MB3845PFV - Fujitsu Quantum Devices Limited

DS04-27604-2E

FUJITSU SEMICONDUCTOR

DATA SHEET

ASSP For Power Supply Applications

Power Management 2-ch Switch IC

MB3842/MB3845

■DESCRIPTION

The MB3842/3845 is a power management switch with built-in 2-channel low-on resistance (typ. 100mΩ) switch.

Output control is by means of a control signal, and the MB3842 is designed for high-active operation (output on

when EN is Hi), while the MB3845 is designed for low-active operation (output on when EN is low.)

To provide adaptability to a variety of operations, the MB3842/3845 features low input voltage (VIN > 2.5V)

operation and stable low-on resistance independent of input voltage. The switching current limit can be set from

100mA to 600mA by using external resistance, and when overcurrent conditions are detected the OC output goes

low to provide an external notification signal.

VIN is divided between the two channels, which operate independently of each other.

In addition, an off-state reverse current prevention function is provided to ensure accurate on/off switching action.

■FEATURES

• Low on resistance switch (typ. 100mΩ)

• Low input voltage operation (2.5 V to 5.5 V)

• Switch current (max. 0.6 A)

•UVLO :V

IN threshold 2.3V/2.1 V hysteresis 200 mV

• ENABLE :EN threshold EN 1.4V/1.6 V for MB3842, EN 1/2 VIN f or MB3845

:Power supply current at output off = 0µA EN < 0.8V for MB3842, EN = VIN for MB3845

• External setting for soft start time and switch current limit.

• Over-temperature detection (switch latched off), over-current detection (not latched)

• OC pin flag set following overcurrent detection, over-temperature detection, or UVLO detection.

• Reverse current prevention at OFF (VIN ≥ 1.5 V)

• Either channel may be operated alone.

■PACKAGE

20-pin plastic SSOP

(FPT-20P-M03)

MB3842/MB3845

■PIN ASSIGNMENT

GND

OC1

OUT1

OUT2

OC2

GND

EN1, EN1

SS1

CS1

VIN1

VIN2

CS2

SS2

EN2, EN2

SSOP-20P

(FPT-20P-M03)

EN Enable

CS Current Set OC Over Current

EN Enable SS Slow Start

The functions of pin 1 and pin 10 differ on the MB3842 and MB3845.

EN for MB3842/EN for MB3845

MB3842/MB3845

■PIN DESCRIPTION

Pin no. Symbol Descriptions

1/10

(MB3842)

Control signal input pin.

Set “H” to turn s witch on, “L” to turn toff. At 0.8 V or less , the chip is in STBY state

and current consumption is less than 1µA.

“L” level is 1.4V (typ), “H” level is 1.6V (typ), with 200mV (typ) hysteresis.

(MB3845)

Control signal input pin.

Set “L” to turn switch on, “H” to turn off.

At “H” level = VIN, the chip is in STBY state and current consumption is less than

1µA.

Normally used as CMOS inverter input, so that recommended use is “L” level at

GND +0.5V or less, and “H” level is VIN -0.5V or greater.

2/9 SS Slow start setting pin. Used to adjust the switch on/off timing.

Add external capacitance to delay operation. Leave open when not in use.

In open mode v oltages up to 12 V are present. Care should be taken in mounting

to prevent leakage current generation because high impedance is required.

3/8 CS Current limit setting pin.

The limit current level is set by connecting this pin to external resistance.

4/5/6/7 VIN

Switch output pin.

An UVLO (VIN power monitor function) is provided so that when VIN reaches 2.3V

(typ .) or higher the OC pin v oltage goes to “H” le vel. Also if the VIN v oltage drops to

2.1 V (typ.) or lower the OC output goes to “L” state.

200mV (typ) hysteresis is provided.

11/20 GND Ground pin.

12/19 OC

External notification pin.

When the switch is in on mode this pin normally outputs a “H” level signal, but

changes to “L” level when an o vercurrent, overtemperature, or UVLO condition is

detected.

This is an open drain connection, and should be pulled up to high potential using

resistance.

