ROHM BD2802GU

System LED Drivers for Mobile phones
6LEDs
Illumination
BD2802GU
No.11041EAT12
●Description
The BD2802GU is a RGB LED driver specifically engineered for decoration purposes.This RGB driver incorporates lighting
patterns and illuminates without imposing any load on CPU.This RGB driver is best-suited for illumination using RGB LEDs
and decoration using monochrome LEDs.In addition, this RGB driver has been successfully miniaturized through the use of
a VCSP85H2 (2.8 mm 0.5 mm pitch) chip size package.
●Features
1) RGB LED driver (dual drivers)
- A slope control function is incorporated (allowing dual drivers to be controlled independently).
- Slope control can be implemented using the DC current.
- Two modes “continuous illumination mode” and “illumination single cycle mode” are supported.
- Independent external ON/OFF synchronizing terminals (of dual drivers) are provided.
2
- Multiple drivers can be used concurrently by using the I C address change function and supporting reference clock I/O.
2) Thermal shutdown
3) I2C BUS fast mode support (maximum rate: 400 kHz)
- A device address can be changed via an external pin.
*
*
*
This driver has not been designed for anti-radiation.
This document may be altered without prior notice.
This document does not provide for delivery.
●Absolute Maximum Ratings(Ta=25℃)
Parameter
Maximum Applied voltage
Power Dissipation
Operating Temperature Range
Storage Temperature Range
Symbol
Limits
Unit
VMAX
7
V
Pd
1250 (Note1)
mW
Topr
-40 ～ +85
℃
Tstg
-55 ～ +150
℃
o
o
(Note1)Power dissipation deleting is 10.0mW/ C, when it’s used in over 25 C.
(It’s deleting is on the board that is ROHM’s standard)
●Recommended Operating Conditions(VBAT≧VIO, Ta=-40～85℃)
Parameter
VBAT input voltage
VIO pin voltage
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© 2011 ROHM Co., Ltd. All rights reserved.
Symbol
Limits
Unit
VBAT
2.7 ～ 5.5
V
VIO
1.65 ～ 3.3
V
1/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Electrical Characteristics(Unless otherwise specified, Ta=25℃, VBAT=3.6V, VIO=1.8V)
Limits
Parameter
Symbol
Unit
Min.
Typ.
Max.
Condition
【Circuit Current】
VBAT Circuit current 1
IBAT1
-
0.1
3.0
μA
RESETB=0V, VIO =0V
VBAT Circuit current 2
IBAT2
-
0.5
3.0
μA
RESETB=0V, VIO=1.8V
VBAT Circuit current 3
IBAT3
-
0.8
1.2
mA
LED 6Ch ON, ILED=10mA setting
Exclusive of LED current,
RGBISET =120kΩ
step
RGB1 group, RGB2 group
【LED Driver】
LED current Step
ILEDSTP
128
LED Maximum setup
curren
IMAX
-
-
30.48
mA
LED current accurate
ILED
18
20
22
mA
LED current Matching
ILEDMT
-
5
10
%
LED OFF Leak current
ILKL
-
-
1.0
μA
fosc
0.8
1.0
1.2
MHz
RGB1 group, RGB2 group
RGBISET=100kΩ
RGB1 group, RGB2 group,
Terminal voltage =1V
ILED=20mA setting, RGBISET
=120kΩ
RGB1 group, between RGB2 group,
Terminal voltage =1V
ILED=20mA setting
【OSC】
OSC oscillation frequency
【SDA, SCL】(I2C interface )
L level input voltage
VILI
-0.3
-
0.25×VIO
V
H level input voltage
VIHI
0.75×VIO
-
VBAT+0.3
V
Hysteresis of Schmitt
trigger input
VhysI
0.05×VIO
-
-
V
L level output voltage
VOLI
0
-
0.3
V
SDA pin, IOL=3 mA
linI
-10
-
10
μA
Input voltage = 0.1×VIO～0.9×VIO
L level input voltage
VILR
-0.3
-
0.25×VIO
V
H level input voltage
VIHR
0.75×VIO
-
VBAT+0.3
V
Input current
IinR
-10
-
10
μA
-0.3
Input current
【RESETB】(CMOS input pin)
Input voltage = 0.1×VIO～0.9×VIO
【ADDSEL】(CMOS input pin)
L level input voltage
VILADD
-
0.25×VBAT
V
H level input voltage
VIHADD 0.7 ×VBAT
-
VBAT+0.3
V
Input current
IinADD
-
10
μA
-10
Input voltage = 0.1×VBAT～0.9×VBAT
【RGB1CNT, RGB2CNT】(CMOS input pin with Pull-down resistance)
L level input voltage
VILCNT
-0.3
H level input voltage
VIHCNT
IinCNT
Input current
-
0.25×VIO
V
0.75×VIO
-
VBAT+0.3
V
-
3.6
10
μA
Input voltage = 1.8V
【CLKIO(Output)】(CMOS output pin)
L level output voltage
VOLCLK
-
-
0.2
V
IOL=1mA
H level output voltage
VOHCLK
VIO-0.2
-
-
V
IOH=1mA
fclk
200
250
300
kHz
-
0.25×VIO
V
Output frequency
【CLKIO (Input)】(CMOS input pin)
L level input voltage
VILCLK
-0.3
H level input voltage
VIHCLK
0.75×VIO
-
VIO+0.3
V
Input current
IinCLK
-
3.6
10
μA
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© 2011 ROHM Co., Ltd. All rights reserved.
2/27
Input voltage = 1.8V
2011.04 - Rev.A
BD2802GU
Technical Note
●Block Diagram / Application Circuit example
VBAT
VBAT2
VREF
VBAT1
VBAT
1µF/10V
R1LED
VIO
1µF/10V
RESETB
Slope
Control
G1LED
(RGB1)
B1LED
RGB1
R2LED
SCL
SDA
2
Level
I C interface
Shift
Digital Control
I/O
Slope
Control
G2LED
(RGB2)
B2LED
RGB2
RGB1CNT
RGBGND
RGB2CNT
CLKIO
ADDSEL
CLKIO
T4
GND2
TSD
T3
T2
T1
IREF
GND1
RGBISET
Fig.3 Block Diagram / Application Circuit example
●Pin Arrangement ［Bottom View］
E
T4
D
B2LED
C
VBAT2
B
GND1
A
T1
1
G2LED RGBGND
R2LED
B1LED
G1LED
T3
R1LED
VBAT1
RGBISE RGB1CNT ADDSEL
GND2
index
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© 2011 ROHM Co., Ltd. All rights reserved.
