ROHM BD7700GU Technical data

System LED Drivers for Mobile Phones

Charge Pump type for Flash

BD7700GU

●Description

BD7700GU is a maximum of 300mA LED flash (three-channel total) driver IC. Flash mode and torch mode are controllable by two external control signals. The flash mode timer ability for a maximum of 1s is carried, and management of flash lighting time is easy and safe.

●Features

1) Current regulation for LED

2) 3ch High side current Driver

3) Flash LED High side Current driver (Max 100mA@1ch)

4) Torch LED High side Current driver (Max 20mA@1ch)

5) Indicate LED High side Current driver (Max 1mA)

6) High efficiency up to 80%

7) 2port control Flash and Torch and Indicate mode

8) Charge pump step-up DC/DC converter (Max 300mA) Three charge pump mode (×1, ×1.5, ×2.0)

9) Automatically transition to each mode

10) Over-voltage protection / In rush current prevention (soft start) / Over current limiter

11) Under Voltage Lockout threshold / Thermal shutdown

12) Small and thin CSP package

●Applications

Flash and torch of camera for mobile phone

●Absolute Maximum Ratings (Ta=25℃)

No.11041EAT19

Parameter Symbol Ratings Unit

Maximum applied voltage VMAX 7 V

Input voltage Vdin GND-0.3 ~ VBAT+0.3 V

Power dissipation Pd 1062.5 (Note1) mW

Operating temperature range Topr -30 ~ +85 ℃

Storage temperature range Tstg -55 ~ +150 ℃

(Note1) The measurement value, which was mounted on the PCB by ROHM. Temperature deleting : 8.5mW/℃ from Ta>25℃

●Operating conditions (Ta=-30 ~ 85℃)

Parameter Symbol Ratings Unit

Battery Power Supply voltage VBAT 2.7 - 5.5 V

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●Electrical Characteristics (Unless otherwise noted, Ta = 25℃, VBAT=3.6V)

Parameter Symbol

Logic control terminal

Low threshold voltage VthL2 - - 0.4 V CNT0 and CNT1 port

High threshold voltage VthH2 1.2 - - V CNT0 and CNT1 port

High level Input current IinH2 - 18.3 33 μA CNT0 or CNT1 = 5.5V

Low level Input current IinL2 -1 0 - μA CNT0 or CNT1 = 0V

DC/DC Converter

Quiescent Current Iq - 0.1 1.0 μA CNT0 and CNT1 = ‘0’

Flash Current Accuracy Iflash -15 0 15 % 100mA

Torch Current Accuracy Itorch -15 0 15 % 20mA

Indicate Current Accuracy Iind -30 0 30 % 1mA,LED2 Terminal

Min. Typ. Max.

Limits

Units Condition

Technical Note

Current Consumption 1 Idd1 - 1.0 2.0 mA X1.0 mode, LED current = 0mA

Current Consumption 2 Idd2 - 6.0 9.0 mA X1.5 mode, LED current = 0mA

Current Consumption 3 Idd3 - 9.0 12.0 mA X2.0 mode, LED current = 0mA

ISET Voltage Viset 0.5 0.6 0.7 V

Switching frequency Fsw 1.0 1.25 1.5 MHz

Sat Voltage Vsat 150 250 350 mV VOUT-LED Voltage(VLED=3V)

Over voltage protection Vovp 5.5 - - V VOUT Limit

Under voltage lock-out Vuvlo 1.8 2.0 2.2 V UVLO Detect Voltage

Start up time Tstart - - 3 ms Stand by → Torch,Flash,Indicate

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●Package Outline

Technical Note

Fig.1. Package outline

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Fig.1. Package outline

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●Block Diagram

Technical Note

C1 C2

C1N C1P C2N C2P

VBAT

CIN

CNT0

CNT1

●Pin Location

CHPREG

DIGTOP

CHP_TOP

OSC

REF_DP

VOUTDET

GND

C1, C2, CIN : 2.2µF COUT :4.7µF

Fig-2. Block Diagram

Bottom View

LEDDRVTOP

LEDDRV

ISETDRV

VOUT

COUT

LED1

LED2(Indicate out)