13/14/15

16/17/18 OUT Switching output pin.(N-ch MOSFET source)

MB3842/MB3845

■BLOCK DIAGRAM (for 1 channel)

SS1

EN1

VIN1

OSC1

BGR1

−

COMP

FF1

OC1

OUT1

CS1

−

COMP

MB3842

SS1

EN1

VIN1

OSC1

BGR1

−

COMP

FF1

OC1

OUT1

CS1

−

COMP

MB3845

Temperature

protection 1

Charge

pump1 Over current

detection 1

Charge

pump1 Over current

detection 1

Temperature

protection 1

MB3842/MB3845

■ABSOLUTE MAXIMUM RATINGS

WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current,

temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings.

■RECOMMENDED OPERATING CONDITIONS

* :For CSS, RLIM settings, see “TYPICAL CHARACTERISTICS” and “FUNCTIONAL DESCRIPTION”.

WARNING: The recommended operating conditions are required in order to ensure the normal operation of the

semiconductor device. All of the device's electrical characteristics are warranted when the device is

operated within these ranges.

Alwa ys use semiconductor de vices within their recommended oper ating condition ranges. Oper ation

outside these ranges may adversely affect reliability and could result in device failure.

No warr anty is made with respect to uses, operating conditions, or combinations not represented on

the data sheet. Users considering application outside the listed conditions are advised to contact their

FUJITSU representatives beforehand.

Parameter Symbol Condition Rating Unit

Max. Min.

Input voltage VIN — –0.3 7.0 V

ENABLE voltage VEN — –0.3 7.0 V

Switch current ISW ——1.8A

Power dissipation PDTa = +85°C — 216 mW

Storage temperature TSTG — –55 +125 °C

Parameter Symbol Condition Value Unit

Min. Typ. Max.

Input voltage VIN —2.55.05.5V

ENABLE voltage VEN VEN ≤ VIN 0—5.5V

Switch current ISW VIN = 2.5 V to 5.5 V — — 0.6 A

SS pin capacitance CSS* — — — 10 nF

OC sink current IOCS VIN = 5.0 V, VOC = 0.4 V 2.0 5.0 — mA

Current limit

resistance RLIM*VIN = 5.0 V (ISW = 0.6 A) 1.4 2.0 2.6 kΩ

VIN = 5.0 V (ISW = 0.1 A) 3.6 6.2 9.1 kΩ

Operating

temperature TOP — –20 — +85 °C

MB3842/MB3845

■ELECTRICAL CHARACTERISTICS (per 1 ch)

• MB3842/MB3845 (VIN = 5 V, Ta = +25°C)

• MB3842 (VIN = 5 V, Ta = +25°C)

• MB3845 (VIN = 5 V, Ta = +25°C)

Parameter Symbol Condition Value Unit

Min. Typ. Max.

Switch resistance RON ISW =0.6A — 100 150 mΩ

IN pin input current

IIN1 ISW = 0 A — 350 550 µA

IIN2 ISW = 0.6 A — 1.0 1.5 mA

IIN3 EN < 0.8V for MB3842,

EN = VIN for MB3845 ——1.0µA

UVLO threshold VIUH VIN at OC = L → H 2.1 2.3 2.5 V

VIUL VIN at OC = H → L 1.9 2.1 2.3 V

UVLO hysteresis width VIUHY VIUHY = VIUH – VIUL 100 200 300 mV

Switch current limit ISWH RLIM = 2.0 kΩ0.42 0.6 0.78 A

ISWL RLIM = 6.2 kΩ0.06 0.1 0.14 A

OC sink current IOCS VOC = 0.4 V at OC active 2.0 5.0 — mA

IOCL VOC = 5.0 V at OC non-active — — 1.0 µA

Temperature protection (Tj)T

LIM — +125 — — °C

OUT pin rise time tON SS pin: Open

OUT pin: 100 kΩ pull down — 100 200 µs

OUT pin fall time tOFF SS pin: Open

OUT pin: 100 kΩ pull down —50120µs

Parameter Symbol Condition Value Unit

Min. Typ. Max.