CLKIO
SCL
SDA
RGB2CNT
VIO
RESETB
T2
2
3
4
5
3/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Outside size figure
VCSP85H2 CSP small Package
Size : 2.8mm×2.8mm (Tolerance : ± 0.1mm each side) height 1.0mm max
Ball pitch : 0.5 mm
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© 2011 ROHM Co., Ltd. All rights reserved.
4/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Pin Functions
Input Level
For Power For GND
No
Pin No.
Pin Name
I/O
ESD Diode
Functions
1
D5
VBAT1
-
-
GND
Battery is connected
A
2
C1
VBAT2
-
-
GND
Battery is connected
A
3
A1
T1
-
VBAT
GND
Test Pin (short to GND)
S
4
A5
T2
-
VBAT
GND
Test Pin (short to GND)
S
5
E5
T3
-
VBAT
GND
Test Pin (short to GND)
S
6
E1
T4
-
VBAT
-
Test Pin (short to GND)
B
7
A3
VIO
-
VBAT
GND
I/O voltage source is connected
C
8
A4
RESETB
I
VBAT
GND
Reset input (L: RESET, H: RESET cancel)
H
9
B5
SDA
I/O
VBAT
GND
I2C data input
I
10
B4
SCL
I
VBAT
GND
I2C clock input
H
11
B1
GND1
-
VBAT
-
Ground
B
12
C5
GND2
-
VBAT
-
Ground
B
13
E3
RGBGND
-
VBAT
-
Ground
B
14
C2
RGBISET
I
VBAT
GND
RGB LED reference current
O
15
D4
R1LED
I
-
GND
Red LED1 connected
E
16
E4
G1LED
I
-
GND
Green LED1 connected
E
17
D3
B1LED
I
-
GND
Blue LED1 connected
E
18
D2
R2LED
I
-
GND
Red LED2 connected
E
19
E2
G2LED
I
-
GND
Green LED2 connected
E
20
D1
B2LED
I
-
GND
Blue LED2 connected
E
21
C3
RGB1CNT
I
VBAT
GND
RGB1 LED external ON/OFF Synchronism
(L：OFF, H：ON)*
J
22
A2
RGB2CNT
I
VBAT
GND
RGB2 LED external ON/OFF Synchronism
(L：OFF, H：ON)*
J
23
C4
ADDSEL
I
VBAT
GND
I2C device address change terminal
R
24
B3
CLKIO
I/O
VBAT
GND
Standard clock input-and-output terminal
V
* A setup of a register is separately necessary to validate it.
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© 2011 ROHM Co., Ltd. All rights reserved.
5/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Equivalent circuit diagram
A
B
VBAT
G
C
VBAT
E
VIO
I
VBAT
VBAT
O
VBAT
U
F
VBAT
J
VBAT
VIO
L
VBAT
VBAT
N
Q
VBAT
VBAT
R
VBAT
VBAT
S
VBAT
VBAT
V
VBAT
X
VBAT
VBAT
VIO
H
VIO
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© 2011 ROHM Co., Ltd. All rights reserved.
VBAT
6/27
VIO
VBAT
2011.04 - Rev.A
BD2802GU
Technical Note
●I2C BUS format
The writing operation is based on the I2C slave standard.
・Slave address
A7
A6
A5
A4
A3
A2
A1
R/W
ADDSEL=L
0
0
1
1
0
1
0
0
ADDSEL=H
0
0
1
1
0
1
1
0
Slave address can be changed with the external terminal ADDSEL.
・Bit Transfer
SCL transfers 1-bit data during H. SCL cannot change signal of SDA during H at the time of bit transfer. If SDA changes
while SCL is H, START conditions or STOP conditions will occur and it will be interpreted as a control signal.
SDA
SCL
SDA a state of stability：
SDA
It can change
Data are effective
・START and STOP condition
When SDA and SCL are H, data is not transferred on the I2C- bus. This condition indicates, if SDA changes from H to L
while SCL has been H, it will become START (S) conditions, and an access start, if SDA changes from L to H while SCL
has been H, it will become STOP (P) conditions and an access end.
SDA
SCL
S
P
STOP condition
START condition
・Acknowledge
It transfers data 8 bits each after the occurrence of START condition. A transmitter opens SDA after transfer 8bits data, and
a receiver returns the acknowledge signal by setting SDA to L.
DATA OUTPUT
BY TRANSMITTER
not acknowledge
DATA OUTPUT
BY RECEIVER
acknowledge
SCL
S
1
2
9
clock pulse for
acknowledgement
START condition
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© 2011 ROHM Co., Ltd. All rights reserved.
8
7/27
2011.04 - Rev.A
BD2802GU
Technical Note
・Writing protocol
A register address is transferred by the next 1 byte that transferred the slave address and the write-in command. The 3rd
byte writes data in the internal register written in by the 2nd byte, and after 4th byte or, the increment of register address is
carried out automatically. However, when a register address turns into the last address, it is set to 00h by the next
transmission. After the transmission end, the increment of the address is carried out.
*1
S X X X X X X X 0 A A7 A6 A5 A4 A3 A2 A1 A0 A D7 D6 D5 D4 D3 D2 D1 D0 A
slave address
register address
*1
D7 D6 D5 D4 D3 D2 D1 D0 A P
DATA
DATA
register address
increment
R/W=0(write)
register address
increment
A=acknowledge(SDA LOW)
A=not acknowledge(SDA HIGH)
S=START condition
P=STOP condition
*1: Write Timing
from master to slave
from slave to master
●Timing diagram
SDA
t BUF
t SU;DAT
t LOW
t HD;STA
SCL
t HD;STA
S
t SU;STO
t SU;STA
t HD;DAT
Sr
t HIGH
P
●Electrical Characteristics(Unless otherwise specified, Ta=25 oC, VBAT=3.6V, VIO=1.8V)
Standard-mode
Parameter
Symbol
Min.
Typ.
Max.
Min.
【I2C BUS format】
SCL clock frequency
fSCL
0
100
0
LOW period of the SCL clock
tLOW
4.7
1.3
HIGH period of the SCL clock
tHIGH
4.0
0.6
Hold time (repeated) START condition
After this period, the first clock is generated
Set-up time for a repeated START
condition
Data hold time
Data set-up time
Set-up time for STOP condition
Bus free time between a STOP
and START condition
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© 2011 ROHM Co., Ltd. All rights reserved.