LED3

ISET

RSET

D C1N C2N C2P C1P

C GND CNT0 CNT1 VBAT

BISET LED3 VOUT

A GND VBAT LED2 LED1

1234

Fig-3. Pin Location

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●Terminals

ESD Diode

for Power for GND

VBAT

PAD

GND

Type-E

VBAT

PAD

GND

Functions

Type-C

VBAT

PAD

GND

Type-F

VBAT

PAD

GND

VBAT

GND

In/

Out

VOUT

Type

Type-B

No. Pin Name

C4 VBAT - A - GND Battery power supply pin

A2 VBAT - A - GND Battery power supply pin

C2 CNT0 In G VBAT GND LED control input ‘1’: On, ‘0’: Off

C3 CNT1 In G VBAT GND LED control input ‘1’: On, ‘0’: Off

B4 VOUT Out A - GND Output Voltage

A4 LED1 Out D - GND Current drive out for Torch,Flash

A3 LED2 Out D - GND Current drive out for Torch,Flash,Indicate

B3 LED3 Out D - GND Current drive out for Torch,Flash

B1 ISET In B VBAT GND Resistor connection for LED current setting

D4 C1P In/Out B VBAT GND Positive terminal of transfer capacitor 1

D1 C1N In/Out A - GND Negative terminal of transfer capacitor 1

D3 C2P In/Out B VBAT GND Positive terminal of transfer capacitor 2

D2 C2N In/Out A - GND Negative terminal of transfer capacitor 2

C1 GND - F VBAT - Ground pin

A1 GND - F VBAT - Ground pin

Total : 15 Pin

Type-A

PAD

Type-D

PAD

GND

Type-G

PAD

Technical Note

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●Functional Description

1. “FLASH” and “TORCH” and “Indicate” pin control

“FLASH” and “TORCH” select

“FLASH” and “TORCH” is selected by “CNT0” and “CNT1” pin. Status is as bellows.

CNT1 CNT0 Status

0 0 All LED OFF

0 1 Indicate

1 0 TORCH

1 1 FLASH

“FLASH” control

“FLASH” status turns “High”, Flash LED Current is occurred, and “FLASH” status turns “Low”, Flash LED Current is OFF. “FLASH” status is set by CNT0 pin = “1” and CNT1 pin = “1”. Flash term is maximum 1s by internal timer.

CNT1

CNT0

CNT1

CNT0

ILED (0mA)

Fig-4. FLASH control and LED Current

LED

I (0mA)

Fig-5. FLASH control and LED Current (with Timer Limit)

Technical Note

300mA

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“TORCH” control

“TORCH” status turns “High”, LED Current is occurred at 60mA(Torch Mode, 3 channel total), and “TORCH” status turns “Low”, LED Current is OFF. “TORCH” status is set by CNT0 pin = “0” and CNT1 pin = “1”.

CNT1

CNT0

“Indicate” control

“Indicate” status turns “High”, LED2 Current is occurred at １ mA.LED1 and LED3 Current is occurred at 0mA.Indicate” status turns “Low”, LED Current is OFF. “Indicate” status is set by CNT0 pin = “1” and CNT1 pin = “0”.

2. LED Current control by “Rset”

The setting of Rset controls LED current, and following equation shows the LED current(@1ch).

Then, follows Table shows the LED current(@1ch) for some Rset settings.(Typical)

ILED (0mA)

CNT1

CNT0

LED1

(0mA)

Rset 120kΩ 62kΩ 30kΩ 20kΩ 15kΩ 12kΩ

Technical Note

60mA

Fig-6. TORCH control and LED Current

1mA

Fig-7. Indicate LED control and Indicate LED Current

ILED = 1200 / Rset (Flash)

ILED = 240 / Rset (Torch)

ILED = 12 / Rset (Indicate)

ILED(FLASH) 10mA 20mA 40mA 60mA 80mA 100mA

ILED(TORCH) 2mA 4mA 8mA 12mA 16mA 20mA

ILED(Indicate) 0.1mA 0.2mA 0.4mA 0.6mA 0.8mA 1mA

Ratio of Flash and Torch current deviates from 5:1 by RSET value in light-load of LED current.

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3. Charge pump mode transition

The charge pump mode is automatically and optimally changed.

(From x1 mode to x1.5 mode) (From x1.5 mode to x2.0 mode)

Power supply voltage goes down and this IC can’t keep constant LED current, then the mode transition will start.

