T6316B-20DG [ETC]
Low-Dropout, Constant-Current White LED Bias Supply; 低压差,恒定电流白光LED偏置电源型号: | T6316B-20DG |
厂家: | ETC |
描述: | Low-Dropout, Constant-Current White LED Bias Supply |
文件: | 总6页 (文件大小:40K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
TE
tmCH
Preliminary T6316A/B
Low-Dropout, Constant-Current
White LED Bias Supply
FEATURES
GENERAL DESCRIPTION
The T6316A/B low-dropout bias supply for
white LEDs is a high-performance alternative
to the simple ballast resistors used in
conventional white LED designs. The T6316A
uses a single resistor to set the bias current for
four LEDs, which are matched to 3%. The
T6316B build in internal resistor to set the bias
current for four LED. The T6316A/B
advantages over ballast resistors include
significantly better LED to LED bias matching,
much lower bias variation with supply voltage
variation, significantly lower dropout voltage,
and in some applications, significantly
improved efficiency. The T6316A/B is
available in SOP-8 package and lead-free.
• Up to 400mA LED Bias Current
• 3% LED Current Matching
• Simple LED Brightness Control
• Low 0.05uA Shutdown Current
• 2.7V to 5V Supply Voltage Range
• SOP-8 Package and Lead-free
• VSET Resistor Option :
T6316A : External Resistor
T6316B : 20, 85, 100, 125, 150, 175, 200,
250, 300 and 350mA Output
Current Option by Internal
Resistor
• Build in Thermat Protect 160 °C
Applications
PART NUMBER EXAMPLES
• Portable Communication Devices
• Handheld Electronics
• LED/Display Back Light Driver
• Lightings
Vset
resistor
External
Output
Current
PART NO.
T6316A-D
PACKAGE
SOP-8
-
SOP-8
lead-free
T6316A-DG
T6316B-20D
T6316B-20DG
T6316B-75D
T6316B-75DG
-
External
SOP-8
20mA Internal
20mA Internal
75mA Internal
75mA Internal
SOP-8
lead-free
SOP-8
SOP-8
lead-free
T6316B-350D
SOP-8 350mA Internal
SOP-8
T6316B-350DG
350mA Internal
lead-free
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 1
Publication Date: JUN. 2006
Revision: B
TE
tmCH
Preliminary T6316A/B
PIN ARRANGEMENT(Top view)
1
2
3
4
L E D 1
L E D 2
L E D 3
L E D 4
8
7
6
5
V S E T
E N
V D D
V S S
SOP-8
T6316A-D
1
2
3
4
L E D 1
L E D 2
L E D 3
L E D 4
8
7
6
5
E N
V D D
V S S
V S S
SOP-8
T6316B-D
PIN DESCRIPTION
T6316A
T6316B
DESCRIPTION
SYMBOL
LED 1 Cathode Connection. Current flowing into LED1 is 270/250 times the current
flowing into SET. LED1 is high impedance when EN is low.
LED 2 Cathode Connection. Current flowing into LED1 is 270/250 times the current
flowing into SET. LED2 is high impedance when EN is low.
LED 3 Cathode Connection. Current flowing into LED1 is 270/250 times the current
flowing into SET. LED3 is high impedance when EN is low.
LED 4 Cathode Connection. Current flowing into LED1 is 270/250 times the current
flowing into SET. LED4 is high impedance when EN is low.
Ground
LED1
LED2
LED3
LED4
1
2
3
4
1
2
3
4
VSS
VDD
EN
5
6
7
5,6
7
8
Power supply
Enables PN6316A/B signal , H: Ative , L : Power Down .
VSET terminal is used to connect an external resistor to set output current.
The current flowing into VSET sets the bias current into
each LED by ILED_= 250 x ISET.
VSET
8
-
VSET is internally biased to 0.306V. VSET is high impedance when EN is low.