S
Fast-mode
Typ.
Max.
-
400
-
kHz
μs
μs
Unit
tHD;STA
4.0
-
-
0.6
-
-
μs
tSU;STA
4.7
-
-
0.6
-
-
μs
tHD;DAT
tSU;DAT
tSU;STO
0
250
4.0
-
3.45
-
0
100
0.6
-
0.9
-
μs
ns
μs
tBUF
4.7
-
-
1.3
-
-
μs
8/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Register map
Address
W/R
00h
Resister data
Function
D7
D6
D5
D4
D3
D2
D1
D0
W
-
-
CLKMD
CLKEN
-
-
-
SFTRST
Soft Reset clock setup
01h
W
-
RGB2MEL
RGB2OS
RGB2EN
-
RGB1MEL
RGB1OS
RGB1EN
RBG-LED control
02h
W
-
TRGB1(2)
TRGB1(1)
TRGB1(0)
RGB1-hour setup
03h
W
-
IR11(6)
IR11(5)
IR11(4)
IR11(3)
IR11(2)
IR11(1)
IR11(0)
R1 current 1 setup
04h
W
-
IR12(6)
IR12(5)
IR12(4)
IR12(3)
IR12(2)
IR12(1)
IR12(0)
R1 current 2 setup
05h
W
-
-
-
-
PR1(3)
PR1(2)
PR1(1)
PR1(0)
R1 Wave patturn setup
06h
W
-
IG11(6)
IG11(5)
IG11(4)
IG11(3)
IG11(2)
IG11(1)
IG11(0)
G1 current 1 setup
07h
W
-
IG12(6)
IG12(5)
IG12(4)
IG12(3)
IG12(2)
IG12(1)
IG12(0)
G1 current 2 setup
08h
W
-
-
-
-
PG1(3)
PG1(2)
PG1(1)
PG1(0)
G1 Wave patturn setup
09h
W
-
IB11(6)
IB11(5)
IB11(4)
IB11(3)
IB11(2)
IB11(1)
IB11(0)
B1 current 1 setup
0Ah
W
-
IB12(6)
IB12(5)
IB12(4)
IB12(3)
IB12(2)
IB12(1)
IB12(0)
B1 current 2 setup
0Bh
W
-
-
-
-
PB1(3)
PB1(2)
PB1(1)
PB1(0)
B1 Wave patturn setup
0Ch
W
-
TRGB2(2)
TRGB2(1)
TRGB2(0)
RGB2-hour setup
0Dh
W
-
IR21(6)
IR21(5)
IR21(4)
IR21(3)
IR21(2)
IR21(1)
IR21(0)
R2 current 1 setup
0Eh
W
-
IR22(6)
IR22(5)
IR22(4)
IR22(3)
IR22(2)
IR22(1)
IR22(0)
R2 current 2 setup
0Fh
W
-
-
-
-
PR2(3)
PR2(2)
PR2(1)
PR2(0)
R2 Wave patturn
10h
W
-
IG21(6)
IG21(5)
IG21(4)
IG21(3)
IG21(2)
IG21(1)
IG21(0)
G2 current 1 setup
11h
W
-
IG22(6)
IG22(5)
IG22(4)
IG22(3)
IG22(2)
IG22(1)
IG22(0)
G2 current 2 setup
12h
W
-
-
-
-
PG2(3)
PG2(2)
PG2(1)
PG2(0)
G2 Wave patturn setup
13h
W
-
IB21(6)
IB21(5)
IB21(4)
IB21(3)
IB21(2)
IB21(1)
IB21(0)
B2 current 1 setup
14h
W
-
IB22(6)
IB22(5)
IB22(4)
IB22(3)
IB22(2)
IB22(1)
IB22(0)
B2 current 2 setup
15h
W
-
-
-
-
PB2(3)
PB2(2)
PB2(1)
PB2(0)
B2 Wave patturn setup
SFRGB1(1) SFRGB1(0) SRRGB1(1) SRRGB1(0)
SFRGB2(1) SFRGB2(0) SRRGB2(1) SRRGB2(0)
Input "0” for "-".
Vacancy address may be use for test.
Prohibit to accessing the address that isn’t mentioned and the register for test.
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© 2011 ROHM Co., Ltd. All rights reserved.
9/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Register Description
Adress 00h <Soft Reset>
BIT
Name
Initial
D7
D6
D5
D4
D3
D2
D1
D0
CLKMD
CLKEN
SFTRST
0
0
0
Adress 01h
1
Clock Output mode
Clock input and output Effective
Reset
<RGB LED control >
BIT
Name
Init
D7
D6
D5
D4
D3
D2
D1
D0
RGB2MEL
RGB2OS
RGB2EN
RGB1MEL
RGB1OS
RGB1EN
0
0
0
0
0
0
*
*
Function
0
Clock Input mode
Clock input and output invalid
Reset Release
Function
0
RGB2 external control invalid
RGB2 Stop
RGB2 Stop
RGB1 external control invalid
RGB1 Stop
RGB1 Stop
1
RGB2 external control valid
RGB2 1 periodic operation
RGB2 continuous operation
RGB1 external control valid
RGB1 1 periodic operation
RGB1 continuous operation
RGB*OS returns to 0 automatically after 1 cycle operation.
RGB*EN precedes to RGB*OS. In use in 1 cycle operation, there is the necessity for RGB*EN=0.
Adress 02h
<RGB1 time>
BIT
Name
Init
D7
SFRGB1(1)
0
D6
SFRGB1(0)
0
D5
SRRGB1(1)
0
D4
SRRGB1(0)
0
D3
-
-
D2
TRGB1(2)
0
D1
TRGB1(1)
0
D0
TRGB1(0)
0
Function
0
1
SFRGB1(1)
SFRGB1(0)
Slope Down transition
0
0
0
0
1
Wave form cycle / 16
1
0
Wave form cycle / 8
1
1
Wave form cycle / 4
It is a theoretical value on logic control, and the reaction time of the analog section is
not included."Slope time" is the time from a slope start to a slope end.
SRRGB1(1)
SRRGB1(0)
Slope Up transition
0
0
0
0
1
Wave form cycle / 16
1
0
Wave form cycle / 8
1
1
Wave form cycle / 4
It is a theoretical value on logic control, and the reaction time of the analog section is not
included."Slope time" is the time from a slope start to a slope end.