(From x1.5 mode to x1 mode) (From x2.0 mode to x1.5 mode)

Power supply voltage goes up and the detection of VOUT and VBAT is worked, then the mode transition will start.

4. Over voltage and current protection

This IC has VOUT over voltage and current protection for VOUT. Even if LED pins are open, VOUT voltage is kept below limit voltage. Even if VOUT pin is short to GND, current limiter works and restrains VBAT current.

5. UVLO function

This IC is shut down when VBAT is under Vuvlo voltage. This IC automatically return initial operation when VBAT is up to Vuvlo voltage, and IC will return to normal operation.

6. Thermal shutdown function

This IC has a thermal shut down function. It works above 175℃, and under the situation, IC will change the status from active to inactive. To become under 175℃, IC will return to normal operation.

Technical Note

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●Selection of external parts Recommended external parts are as shown below. When to use other parts than these, select the following equivalent parts.

・Capacitor

Val ue Manufacturer Product number

Vertical

【 CIN 】

2.2µF MURATA GRM155B30J225ME 1.0 0.5 0.5 B 6.3V

【 COUT 】

4.7µF MURATA GRM188B31A475KE15D 1.6 0.8 0.8 B 10V

【 C1, C2 】

2.2µF MURATA GRM155B30J225ME 1.0 0.5 0.5 B 6.3V

[LED specification]

This IC targets to drive high power LED. Available V

F(Forward voltage) range of LED is as follows.

Typ Max

VF 3.4V 5V

at 100mA/1ch , Ta=25℃

Note) LED V

F range has Temperature characteristics. It is necessary tochoice suitable LED characteristics at LED

Current setting.

Available LED terminal Voltage range is changed by LED current.

LED Current vs LED Terminal Voltage

5.5

4.5

Max LED Voltage[V]

3.5

0 100 200

LED Current [mA]

Ron(x2.0)=1.76Ω

Size

Horizontal

size

Limit by OVP-0.3V

size

Height

Technical Note

Te mp .

Chara.

Rated

Voltage

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●Notes for use (1) Absolute Maximum Ratings

An excess in the absolute maximum ratings, such as supply voltage, temperature range of operating conditions, etc., can break down devices, thus making impossible to identify breaking mode such as a short circuit or an open circuit. If any special mode exceeding the absolute maximum ratings is assumed, consideration should be given to take physical safety measures including the use of fuses, etc.

(2) Operating conditions

These conditions represent a range within which characteristics can be provided approximately as expected. The electrical characteristics are guaranteed under the conditions of each parameter.

(3) Reverse connection of power supply connector

The reverse connection of power supply connector can break down ICs. Take protective measures against the breakdown due to the reverse connection, such as mounting an external diode between the power supply and the IC’s power supply terminal.

(4) Power supply line

Design PCB pattern to provide low impedance for the wiring between the power supply and the GND lines. In this regard, for the digital block power supply and the analog block power supply, even though these power supplies has the same level of potential, separate the power supply pattern for the digital block from that for the analog block, thus suppressing the diffraction of digital noises to the analog block power supply resulting from impedance common to the wiring patterns. For the GND line, give consideration to design the patterns in a similar manner. Furthermore, for all power supply terminals to ICs, mount a capacitor between the power supply and the GND terminal. At the same time, in order to use an electrolytic capacitor, thoroughly check to be sure the characteristics of the capacitor to be used present no problem including the occurrence of capacity dropout at a low temperature, thus determining the constant.

(5) GND voltage

Make setting of the potential of the GND terminal so that it will be maintained at the minimum in any operating state. Furthermore, check to be sure no terminals are at a potential lower than the GND voltage including an actual electric transient.

(6) Short circuit between terminals and erroneous mounting

In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting can break down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or between the terminal and the power supply or the GND terminal, the ICs can break down.

(7) Operation in strong electromagnetic field

Be noted that using ICs in the strong electromagnetic field can malfunction them.

(8) Inspection with set PCB

On the inspection with the set PCB, if a capacitor is connected to a low-impedance IC terminal, the IC can suffer stress. Therefore, be sure to discharge from the set PCB by each process. Furthermore, in order to mount or dismount the set PCB to/from the jig for the inspection process, be sure to turn OFF the power supply and then mount the set PCB to the jig. After the completion of the inspection, be sure to turn OFF the power supply and then dismount it from the jig. In addition, for protection against static electricity, establish a ground for the assembly process and pay thorough attention to the transportation and the storage of the set PCB.