ENABLE pin input current IENH VEN = 5 V, ISW = 0 A — 5 10 µA

IENL VEN = 0 V, ISW = 0 A — 0.0 — µA

ENABLE pin threshold

voltage VTHEN — 1.45 1.60 1.75 V

VTLEN — 1.25 1.40 1.55 V

ENABLE hysteresis width VENHY VENHY = VTHEN – VTLEN 100 200 300 mV

Parameter Symbol Condition Value Unit

Min. Typ. Max.

ENABLE pin input current IENH VEN = 5 V, ISW = 0 A — 0.0 — µA

IENL VEN = 0 V, ISW = 0 A — 0.0 — µA

ENABLE pin input voltage VILEN —0—0.8V

VIHEN —3.0—5.0V

MB3842/MB3845

■DIAGRAM

(Continued)

VIN

VOUT

IOUT

SW OFF

Overcurrent does not occur

SW ON SW ON

5 V

Low

5 V

• Normal operation

SW ONSW ONSW ON

2.3 V

2.1 V

5 V

Low

5 V

= 0 V

VIN

OUT

Overcurrent does not occur

•At V

IN fall

Note: The OC pin should be pulled up using a separate power supply and resistance.

(This illustration shows pull-up with a separate 5V source.)

MB3842/MB3845

(Continued)

SW ON OFF ON OFF

VIN

VOUT

IOUT

5 V

Low

5 V

= 0 V

• At overcurrent detection

SW ON

Over-temperature corrected

Over-temperature

occurs

SW OFF

VIN

OUT

5 V

Low

5 V

= 0 V

Overcurrent does not

occur

Latch set Latch released

• At over-temperature occurrence

Note: The OC pin should be pulled up using a separate power supply and resistance.

(This illustration shows pull-up with a separate 5V source.)

MB3842/MB3845

■TYPICAL CHARACTERISTICS

(Continued)

VIN = 5.0 V

VIN = 3.3 V

VIN = 2.5 V

0.1

0.01100 1000 10000 100000

RLIM (Ω)

ISW(A)

•R

LIM vs. limit current characteristics

VIN = 5.0 V

VIN = 3.3 V

VIN = 2.5 V

100

0.1 10 100 1000 10000 100000

CSS (pF)

tON(ms)

•C

SS vs. TON (SS) characteristics

These are the limiting value characteristics for CS pin-to-GND

external resistance and output current (OC flag).

There are the characteristics for SS pin-to-GND external

capacitance and output ON time.

MB3842/MB3845

(Continued)

150

140

130

120

110

100

50−60 −40 −20 0 20 40 60 80 100 120

at 0.1 A

at 0.6 A

at 1 A

−40 °C

25 °C

100 °C

150

140

130

120

110

100

50 234567

• SW resistance vs. temperature characteristics

• Temperature-depended SW resistance vs. VIN (V) characteristics

SW resistance (mΩ)

Temperature Ta (°C)

SW resistance (mΩ)

VIN voltage (V)

MB3842/MB3845

(Continued)

5 V

100 kΩ

2 Ω

VIN

ISW

VSW

RLIM

GND

EN, EN OC

OUT

VIL/VIH

1600

1400

1200

1000

800

600

400

200

00234561

ISW (mA)

6.2 k (0.1 A)

2 k (0.6 A)

VSW (V)

Measurement circuit

These are the output saturation current characteristics in

overcurrent state.(when not controlled by the OC pin warning flag)

RLIM not limited (CS GND)

RLIM set to 2.0kΩ, 0.6A

Temperature protection

range

RLIM set to 6.2kΩ, 0.1A Overcurrent flag set

(when set for 0.1A)

Overcurrent flag set

(when set for 0.6A)

Unlimited

• Output power (ISW) saturation characteristics

“Open”

MB3842/MB3845

(Continued)

• Power derating characteristics

Power dissipation PD (W)

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

−20 0 20 40 60 80 100

1 V / 500 NS 50 kΩ

Temperature Ta (°C)

1 V / 500 NS 1 kΩ

GND

1 V / 500 NS 10 kΩ1 V / 500 NS 100 kΩ

• OC pin flag pull-up resistance (pull-up power 5V) dependant overcurrent operation

MB3842/MB3845

■FUNCTIONAL DESCRIPTION

Current Limit Setting

By placing resistance between the CS and GND pins, the current limit can be set between 100mA and 600mA

within ±30% accuracy (VIN = 5 V, current limit at 600mA). Because the setting value is dependent on VIN voltage,

the user should select the optimum resistance value for the value of VIN voltage . When the switching current

exceeds the set value, the OC pin goes to “L” level as an external notification signal, but there is no latching

function. To hold operation on “off” state, the input signal to the EN and EN pins should be used.