TRGB1(2)
0
0
0
0
1
1
1
1
TRGB1(1)
0
0
1
1
0
0
1
1
TRGB1(0)
0
1
0
1
0
1
0
1
Wave form cycle
0.131 s
0.52 s
1.05 s
2.10 s
4.19 s
8.39 s
12.6 s
16.8 s
Setting time is counted based on the frequency of OSC. The above-mentioned value is a value at the time of Typ (1MHz).
When operating by the external clock, input frequency is a value at the time of Typ (250kHz).
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
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© 2011 ROHM Co., Ltd. All rights reserved.
10/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 03h
<R1 current 1setup >
BIT
Name
Init
D7
D6
IR11(6)
0
D5
IR11(5)
0
D4
IR11(4)
0
D3
IR11(3)
0
D2
IR11(2)
0
D1
IR11(1)
0
D0
IR11(0)
0
Adress 04h
Name
Init
D7
D6
IR12(6)
0
D5
IR12(5)
0
D4
IR12(4)
0
D3
IR12(3)
0
D2
IR12(2)
0
D1
IR12(1)
0
D0
IR12(0)
0
IR11(6) IR11(5) IR11(4)
IR11(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IR11(2)
0
0
・
・
1
1
IR11(1)
0
0
・
・
1
1
IR11(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
IR12(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
Function
0
-
1
-
IR12(6) IR12(5) IR12(4)
IR12(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IR12(2)
0
0
・
・
1
1
IR12(1)
0
0
・
・
1
1
<R1 Wave Pattern >
BIT
Name
Init
D7
D6
D5
D4
-
-
D3
PR1(3)
0
D2
PR1(2)
1
D1
PR1(1)
1
D0
PR1(0)
1
Adress 06h
1
-
<R1 current2 setup >
BIT
Adress 05h
Function
0
-
Function
0
PR1(3)
0
0
0
・
・
・
1
1
1
1
-
PR1(2)
0
0
0
・
・
・
1
1
1
PR1(1)
0
0
1
・
・
・
0
1
1
PR1(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern1
Pattern2
Pattern3
・
・
・
Pattern14
Pattern15
Pattern16
<G1 current1 setup >
BIT
Name
Init
D7
D6
IG11(6)
0
D5
IG11(5)
0
D4
IG11(4)
0
D3
IG11(3)
0
D2
IG11(2)
0
D1
IG11(1)
0
D0
IG11(0)
0
Function
0
-
1
-
IG11(6) IG11(5) IG11(4)
IG11(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IG11(2)
0
0
・
・
1
1
IG11(1)
0
0
・
・
1
1
IG11(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
11/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 07h
<G1 current2 setup >
BIT
Name
Init
D7
D6
-
-
IG12(6)
0
D5
IG12(5)
0
D4
IG12(4)
0
D3
IG12(3)
0
D2
IG12(2)
0
D1
IG12(1)
0
D0
IG12(0)
0
Adress
08h
Name
Init
D7
D6
D5
D4
-
-
D3
PG1(3)
0
D2
PG1(2)
1
D1
PG1(1)
1
D0
PG1(0)
1
IG12(6) IG12(5) IG12(4) IG12(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IG12(2)
0
0
・
・
1
1
IG12(1)
0
0
・
・
1
1
IG12(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
Function
0
PG1(3)
0
0
0
・
・
・
1
1
1
1
-
PG1(2)
0
0
0
・
・
・
1
1
1
PG1(1)
0
0
1
・
・
・
0
1
1
PG1(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern 1
Pattern 2
Pattern 3
・
・
・
Pattern 14
Pattern 15
Pattern 16
<B1 current1setup >
BIT
Name
Init
D7
D6
-
-
IB11(6)
0
D5
IB11(5)
0
D4
IB11(4)
0
D3
IB11(3)
0
D2
IB11(2)
0
D1
IB11(1)
0
D0
IB11(0)
0
Adress 0Ah
1
-
<G1 G1 Wave Pattern >
BIT
Adress 09h
Function
0
-
Function
0
-
1
-
IB11(6) IB11(5) IB11(4)
IB11(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IB11(2)
0
0
・
・
1
1
IB11(1)
0
0
・
・
1
1
IB11(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
IB12(0)
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
<B1 current2setup >
BIT
Name
Init
D7
D6
-
-
IB12(6)
0
D5
IB12(5)
0
D4
IB12(4)
0
D3
IB12(3)
0
D2
IB12(2)
0
D1
IB12(1)
0
D0
IB12(0)
0
Function
0
-
1
-
IB12(6) IB12(5) IB12(4)
IB12(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IB12(2)
0
0
・
・
1
1
IB12(1)
0
0
・
・
1
1
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
12/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 0Bh
<B1 Wave Pattern >
BIT
Name
Init
D7
D6
D5
D4
-
-
D3
PB1(3)
0
D2
PB1(2)
1
D1
PB1(1)
1
D0
PB1(0)
1
Adress 0Ch
Function
0
PB1(3)
0
0
0
・
・
・
1
1
1
1
-
PB1(2)
0
0
0
・
・
・
1
1
1
PB1(1)
0
0
1
・
・
・
0
1
1
PB1(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern1
Pattern2
Pattern3
・
・
・
Pattern14
Pattern15
Pattern16
<RGB2 time >
BIT
Name
Init
D7
SFRGB2(1)
0
D6
SFRGB2(0)
0
D5
SRRGB2(1)
0
D4
SRRGB2(0)
0
D3
-
-
D2
TRGB2(2)
0
D1
TRGB2(1)
0
D0
TRGB2(0)
0
Function
0
1
SFRGB2(1)
SFRGB2(0)
Slope Down transition
0
0
0
0
1
Wave form cycle / 16
1
0
Wave form cycle / 8
1
1
Wave form cycle / 4
It is a theoretical value on logic control, and the reaction time of the analog section is
not included.
"Slope time" is the time from a slope start to a slope end.
SRRGB2(1)
SRRGB2(0)
Slope up transition
0
0
0
0
1
Wave form cycle / 16
1
0
Wave form cycle / 8
1
1
Wave form cycle / 4
It is a theoretical value on logic control, and the reaction time of the analog section is not
included.
"Slope time" is the time from a slope start to a slope end.