(9) Input terminals

In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the parasitic element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of the input terminal. Therefore, pay thorough attention not to handle the input terminals, such as to apply to the input terminals a voltage lower than the GND respectively, so that any parasitic element will operate. Furthermore, do not apply a voltage to the input terminals when no power supply voltage is applied to the IC. In addition, even if the power supply voltage is applied, apply to the input terminals a voltage lower than the power supply voltage or within the guaranteed value of electrical characteristics.

Ground wiring pattern

(10)

If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of the small-signal GND. Pay attention not tocause fluctuations in the GND wiring pattern of external parts as well.

(11) External capacitor

In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to a degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc.

Technical Note

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(12) Not connecting input terminals

In terms of extremely high impedance of CMOS gate, to open the input terminals causes unstable state. Unstable state occurs from the inside gate voltage of p-channel or n-channel transistor into active. As a result, power supply current may increase. And unstable state can also cause unexpected operation of IC. So unless otherwise specified, input terminals not being used should be connected to the power supply or GND line.

(13) Thermal shutdown circuit (TSD)

When junction temperatures become setting temperature or higher, the thermal shutdown circuit operates and turns a switch OFF. The thermal shutdown circuit, which is aimed at isolating the LSI from thermal runaway as much as possible, is not aimed at the protection or guarantee of the LSI. Therefore, do not continuously use the LSI with this circuit operating or use the LSI assuming its operation.

(14) Thermal design

Perform thermal design in which there are adequate margins by taking into account the permissible dissipation (Pd) in actual states of use.

Technical Note

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●Ordering part number

B D 7 7 0 0 G U - E 2

Part No. Part No.

VCSP85H2

(BD7700GU)

1PIN MARK

15-φ0.3±0.05

0.05

(φ0.15)INDEX POST

0.37±0.1

D C B A

2.24±0.1

P=0.5×3

7700

0.08 S A

2.24±0.1

1.0MAX

0.25±0.1

0.37±0.1

P=0.5×3

(Unit : mm)

Package

GU : VCSP85H2

Embossed carrier tapeTape

Quantity

Direction of feed

3000pcs E2

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

Reel

1pin

Packaging and forming specification E2: Embossed tape and reel

Direction of feed

Order quantity needs to be multiple of the minimum quantity.

∗

Technical Note

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Notes

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Examples of application circuits, circuit constants and any other information contained herein illustrate the standard usage and operations of the Products. The peripheral conditions must be taken into account when designing circuits for mass production.

Great care was taken in ensuring the accuracy of the information specied in this document. However, should you incur any damage arising from any inaccuracy or misprint of such information, ROHM shall bear no responsibility for such damage.

The technical information specied herein is intended only to show the typical functions of and examples of application circuits for the Products. ROHM does not grant you, explicitly or implicitly, any license to use or exercise intellectual property or other rights held by ROHM and other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the use of such technical information.

The Products specied in this document are intended to be used with general-use electronic equipment or devices (such as audio visual equipment, ofce-automation equipment, communication devices, electronic appliances and amusement devices).

The Products specied in this document are not designed to be radiation tolerant.

While ROHM always makes efforts to enhance the quality and reliability of its Products, a Product may fail or malfunction for a variety of reasons.

Please be sure to implement in your equipment using the Products safety measures to guard against the possibility of physical injury, re or any other damage caused in the event of the failure of any Product, such as derating, redundancy, re control and fail-safe designs. ROHM shall bear no responsibility whatsoever for your use of any Product outside of the prescribed scope or not in accordance with the instruction manual.

The Products are not designed or manufactured to be used with any equipment, device or system which requires an extremely high level of reliability the failure or malfunction of which may result in a direct threat to human life or create a risk of human injur y (such as a medical instrument, transportation equipment, aerospace machiner y, nuclear-reactor controller, fuelcontroller or other safety device). ROHM shall bear no responsibility in any way for use of any of the Products for the above special purposes. If a Product is intended to be used for any such special purpose, please contact a ROHM sales representative before purchasing.

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ROHM BD7700GU Technical data

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