of these P layers with the N layers of other elements, creating parasitic

diodes and/or transistors. For example (refer to the figure below):､

• When GND > Pin A and GND > Pin B, the PN junction operates as a parasitic diode

• When GND > Pin B, the PN junction operates as a parasitic transistor

Parasitic diodes occur inevitably in the structure of the IC, and the operation of these parasitic diodes can result in mutual

interference among circuits, operational faults, or physical damage. Accordingly, 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.

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Resistor

Transistor (NPN)

Pin B

Pin A

P⁺

P substrate

Parasitic

element

Parasitic

element

P substrate

GND

Other adjacent

elements

GND

Parasitic element

Figure 29. Example of IC structure

(12) Ground Wiring Pattern

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

connected to a single ground potential within the application in order to avoid variations in the small-signal ground

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

voltage.

(13) Operating Condition

The electrical characteristics indicated in this datasheet are not guaranteed for the whole operational and temperature

ranges, however these characteristics do not significantly fluctuate within the operational and temperature ranges.

(14) Thermal shutdown (TSD) circuit

The IC incorporates a built-in thermal shutdown circuit, which is designed to turn the IC off completely in the event of

thermal overload. It is not designed to protect the IC from damage or guarantee its operation. ICs should not be used

after this function has activated, or in applications where the operation of this circuit is assumed. If the thermal

shutdown is activated while the load current exists, the output may possibly be latched off at the release of the thermal

shutdown.

TSD ON Temp.[℃] (typ.)

Hysteresis Temp[℃] (typ.)

175

(15) Heat Sink (FIN)

The heat sink (FIN) is connected to the substrate. Please connect it to GND.

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●Thermal Derating Curves

(1) 4 layer board

(All layers with 5505 mm²copper heat dissipation pads)

θj-a=47.0℃/W

(2) 4 layer board

(6.28 mm²copper heat dissipation pad on top and bottom layer,

5505 mm²pad on 2^ndand 3^rdlayer)

θj-a=70.62℃/W

(3) 1 layer board (6.28 mm²copper heat dissipation pad)

θj-a=201.6℃/W

Figure 30. Thermal derating curve

(VQFN016V3030)

●Ordering Information

B D 9 5 8 4 1 M U V

E 2

Part Number

Package

MUV: VQFN016V3030

Packaging and forming specification

E2: Embossed tape and reel

●Physical Dimension Tape and Reel Information

VQFN016V3030

3.0 0.1

Tape

Embossed carrier tape

3000pcs

Quantity

Direction

of feed

1PIN MARK

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

(

)

0.08

1.4 0.1

C0.2

0.5

+0.05

−0.04

Direction of feed

1pin

0.25

0.75

Reel

(Unit : mm)

Order quantity needs to be multiple of the minimum quantity.

∗

●Marking Diagram

VQFN016V3030 (TOP VIEW)

Part Number Marking

D 9 5

8 4 1

LOT Number

1PIN MARK

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●Revision History

Date

Revision

001

Changes

New Release

6.Aug.2012

24.Aug.2012

18.Mar.2013

Revised the General Description

002

003

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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 (Pd) depending on Ambient temperature (Ta). When used in sealed area, confirm the actual

ambient 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-GE

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

QR code 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 our Products might fall under controlled goods prescribed by the applicable foreign exchange and foreign trade act,

please consult with ROHM representative 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. ROHM shall not be in any way responsible or liable

for infringement of any intellectual property rights or other damages arising from use of such information or data.:

2. 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 information contained in this document.

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-GE

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

BD95841MUV [ROHM]

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