When a direct connection to GND is used, there is no current limitation.

When the connection is open, the switch is in a state of continuously held current limits.

Thermal Shutdown

The MB3842/MB3845 has a thermal shutdown function which turns the switch off and sets the latch to protect

the device when junction temperature exceeds 125°C.

At the same time the OC output signal goes to “L” level to notify external systems.

The latch function can be reset by sending a low signal to the EN input of the MB3842, or a high signal to the

EN input of the MB3845.

Slow Start

The on/off switching time can be delayed by applying capacitance between the SS and GND pins. Controlling

the on time can soften surge current to the load side capacitance when power is turned on.

For details, see “Css vs. tON (SS) characteristics” on p. 9.

UVLO

A VIN voltage monitoring function is provided, so that when VIN voltage exceeds 2.3 V (typ) the OC pin voltage

goes to “H” level. When VIN voltage falls below 2.1V (typ), the OC output goes to “L” state.

Error Flag OC Pin

The OC pin produces a “L” signal in case of a UVLO, overcurrent, or over-temperature condition. In case of

overcurrent, the output has a pulse waveform. See P12.

(note) Output current limit setting resistance values are shown on P9, and in the following table. (CS pin-to-GND)

Standard Values

VIN/ISW 0.1 A 0.2 A 0.3 A 0.4 A 0.5 A 0.6 A 0.7 A 0.8 A 0.9 A 1.0 A

VIN 5.0V 6.2 kΩ4.3 kΩ3.3 kΩ2.7 kΩ2.2 kΩ2.0 kΩ1.8 kΩ1.6 kΩ1.4 kΩ1.3 kΩ

VIN 3.3V 9.1 kΩ5.6 kΩ4.3 kΩ3.3 kΩ2.7 kΩ2.4 kΩ2.0 kΩ1.8 kΩ1.6 kΩ1.5 kΩ

VIN 2.5V 13 kΩ7.5 kΩ5.1 kΩ3.9 kΩ3.0 kΩ2.7 kΩ2.2 kΩ2.0 kΩ1.8 kΩ1.6 kΩ

MB3842/MB3845

■TYPICAL APPLICATION

CSS

RLIM

CSS

EN1

SS1

CS1

VIN1

VIN2

CS2

SS2

EN2

GND

OC1

OUT1

OUT2

OC2

GND

MB3842/MB3845 Top View

Control signal

Pull-up resistance

Load

Pull-up resistance

MB3842/MB3845

■APPLICATION EXAMPLE

(1) Dual-Port Self-Powered Hub Application (NON-GANG Mode Connection)

5 V

USB 5 V Controller

Overcurrent

ON/OFF

Power Supply

USB

Port 1

USB

Port 2

MB3842/MB3845

EN1,EN1

SS1

CS1

VIN1

VIN2

CS2

SS2

EN2,EN2

GND

OC1

OUT1

OUT2

OC2

GND

*The MB3842 can also be adapted for use with 3.3V controllers.

USB Port 500mA MAX Par Port

Smoothing capacitors should be placed between VIN and GND, or between OUT and GND as required.

MB3842/MB3845

(2) Dual-Port Bus Powered Hub Application (GANG Mode Connection)

USB

Overcurrent

ON/OFF

5 V

Upstream Port

MB3842/MB3845

USB Port1(×4)

USB Port2(×4)

400 mA MAX

(100 mA ×4)

400 mA MAX

(100 mA ×4)

EN1,EN1

SS1

CS1

VIN1

VIN2

CS2

SS2

EN2,EN2

GND

OC1

OUT1

OUT2

OC2

GND

USB Port 100mA MAX Par Port

Smoothing capacitors should be placed between VIN and GND, or between OUT and GND as required.