TRGB2(2)
0
0
0
0
1
1
1
1
TRGB2(1)
0
0
1
1
0
0
1
1
TRGB2(0)
0
1
0
1
0
1
0
1
Wave form cycle
0.131 s
0.52 s
1.05 s
2.10 s
4.19 s
8.39 s
12.6 s
16.8 s
Setting time is counted based on the frequency of OSC. The above-mentioned value is a value at the time of Typ (1MHz).
When operating by the external clock, input frequency is a value at the time of Typ (250kHz)
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
13/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 0Dh
<R2 current 1setup>
BIT
Name
Init
D7
-
-
D6
IR21(6)
0
D5
IR21(5)
0
D4
IR21(4)
0
D3
IR21(3)
0
D2
IR21(2)
0
D1
IR21(1)
0
D0
IR21(0)
0
Adress 0Eh
Name
Init
D7
D6
-
-
IR22(6)
0
D5
IR22(5)
0
D4
IR22(4)
0
D3
IR22(3)
0
D2
IR22(2)
0
D1
IR22(1)
0
D0
IR22(0)
0
IR21(5)
IR21(4)
IR21(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IR21(2)
IR21(1)
IR21(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
Function
0
IR22(6)
IR22(5)
1
IR22(4)
IR22(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IR22(2)
IR22(1)
IR22(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
<R2 Wave Pattern setup>
BIT
Name
Init
D7
D6
D5
D4
-
-
D3
PR2(3)
0
D2
PR2(2)
1
D1
PR2(1)
1
D0
PR2(0)
1
Adress 10h
IR21(6)
1
-
<R2 current 2setup>
BIT
Adress 0Fh
Function
0
-
Function
0
PR2(3)
0
0
0
・
・
・
1
1
1
1
-
PR2(2)
0
0
0
・
・
・
1
1
1
PR2(1)
0
0
1
・
・
・
0
1
1
PR2(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern 1
Pattern 2
Pattern 3
・
・
・
Pattern 14
Pattern 15
Pattern 16
<G2 current 1setup>
BIT
Name
Init
D7
-
-
D6
IG21(6)
0
D5
IG21(5)
0
D4
IG21(4)
0
D3
IG21(3)
0
D2
IG21(2)
0
D1
IG21(1)
0
D0
IG21(0)
0
Function
0
IG21(6)
IG21(5)
1
IG21(4)
IG21(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IG21(2)
IG21(1)
IG21(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
14/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 11h
<G2 current 2setup>
BIT
Name
Init
D7
-
-
D6
IG22(6)
0
D5
IG22(5)
0
D4
IG22(4)
0
D3
IG22(3)
0
D2
IG22(2)
0
D1
IG22(1)
0
D0
IG22(0)
0
Adress 12h
Name
Init
D7
D6
D5
D4
-
-
D3
PG2(3)
0
D2
PG2(2)
1
D1
PG2(1)
1
D0
PG2(0)
1
IG22(5)
IG22(4)
IG22(3)
0
0
0
0
0
0
0
0
・
・
・
・
・
・
・
・
1
1
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
IG22(2)
IG22(1)
IG22(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
Function
0
PG2(3)
0
0
0
・
・
・
1
1
1
1
-
PG2(2)
0
0
0
・
・
・
1
1
1
PG2(1)
0
0
1
・
・
・
0
1
1
PG2(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern 1
Pattern 2
Pattern 3
・
・
・
Pattern 14
Pattern 15
Pattern 16
<B2 current 1setup>
BIT
Name
Init
D7
-
-
D6
IB21(6)
0
D5
IB21(5)
0
D4
IB21(4)
0
D3
IB21(3)
0
D2
IB21(2)
0
D1
IB21(1)
0
D0
IB21(0)
0
Adress 14h
IG22(6)
1
-
<G2 Wave Pattern setup >
BIT
Adress 13h
Function
0
-
Function
0
IB21(6)
IB21(5)
1
IB21(4)
IB21(3)
0
0
0
0
0
0
・
・
・
・
・
・
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
0
0
・
・
1
1
IB21(2)
IB21(1)
IB21(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
<B2 current 2setup>
BIT
Name
Init
D7
-
-
D6
IB22(6)
0
D5
IB22(5)
0
D4
IB22(4)
0
D3
IB22(3)
0
D2
IB22(2)
0
D1
IB22(1)
0
D0
IB22(0)
0
Function
0
IB22(6)
IB22(5)
1
IB22(4)
IB22(3)
0
0
0
0
0
0
・
・
・
・
・
・
1
1
1
1
1
1
At RGBISETpin 120kΩ connection
0
0
・
・
1
1
IB22(2)
IB22(1)
IB22(0)
0
0
・
・
1
1
0
0
・
・
1
1
0
1
・
・
0
1
Current
0
0.2mA
0.2mA
step
25.2mA
25.4mA
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
15/27
2011.04 - Rev.A
BD2802GU
Technical Note
Adress 15h
<B2 Wave Pattern setup >
BIT
Name
Init
D7
D6
D5
D4
-
-
D3
PB2(3)
0
D2
PB2(2)
1
D1
PB2(1)
1
D0
PB2(0)
1
Function
PB2(3)
0
0
0
・
・
・
1
1
1
0
1
-
-
PB2(2)
0
0
0
・
・
・
1
1
1
PB2(1)
0
0
1
・
・
・
0
1
1
PB2(0)
0
1
0
・
・
・
1
0
1
Wave
Pattern 1
Pattern 2
Pattern 3
・
・
・
Pattern 14
Pattern 15
Pattern 16
＊Refer to "●Use of a RGB wave setup " for the detailed function of each register of this page.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
16/27
2011.04 - Rev.A
BD2802GU
Technical Note
 RGB LED Driver Operation Description
- Two drivers “RGB1 (R1LED, G1LED, B1LED)” and “RGB2 (R2LED, G2LED, B2LED)” are mounted.
- A slope function is incorporated to control drivers independently.
- Refer to  RGB Waveform Setting for more information about output waveform setting.
- The LED current can be set via a resistance value (RISET) to be connected to the RGBISET terminal. The maximum
current value can be derived from the following expression:
ILEDmax [A] = 3.048 / RISET [kΩ] (Typ)
However, this setting must be made so that the maximum current value can be less than or equal to 30.48mA. In
addition, the RGBISET terminal has an overcurrent protection circuit to prevent the excessive LED current from flowing
for low impedance to the ground.
- Note that the setting voltage shall be higher than or equal to a saturation voltage (0.2V) in the constant current circuit.