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 2
Publication Date: JUN. 2006
Revision: B
TE
tmCH
Preliminary T6316A/B
ABSOLUTE MAXIMUM RATINGS
Parameter
Symbol
Value
-0.3 to 6
-40 to +85
300
Unit
V
Voltage on any pin relative to GND
Operating Temperature Rang
VIN
T
A
°C
°C
°C
W
Maximum Soldering Temperature (at leads, 10 sec)
Storage Temperature Rang
TLEAD
T
S
-65 to +150
1
Continuous Power Dissipation ( T = +70°C )
A
Electrical Characteristics
(TA = -40 to 85°C unless otherwise noted. Typical values are at TA =25°C,
VEN =3.3V, VLED1 = VLED2= VLED3= VLED4= 1V)
Symbol
Description
Conditions
Min. Typ. Max Unit
2.7
VEN Operating voltage range
ISET SET input current range
EN is power supply input
5
V
1400 1600 uA
T6316A
T6316B
270
A/A
250
ISETR SET to LED current ratio
ILED / ISET, SET
I
=400uA
VSET SET bias voltage
ISET=400uA, no loading
0.306
3
V
ICM LED to LED current matching ISET=400uA, 100mA loading
%
ILED Maximum LED sink current
Each LED
350 400 mA
LED leakage current in
shutdown
VLED1=VLED2=VLED3=VLED4= 3.3V,
EN=GND, TA=+25°C, each LED
ILSD
0.01
1
uA
VIH Input high voltage
VIL Input low voltage
VEN >VIH for enable, VDD=5V
VEN <VIL for disable, VDD=5V
2.0
V
V
0.8
TTP
160
Thermat Protect
°C
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 3
Publication Date: JUN. 2006
Revision: B
TE
tmCH
Preliminary T6316A/B
Functional Description
Applications Information
The T6316A/B provides constant current
bias supply for white LED designs. The
T6316A uses a single resistor to set the bias
current for up to four LEDs. LED bias
currents are matched to 3%. The T6316B
build in internal resistor to set the bias current
for four LED. The T6316A/B offers several
advantages over using ballast resistors, such
as improved LED to LED brightness
matching, lower bias variation with supply
voltage changes, significantly lower dropout
voltage, and in some applications,
significantly improved efficiency.
Very Low-Cost, High-Efficiency Solution .
A battery (single Li+ or three NiMH cells)
powers the LEDs directly. This is the least
expensive and most efficient architecture. Due
to the high forward voltage of white LEDs,
the LED brightness may dim slightly at the
end of battery life. The T6316A/B current
regulating architecture and low dropout
greatly minimize this effect compared to
using simple ballast resistors. The enable
function of the T6316A/B turns on and off the
LEDs.
Enable Input
EN powers the input of the T6316A/B.
Drive EN high (> 2.0V) to enable the device;
drive EN low (< 0.8V) to disable the device.
Driving EN low forces LED1, LED2, LED3,
LED4 and SET into a high-impedance state.
Setting the Output Current
SET controls the LED bias current. Current
flowing into LED1, LED2, LED3 and LED4
is 270/250 times greater than the current
flowing
into SET. Set the output current as follows:
T6316A
ILED = 270 (0.306V / RSET )
T6316B
ILED = 250 (0.306V / RSET )
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 4
Publication Date: JUN. 2006
Revision: B
TE
tmCH
Preliminary T6316A/B
TYPICAL APPLICATION CIRCUITS
V +
V D D
V D D L E D 1 L E D 2 L E D 3 L E D 4
E N
O N
O F F
T 6 3 1 6 A
G N D
S E T
R
V +
V D D
O F F
V D D L E D 1 L E D 2 L E D 3 L E D 4
O N
E N
T 6 3 1 6 B
G N D
Very low-cost, high-efficiency solution
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 5
Publication Date: JUN. 2006
Revision: B
TE
tmCH
Preliminary T6316A/B
PACKAGE DIMENSIONS
8-LEAD SOP
B
B 1
K
T h e rm a l P a d *
J
A 1
A
C 1
C
C 2
F
D
E
H
Dimension in mm
Dimension in inch
Symbol
Min.
5.70
3.75
-
-
-
1.35
0.10
0.31
0.30
0.10
Typ.
6.00
3.95
-
1.27
-
Max.
6.30
4.10
5.13
-
1.80
1.75
0.25
0.51
0.70
0.25
Min.
Typ.
0.236
0.156
-
0.050
-
Max.
0.248
0.164
0.202
-
0.071
0.069
0.004
0.020
0.028
0.010
A
A1
B
B1
C
C1
C2
D
E
F
J
K
0.224
0.148
-
-
-
0.052
0.001
0.012
0.012
0.004
1.55
-
0.061
-
0.41
0.50
0.15
2.23 REF
2.97 REF
0~8°
0.016
0.020
0.006
0.088 REF
0.117 REF
0~8°
H
*Note :
The thermal pad on the IC’s bottom has to be mounted on the copper foil.
To eliminate the noise influence, the thermal pad is suggested to be connected to GND on PCB.
In addition, desired thermal conductivity will be improved, if a heat-conducting copper foil on
PCB is soldered with thermal pad. The thermal pad enhances the power dissipation. As a result, a
large amount of current can be sunk safely in one package.
TM Technology Inc. reserves the right
to change products or specifications without notice.
P. 6
Publication Date: JUN. 2006
Revision: B
相关型号:
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