MB3842/MB3845

■USAGE PRECAUTION

1. Never use settings exceeding maximum rated conditions.

Exceeding maximum rated conditions may cause permanent damage to the LSI.

Also, it is recommended that recommended operating conditions be observed in normal use.

Exceeding recommended operating conditions may adversely affect LSI reliability.

2. Use this device within recommended operating conditions.

Recommended operating conditions are values within which normal LSI operation is warranted.

Standard electrical characteristics are warranted within the range of recommended operating conditions and

within the listed conditions for each parameter.

3. Printed circuit board ground lines should be set up with consideration for common

impedance.

4. Take appropriate static electricity measures.

• Containers f or semiconductor materials should ha ve anti-static protection or be made of conductive material.

• After mounting, printed circuit boards should be stored and shipped in conductive bags or containers.

• Work platforms, tools, and instruments should be properly grounded.

• Working personnel should be grounded with resistance of 250 kΩ to 1 MΩ between body and ground.

5. Do not apply negative voltages.

The use of negative voltages below –0.3 V may create parasitic transistors on LSI lines, which can cause

abnormal operation.

6. Reverse Current Prevention Function

Current cannot flow back to the VIN pin with the switch off, even when the OUT pin voltage is higher than the

VIN pin (OUT ≥ VIN), however when VIN pin voltage is lower than 1.5 V circuit functions are lost, so that in this

case there is danger of reverse current flow. For applications in which reverse flow is not acceptable, set

VIN ≥ 1.5 V.

■ORDERING INFORMATION

Part number Package Remarks

MB3842PFV

MB3845PFV

MB3845PFV-ER 20-pin Plastic SSOP

(FPT-20P-M03)

MB3842/MB3845

■PACKAGE DIMENSION

1994 FUJITSU LIMITED F20012S-2C-4

0.50±0.20

(.020±.008)

0.10±0.10(.004±.004)

(STAND OFF)

0 10°

Details of "A" part

5.85(.230)REF

6.50±0.10(.256±.004)

0.65±0.12

5.40(.213)4.40±0.10 6.40±0.20 NOM(.252±.008)(.173±.004)

(.0256±.0047) .006 –.001

+.002

–0.02

+0.05

0.15

.009 –.002

+.004

–0.05

+0.10

0.22

.049 –.004

+.008

–0.10

+0.20

1.25

0.10(.004)

"A"

INDEX

(Mounting height)

Dimensions in mm (inches).

20-pin plastic SSOP

(FPT-20P-M03) *: These dimensions do not include resin protrusion.

MB3842/MB3845

FUJITSU LIMITED

The contents of this document are subject to change without notice.

Customers are advised to consult with FUJITSU sales

representatives before ordering.

The information and circuit diagrams in this document are

presented as examples of semiconductor device applications, and

are not intended to be incorporated in devices for actual use. Also,

FUJITSU is unable to assume responsibility for infringement of

any patent rights or other rights of third parties arising from the use

of this information or circuit diagrams.

The products described in this document are designed, developed

and manufactured as contemplated for general use, including

without limitation, ordinary industrial use, general office use,

personal use, and household use, but are not designed, developed

and manufactured as contemplated (1) for use accompanying fatal

risks or dangers that, unless extremely high safety is secured, could

have a serious effect to the public, and could lead directly to death,

personal injury, severe physical damage or other loss (i.e., nuclear

reaction control in nuclear facility, aircraft flight control, air traffic

control, mass transport control, medical life support system, missile

launch control in weapon system), or (2) for use requiring

extremely high reliability (i.e., submersible repeater and artificial

satellite).

Please note that Fujitsu will not be liable against you and/or any

third party for any claims or damages arising in connection with

above-mentioned uses of the products.

Any semiconductor devices have an inherent chance of failure. You

must protect against injury, damage or loss from such failures by

incorporating safety design measures into your facility and

equipment such as redundancy, fire protection, and prevention of

over-current levels and other abnormal operating conditions.

If any products described in this document represent goods or

technologies subject to certain restrictions on export under the

Foreign Exchange and Foreign Trade Law of Japan, the prior

authorization by Japanese government will be required for export

of those products from Japan.

F0001

 FUJITSU LIMITED Printed in Japan