When LED Vf is large, the LED destination shall be connected to another step-up circuit.
RGB*EN
または
RGB*EN
RGB*OS
or
RFB*OS
Ton
(Max:20ms)
LED 電流
LED current
-
The LED destination is fixed before on (RGB*EN=Hi or RGB*OS=Hi).
VLED
VLED
RGB*EN
Or
RGB*OS
RGB*EN
Or
RGB*OS
●The synchronism of RGB1/RGB2
The period of RGB1 and RGB2 and start, stop timing can be set up independently.
When synchronizes RGB1 and RGB2, You must start an internal counter at the same time under the state of resetting.
(Internal Counter are prepared for each of RGB1 and RGB2, so You must reset both.)
<How to reset internal Counter>
Inside Counter can be reset by carrying out one of following actions.
•
•
•
Reset by hard reset (RSTB_IL). (RGB1, RGB2 is reset together.)
Reset by soft reset. (RGB1, RGB2 is reset together.)
It is written register of the current setup (I1・I2), the slope setup, the period setup and the pattern setup.
Internal Counter of RGB1 is reset when it is written between Address=0Bh from 02h.
Internal Counter of RGB2 is reset when it is written between Address=15h from 0Ch.
Counter is reset as to overwriting the same value.
Note)
Internal Counter isn't reset if write RGB1EN =L and RGB2EN =L. (Address=01h).
When it write RGB1EN=L (RGB2EN=L), inside Counter is held, and IC will operate from the held state at next restart.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
17/27
2011.04 - Rev.A
BD2802GU
Technical Note
●RGB Waveform Setting
Various kinds of RGB control can be implemented by designating waveform cycles, waveform patterns, current settings 1, 2
and rising/falling slope times.
To activate a RGB waveform, a continuous operation via RGB*EN or a single-shot operation via RGB*OS can be selected.
In addition, when control via the external terminal RGB*CNT is enabled via RGB*MEL, the corresponding LED can be lit in
synchronization with the external signal.
1. Waveform cycle
 A single cycle time is set for a waveform pattern.
 This setting can be made independently for RGB1 and RGB2.
2. Waveform pattern
 A pattern in a waveform cycle is set.
 Sixteen types of waveform patterns can be set in units of waveform patterns.
 For concrete waveform patterns, refer to the timing diagram shown on the next page.
3. Current settings 1 and 2 (I1, I2)
 Two currents in a waveform pattern are set.
 When the maximum current value is 25.4mA, it is possible to set the current ranging from 0 to 25.4mA with an
increment of 0.2mA (128 steps).
 The polarity of a waveform is determined by the greater-than/ less-than relationship in the current setting.
 This setting can be made in units of terminals.
4. Rising/falling slope time
 A current change time during switching between current settings 1 and 2 is set.
 A time per step (0.2mA) is calculated based on a difference between the currents selected in current settings 1, 2
and a setting slope time.
 For this reason, a time per step (0.2mA) is short when a difference between setting currents I1 and I2 is large. In
contrast, it is long when a difference between setting currents I1 and I2 is small.
 Regardless of current settings 1 and 2, a rising slope time applies at current increase and a falling slope time applies
at current decrease. For concrete waveform images, refer to the timing diagram shown on the next page.
5. External terminal synchronization control
When control via the external terminal RGB*CNT is enabled via RGB*MEL, lighting is enabled if the input external signal
goes “H.” In contrast, it is disabled if the external input signal goes “L.” In this way, synchronization with the external
signal is enabled so that LED can be blinked in conjunction with a ringing tone (a melody signaling a ringtone).
A RGB thin line indicates an image where
external terminal control does not take
place.
Waveform cycle
R*LED
G*LED
B*LED
RGB*CNT
RGB*MEL
External terminal control
is enabled.
www.rohm.com
© 2011 ROHM Co., Ltd. All rights reserved.
Remains “Enabled” with
RGB*MEL=1 and
RGB*CNT=H
18/27
External terminal
control is disabled.
2011.04 - Rev.A
BD2802GU
Technical Note
Wave cycle
Register data
Wave pattern 1
(00h)
Wave pattern2
(01h)
Wave pattern 3
(02h)
Wave pattern 4
(03h)
Wave pattern 5
(04h)
Wave pattern 6
(05h)
Wave pattern 7
(06h)
Wave pattern 8
(07h)
Wave pattern 9
(08h)
Wave pattern 10
(09h)
Wave pattern 11
(0Ah)
Wave pattern 12
(0Bh)
Wave pattern 13
(0Ch)
Wave pattern 14
(0Dh)
Wave pattern 15
(0Eh)
Wave pattern 16
(0Fh)
I1
I2
I1
I2
I1
I2
I1
I2
I1
I2
I1
I2
I1
I2
I1
I1
I2
I1
I1
I1
I2
I2
I1
I1
I2
I2
I1
I1
I1
I2
I2
I1
I1
I2
I1
I1
I1
I1
I2
I2
I1
I2
I1
I1
I2
I1
I2
（ex）The image of current change of Wave pattern 11
Slope Down transition
Current 2(I2)
Slope uptransition
Current 1(I1)
RGB wave setting timing diagram
6. Clock I/O
A reference clock I/O function is mounted in this IC chip. When two IC chips are used to extend an illumination
capability, clock supply to the other RGB LED driver can be accomplished for synchronization with this LSI chip.
This setting can be made via the register.
Clock output can be made with CLKEN=1 and CLKMD=1.
Register
CLKIO terminal state
CLKEN
CLKMD
0
0/1
Input
1
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0
1
Input
Output
19/27
Clock reception
Does not receive external clocks.
Operates on external clocks.
-
2011.04 - Rev.A
BD2802GU
Technical Note
●When two BD2802GU drivers are used and the clock is shared by CLKIO:
Because a sequence is already programmed within an IC chip for RGB falling, “Enable” shall be set to “OFF” and
clock supply shall be continued for at least three clocks so that operations can be performed using external clocks.
Enable
マスター側
Master enabled
Slave enabled
Enable
スレーブ側
(min=0ms)
min=スレーブ側入力クロックの
min = slave input clock (3 clocks) 3 クロック分
(マスター側のクロックを使用している場合は
min=15μs)
(For master clocks in use: min = 15 s)
Master: Chip using CLKIO as output
Slave: Chip using CLKIO as input
*Even in independent slave mode, its setting “Enable” shall be reset to “OFF” and then clock supply must be
continued for 3 clocks or more.
