- 您现在的位置：买卖IC网 > Datasheet目录307 > A8514KLPTR-T (Allegro Microsystems Inc)IC LED DVR WHT 4X80MA 16-ETSSOP Datasheet资料下载
参数资料
| 型号： | A8514KLPTR-T |
| 厂商： | Allegro Microsystems Inc |
| 文件页数： | 36/42页 |
| 文件大小： | 0K |
| 描述： | IC LED DVR WHT 4X80MA 16-ETSSOP |
| 标准包装： | 8,000 |
| 拓扑： | PWM，SEPIC，升压（升压） |
| 输出数： | 4 |
| 内部驱动器： | 是 |
| 类型 - 主要： | 车载，背光 |
| 类型 - 次要： | 白色 LED |
| 频率： | 580kHz ~ 2MHz |
| 电源电压： | 5 V ~ 40 V |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 20-TSSOP（0.173"，4.40mm 宽）裸露焊盘 |
| 供应商设备封装： | 20-TSSOP-EP |
| 包装： | 带卷 (TR) |
| 工作温度： | -40°C ~ 125°C |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页当前第36页第37页第38页第39页第40页第41页第42页
A8514
Wide Input Voltage Range, High Efficiency
Fault Tolerant LED Driver
Appendix A. Feed Back Loop Components Calculation
for Peak Current Control Boost Converter Used in LED Drivers Applications
This appendix provides an examination of the factors involved
in calculating the transfer function of a peak current controlled
A P , DC gain
The DC gain is defined as follows:
boost converter, an output to control transfer function, and rec-
ommendations for stabilizing the feedback loop closed system.
An example of a complete small signal model of a peak-current-
A P =
1 – D (nom)
R I
×
R S × R EQ
R S + R D + R EQ
(A-3)
1+
× 1 –
(A-1)
2× × f × j 2× × f × j (2 × × f × j ) 2
ω S2
Q D × ω S
ω P
mode boost converter is shown in figureA-2.TheA8514 is an
example of a boost converter that drives 4 LED strings with
10 LEDs in each string.
Power Stage Transfer Function
Using a frequency-based model, the transfer function (control to
output) of boost power stage peak-current control is given by the
following equation:
2× × f × j 2× × f × j
ω Z ω RHP
T P (f ) = A P ×
1+ × 1 + –
A P is the DC gain,
ω Z is the angular frequency of the output capacitor
ESR zero, f Z ,
ω RHP is the angular frequency of the right-half plane
zero, f RHP ,
ω P is the angular frequency of the output load pole, f P ,
Q D is the inductor peak current sampling double pole quality or
damping factor, and
ω S is the double-pole angular frequency oscillation .
Figure A-1 shows the plot of the power stage logarithmic transfer
function as gain, G P(f) , versus frequency. with G P(f) given by:
G P (f) = 20 × log( | T P (f) | ) (A-2)
where
? D is the PWM duty cycle, calculated as:
D (nom) = ( V OUT – V IN (nom)) / V OUT (A-4)
where
V OUT = N L × V f + V REG + V D (A-5)
and
N L is the quantity of LEDs per string,
V f is the nominal forward voltage drop for each
LED diode,
V REG is the current sink regulated voltage for each
LED string, and
V D is the Schottky diode forward voltage drop.
? R I is the current sense resistor, which is connected in series
with the boost power switch,
? R S is the LED sink pin sense resistor, which is usually located
inside the IC and can be calculated from the following
equation:
R S = V REG / I LED (A-6)
where I LED is the current through one LED string,
0
The next sections define the components of T P (f).
–100
10
100
1 × 10 3
1 × 10 4
1 × 10 5
1 × 10 6
1 × 10 7
1 × 10 8
Frequency (Hz)
Figure A-1. Plot of power stage transfer function versus frequency
A8514-APPXA
Allegro MicroSystems, LLC
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com
A-1
相关PDF资料 |
PDF描述 |
|---|---|
| A8515GLPTR-T | IC LED DVR WHT/RGB BKLGT 16TSSOP |
| A8516ELPTR-T | IC LED DVR BACKLIGHT MON 24TSSOP |
| A8740EEETR-T | IC PHOTOFLASH CAP CHARGER 8DFN |
| AC162049-2 | MOD PROGR UNIV MPLAB ICD2 ICD3 |
| AC162049 | MODULE SOCKET FOR ICD2 DIP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| A8515 | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:The A8515 is a multi-output white LED (WLED) driver for LCD backlighting in consumer and industrial displays. |
| A8515GLPTR-T | 功能描述:IC LED DVR WHT/RGB BKLGT 16TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- 恒定电流:- 恒定电压:- 拓扑:升压（升压），切换式电容器（充电泵） 输出数:1 内部驱动器:是 类型 - 主要:背光 类型 - 次要:白色 LED 频率:625kHz ~ 875kHz 电源电压:2.7 V ~ 5.3 V 输出电压:5V 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽） 供应商设备封装:10-µMAX 包装:带卷 (TR) 工作温度:-40°C ~ 85°C |
| A8516 | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:The A8516 is a multi-output WLED/RGB driver for backlighting LCD monitors and televisions. |
| A85169-000 | 制造商:TE Connectivity 功能描述:MPCB-20.0-0-E563 - Cable Rools/Shrink Tubing |
| A8516ELBTR-T | 制造商:ALLEGRO 制造商全称:Allegro MicroSystems 功能描述:The A8516 is a multi-output WLED/RGB driver for backlighting LCD monitors and televisions. |
发布紧急采购，3分钟左右您将得到回复。