- 您现在的位置：买卖IC网 > Datasheet目录306 > A6268KLPTR-T (Allegro Microsystems Inc)IC LED CTLR AUTOMOBILE 16TSSOP Datasheet资料下载
参数资料
| 型号： | A6268KLPTR-T |
| 厂商： | Allegro Microsystems Inc |
| 文件页数： | 10/19页 |
| 文件大小： | 0K |
| 描述： | IC LED CTLR AUTOMOBILE 16TSSOP |
| 标准包装： | 1 |
| 恒定电流： | 是 |
| 拓扑： | 低端，PWM，SEPIC，降压（降压），升压（升压） |
| 输出数： | 1 |
| 内部驱动器： | 无 |
| 类型 - 主要： | 车载，背光 |
| 频率： | 100kHz ~ 700kHz |
| 电源电压： | 5 V ~ 50 V |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-TSSOP（0.173"，4.40mm）裸露焊盘 |
| 供应商设备封装： | 16-TSSOP-EP |
| 包装： | 标准包装 |
| 工作温度： | -40°C ~ 150°C |
| 其它名称： | 620-1473-6 |
A6268
Automotive High Current LED Controller
LED Current Level The LED current is determined by a
Provided this is low, then the complete circuit may remain con-
combination of the LED sense resistor, R SL , the LED current
threshold voltage, V IDL , and the voltage between the IREF pin
and GND ( V IREF ).
The 100% current level, when the IREF pin is connected to
VREG, is defined as:
I LED (max) = V IDL / R SL
(2)
nected to the power supply under all conditions. Note that the
disable time is derived from the oscillator period by a ratio of
32,768:1, so any variation in the oscillator frequency will change
the disable time. For the default switching frequency of 350kHz,
this means the disable time would be:
t DIS = 32,768 × ( 1 / 350 × 10 3 ) = 94 ms (4)
If V IREF is less than 1 V then the 100% current level is defined as:
I LED (max) = V IREF / (10 × R SL ) (3)
This feature provides direct analog dimming using a voltage from
0 to 1 V. This can be used for a number of different functions:
? To provide intensity matching between modules or groups of
Oscillator The main oscillator may be configured as a clock
source or it may be driven by an external clock signal. The oscil-
lator is designed to run between 100 and 700 kHz.
When the oscillator is configured as a clock source, the frequency
is controlled by a single external resistor, R OSC (k Ω ), between the
OSC pin and the GND pin. The oscillator frequency is approxi-
LEDs in critical display or backlighting applications.
? To provide a soft start, by connecting a capacitor from IREF to
mately:
f OSC = 21700 / R OSC
(kHz) (5)
GND and a resistor from IREF to VREG, or one-step dimming
by use of a single logic control.
? To reduce the LED current during cold-crank conditions, thus
avoiding overstressing the power components
LED Brightness: PWM Dimming LED brightness can
be controlled by changing the current, which affects the light
intensity. However in some applications, for example with amber
LEDs, this will have some effect on the color of the LEDs.
In these cases it is more desirable to control the brightness by
switching the fixed LED current with a pulse width modulated
signal. This allows the LED brightness to be set with little effect
on the LED color and intensity and allows direct digital control
of the LED brightness.
A PWM signal can be applied to the EN input to enable PWM
dimming. The period of this signal should be less than the
minimum disable time, t DIS . During PWM dimming, the A6268
switches the LED current between 100% and 0% of the full cur-
rent. Note that during PWM dimming, the gate drive is disabled
when EN is low. The rate of change of the LED current is also
limited, to reduce any large variations in the input current.
Figure 2 shows the resulting f OSC for various values of R OSC .
If the OSC pin is connected to VREG or GND, the oscillator
frequency will be set internally to approximately 350 kHz.
When an external clock source is used to drive the OSC pin, it
can synchronize a number of A6268s operating together. This
ensures that only a single fundamental frequency is detectable
on the supply line, thus simplifying the design of any required
EMC filter. The disadvantage of using a single external clock
source is that all controllers will be switching current from the
supply at the same time. However, this effect may be reduced,
and the EMC performance may be further enhanced, by using
700
600
500
400
300
200
Sleep Mode If EN is held low for longer than the disable time,
t DIS , then the A6268 will shut down and put all sections into a
low-power sleep mode. In this mode the bias current is typically
100
30
50
70 90 110 130 150 170
External Resistor Value, R OSC (k Ω )
190
210
less than 4 μ A. In the buck-boost configuration the only leakage
path remaining will be the path through the MOSFET.
Figure 2. Internal oscillator frequency when set by R OSC
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
10
相关PDF资料 |
PDF描述 |
|---|---|
| A6280EA-T | IC LED DRIVER PWM CONTROL 16-DIP |
| A6281EESTR-T | IC LED DRIVER PWM CONTROL 16-QFN |
| A6282ELPTR-T | IC LED DRIVER LINEAR 24-TSSOP |
| A8431EEHTR-T | IC LED DRVR WHITE BCKLGHT 6-MLP |
| A8500EECTR-T | IC LED DRVR WHT/RGB BCKLGT 26QFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| A6269 | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:Automotive LED Array Driver |
| A6269KLJTR-T | 制造商:Allegro MicroSystems 功能描述:TWO CHANNEL LINEAR LED DRIVER 制造商:ALLEGRO MICROSYSTEMS, LLC 功能描述:IC LED DRVR AUTOMOTIVE 8SOICN |
| A626A | 功能描述:ADAPTER PROGRAMMER 32-SSOP RoHS:否 类别:编程器，开发系统 >> 过时/停产零件编号 系列:- 标准包装:1 系列:- 类型:MCU 适用于相关产品:Freescale MC68HC908LJ/LK（80-QFP ZIF 插口） 所含物品:面板、缆线、软件、数据表和用户手册 其它名称:520-1035 |
| A62710-000 | 制造商:TE Connectivity 功能描述:TXR21AB00-0805BI |
| A6271KLPTR-T | 功能描述:LED Driver IC 1 Output DC DC Controller SEPIC, Step-Down (Buck), Step-Up (Boost) Analog, Internal or External PWM Dimming 16-eTSSOP 制造商:allegro microsystems, llc 系列:汽车级，AEC-Q100 包装:剪切带（CT） 零件状态:有效 类型:DC DC 控制器 拓扑:SEPIC，降压（降压），升压（升压） 内部开关:无 输出数:1 电压 - 供电（最低）:4.2V 电压 -?供电（最高）:50V 电压 - 输出:- 电流 - 输出/通道:- 频率:700kHz 调光:模拟，PWM 应用:汽车级 工作温度:-40°C ~ 150°C（TJ） 安装类型:表面贴装 封装/外壳:16-TSSOP（0.173"，4.40mm 宽）裸焊盘 供应商器件封装:16-eTSSOP 标准包装:1 |
发布紧急采购，3分钟左右您将得到回复。