Clock I/O switching shall be avoided during RGB operation.
Enable: CLKEN, RGB1EN, RGB2EN, RGB1OS, RGB2OS
- Setting example
Master side (clock output side)
RGB waveform setting

Slave side
(clock input side)
RGB waveform setting

Master side Clock output setting
CLKEN=1, CLKMD=1
… Performs clock output.

Slave side
Clock input setting
CLKEN=1, CLKMD=0
… Allows clock reception.

Master side RGB lighting


This duration shall be short as much as possible.

Slave side
RGB lighting
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© 2011 ROHM Co., Ltd. All rights reserved.
20/27
2011.04 - Rev.A
BD2802GU
Technical Note
7. RGB waveform setting examples
1】ノーマル
[Example
1] Normal
operation
【例
動作
4】16Hz
[Example
4] 16Hz
【例
動作 operation
波形周期
Waveform
cycle
R*LED
R*LED
G*LED
G*LED
B*LED
B*LED
RGB*EN=1
RGB*EN=0
RGB*EN=1
Selecting a waveform pattern 8 causes a continuous
normal operation to take place through the setting
current 1.
2】ブリンク動作
【例
[Example
2] Blinking
5】4 連単発
【例
[Example
5] Continuous lighting of four
LEDs
波形周期
Waveform
cycle
R*LED
G*LED
G*LED
B*LED
B*LED
RGB*EN=0
This example shows that lighting occurs continuously in
the order of white, red, red and red. To achieve this,
waveform patterns 16, 1 and RGB*OS single cycle
operation need to be combined.
6】7 6]
【例
色変色スロープ
[Example
7-color change slope
operation
波形周期
Waveform
cycle
R*LED
R*LED
G*LED
G*LED
B*LED
B*LED
RGB*EN=1
RGB*EN=０
RGB*EN=1
When a rising/falling slope time is longer than the
setting made in example 2, a continuous color change
is made by slope operation.
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波形周期
Waveform
cycle
RGB*OS=1
Setting a rising/falling slope time to “0” causes blinking
to take place. Phase switching takes place via the
setting currents of R and G.
【例３】スロープ動作
[Example 3] Slope operation
RGB*EN=0
Combining the settings of a waveform pattern 11 and a
waveform cycle 131ms causes blinking at a rate of
15.3Hz (approx. 16Hz).
R*LED
RGB*EN=1
波形周期
Waveform
cycle
波形周期
Waveform
cycle
RGB*EN=０
R, G and B waveform patterns are set in a way that any
of R, G and B changes constantly.
21/27
2011.04 - Rev.A
BD2802GU
Technical Note
8. RGB slope waveforms
- Example of waveform at activation
Current setting: I1 < I2
(R G B*EN = 1)
I2
I1
(O FF)
(R G B*O S = 1)
R G B*EN or R G B*O S = 1
R G B*EN = 0
Current setting: I1 > I2
I1
(RG B*EN = 1)
I2
(O FF)
(R G B*O S = 1)
R G B*EN or R G B*O S = 1
R G B*EN = 0
- Current difference in each channel (example)
I2 ( A )
I2 ( B )
Transition takes place in units of steps but the time
per step is set based on internal calculation so that
the slope arrival time is quasi-equal.
I1 (B )
I1 ( A )
Slope duration
9. Setting change in slope duration
A slope operation is performed by an internal sequencer.
When an attempt is made to change the setting in a slope duration, the active slope operation is reset and a newly set
slope operation is restarted.
In this case, however, LED lighting stops for a maximum of 16.4ms (OSC frequency=typ) for synchronization with the
internal clock until the operation is restarted.
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22/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Description of other operations
1. Reset
There are two types of reset: software reset and hardware reset.
(1) Software reset
- Setting the register (SFTRST) to “1” causes all the registers to be initialized.
- The registers subject to software reset automatically return to zero (Auto Return 0).
(2) Hardware reset
- Changing the RESETB terminal setting from “H” to “L” causes a state subject to hardware reset.
- Attempting hardware reset causes the states of all registers and output terminals to be initialized to their initial
values, so that address reception is entirely stopped.
- Attempting reset in the hardware reset state causes the RESETB terminal state to change from “L” to “H” and vice versa.
- The RESETB terminal is provided with a filter circuit and a duration of 5µs or less with the terminal set to “L” is not
recognized as hardware reset.
(3) Reset sequence
- When hardware reset is attempted during software reset, software reset is already cleared when hardware reset is
cleared (because the software reset initial value is 0).
2. Thermal shutdown
The thermal shutdown is effective for LED and OSC portions.
The thermal shutdown function is activated when the detected temperature is approx. 195C.
The detected temperature has a hysteresis and the detection cancel temperature is approx. 175C (reference value in design).
3. I/O portion
While the RESETB terminal is in “L” state, no input signal is propagated to the IC logic portion because SDA and SCL
input buffer operations are all stopped.
When RESETB=L, output is fixed at “H.”
Level shifter
SCL
(SDA)
Logic
EN
RESETB
Special care should be taken because a current path may be formed via a terminal protection diode, depending on an I/O
power-on sequence or an input level.
4. Power on/off sequence
Voltage shall be applied as follows at driver activation. When a delay element is connected to a VIO voltage source
and a reset cancel signal is input to the RESETB terminal, special care should be taken to the rising time of VIO voltage
to delay the RESETB signal without fail.
VBAT
T VBATOFF
VIO
T R STB=m in 0.1m s
T R ST=m in 0.1m s
RESETB
T AC SS=m in 0.1m s
control
レRegister
ジ ス タ制
御
Register 不
control
可 disabled
Register 可
control
能 enabled
Register 不
control
可 disabled
5. Terminating the unused terminals
Be sure to set the test terminals and unused terminals as summarized in the following table.In addition, refer to the
preceding equivalent circuit and terminate the above terminals in a way that no problem occurs during actual use.
T1, T2, T3, T4
Test input terminals. Short-circuit these terminals to GND.
Short-circuit these terminals to GND.
LED terminals not to be used
In this case, don’t set the registers related to LEDs not to be used.
RGB1CNT, RGB2CNT
Short-circuit these terminals to GND.(Built-in pull-down resistance)
CLKIO
Short-circuit this terminal to GND.(Built-in pull-down resistance)
ADDSEL
Be sure to short-circuit this terminal to VBAT or GND.
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23/27
2011.04 - Rev.A
BD2802GU
Technical Note
●PCB pattern of the Power dissipation measuring board
1st layer(component)
2nd layer
3rd layer
4th layer
5th layer
6th layer
7th layer
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8th layer (solder)
24/27
2011.04 - Rev.A
BD2802GU
Technical Note
●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) Power supply and ground line
Design PCB pattern to provide low impedance for the wiring between the power supply and the ground lines. Pay attention to
the interference by common impedance of layout pattern when there are plural power supplies and ground lines.
Especially, when there are ground pattern for small signal and ground pattern for large current included the external
circuits, please separate each ground pattern. Furthermore, for all power supply pins to ICs, mount a capacitor between the
power supply and the ground pin. At the same time, in order to use a 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.
(3) Ground voltage
Make setting of the potential of the ground pin so that it will be maintained at the minimum in any operating state. Furthermore,
check to be sure no pins are at a potential lower than the ground voltage including an actual electric transient.
(4) Short circuit between pins 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 pins or between
the pin and the power supply or the ground pin, the ICs can break down.
(5) Operation in strong electromagnetic field
Be noted that using ICs in the strong electromagnetic field can malfunction them.
(6) Input pins
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 pin.
Therefore, pay thorough attention not to handle the input pins, such as to apply to the input pins a voltage lower than the
ground respectively, so that any parasitic element will operate. Furthermore, do not apply a voltage to the input pins when no
power supply voltage is applied to the IC. In addition, even if the power supply voltage is applied, apply to the input pins a
voltage lower than the power supply voltage or within the guaranteed value of electrical characteristics.
(7) 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.
(8) Thermal shutdown circuit (TSD)
This LSI builds in a thermal shutdown (TSD) circuit. When junction temperatures become detection 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.
(9) Thermal design
Perform thermal design in which there are adequate margins by taking into account the permissible dissipation (Pd) in
actual states of use.
(10) About the pin for the test, the un-use pin
Prevent a problem from being in the pin for the test and the un-use pin under the state of actual use. Please refer to a
function manual and an application notebook. And, as for the pin that doesn't specially have an explanation, ask our
company person in charge.
(11) About the rush current
Because the rush current flows momentarily for internal logic instability caused by a power-on sequence or delay,
special care should be taken to the power supply coupling capacity, power supply, ground pattern wiring width and
wiring.
(12) About descriptions given in this document
Though the function description and application node are design documents prepared for application design, we don’t
take liability for descriptions given in these documents. Be sure to decide applications after thoroughly investigating
and evaluating the external devices as well as this BS2802GU LED driver.
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© 2011 ROHM Co., Ltd. All rights reserved.
25/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Power Dissipation (On the ROHM’s standard board)
1.6
Power Dissipation Pd （W)
1.4
1250mW
1.2
Information of the ROHM’s standard board
Material : glass-epoxy
Size : 50mm×58mm×1.75mm (8Layer)
Pattern of the board: Refer to it that goes later.
1.0
0.8
0.6
0.4
0.2
0.0
0
25
50
75
100
125
150
Ta（℃）
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26/27
2011.04 - Rev.A
BD2802GU
Technical Note
●Ordering part number
B
D
2
Part No.
8
0
2
G
Part No.
2802
U
-
Package
GU : VCSP85H2
E
2
Packaging and forming specification
E2: Embossed tape and reel
VCSP85H2 (BD2802GU)
2.8±0.1
1.0MAX
1PIN MARK
0.25± 0.1
2.8± 0.1
<Tape and Reel information>
(φ0.15)INDEX POST
B
1
0.4±0.1
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
)
0.4± 0.1
A
E
D
C
B
A
3000pcs
P=0.5 × 4
0.08 S
0.05 A B
Embossed carrier tape
Quantity
Direction
of feed
S
24- φ 0.30±0.05
Tape
2 3 4 5
P=0.5×4
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© 2011 ROHM Co., Ltd. All rights reserved.
1pin
(Unit : mm)
Reel
27/27
Direction of feed
∗ Order quantity needs to be multiple of the minimum quantity.
2011.04 - Rev.A
Notice
Notes
No copying or reproduction of this document, in part or in whole, is permitted without the
consent of ROHM Co.,Ltd.
The content specified herein is subject to change for improvement without notice.
The content specified herein is for the purpose of introducing ROHM's products (hereinafter
"Products"). If you wish to use any such Product, please be sure to refer to the specifications,
which can be obtained from ROHM upon request.
Examples of application circuits, circuit constants and any other information contained herein
illustrate the standard usage and operations of the Products. The peripheral conditions must
be taken into account when designing circuits for mass production.
Great care was taken in ensuring the accuracy of the information specified in this document.
However, should you incur any damage arising from any inaccuracy or misprint of such
information, ROHM shall bear no responsibility for such damage.
The technical information specified herein is intended only to show the typical functions of and
examples of application circuits for the Products. ROHM does not grant you, explicitly or
implicitly, any license to use or exercise intellectual property or other rights held by ROHM and
other parties. ROHM shall bear no responsibility whatsoever for any dispute arising from the
use of such technical information.
The Products specified in this document are intended to be used with general-use electronic
equipment or devices (such as audio visual equipment, office-automation equipment, communication devices, electronic appliances and amusement devices).
The Products specified in this document are not designed to be radiation tolerant.
While ROHM always makes efforts to enhance the quality and reliability of its Products, a
Product may fail or malfunction for a variety of reasons.
Please be sure to implement in your equipment using the Products safety measures to guard
against the possibility of physical injury, fire or any other damage caused in the event of the
failure of any Product, such as derating, redundancy, fire control and fail-safe designs. ROHM
shall bear no responsibility whatsoever for your use of any Product outside of the prescribed
scope or not in accordance with the instruction manual.
The Products are not designed or manufactured to be used with any equipment, device or
system which requires an extremely high level of reliability the failure or malfunction of which
may result in a direct threat to human life or create a risk of human injury (such as a medical
instrument, transportation equipment, aerospace machinery, nuclear-reactor controller, 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.
If you intend to export or ship overseas any Product or technology specified herein that may
be controlled under the Foreign Exchange and the Foreign Trade Law, you will be required to
obtain a license or permit under the Law.
Thank you for your accessing to ROHM product informations.
More detail product informations and catalogs are available, please contact us.
ROHM Customer Support System
http://www.rohm.com/contact/
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R1120A