收藏本站
S P 7 6 0 0
2 A 2 9 V N o n - S y n c . B u c k H i g h P o w e r L E D D r i v e r
DESIGN EXAMPLE
Schottky current rating I F
Design a drive circuit for a 1.5A LED with a
12V input voltage. Nominal LED voltage is
3.6V.
I F ≥ 1 ?
3 . 3 V
12 V
× 1 . 5 A = 1 . 3 A
Resistor RFB calculation
Voltage rating should be 30V. B340A rated at
30V/3A or equivalent can be used for its
RFB =
0.2 V
1 . 5 A
= 0 . 13 Ω
ample current rating and low forward voltage.
Rs calculation
A standard value of 0.12ohm 0805 is selected.
Inductor L1 calculation
Rs =
0.35 V ? (1.5 × 1.05 × 2.25 A × 0.095 Ω )
33 μ A
= 424 Ω
L 1 =
3 . 6 V × ( 12 V ? 3 . 6 V )
12 V × 1 . 3 MHz × 0 . 45 A
= 4 . 3 μ H
Use standard resistor value for Rs of 470 ? .
An inductor of 4.7uH, rated at 3A RMS and 3A
I SAT is selected.
Input capacitor
A 10μF C IN (C1) is needed (refer to table 1).
From Equ.4, the ripple current rating of C IN is
a fraction of 1.5A. A 10uF/16V ceramic
capacitor easily meets this requirement and
offers low ESR and ESL.
LAYOUT CONSIDERATION
i) Place the bypass capacitors C4 and C5 as
close as possible to the 7600 IC. See figure 5
for details.
ii) Create a pad under the IC that connects the
power pad (pin 9) to the inductor. Duplicate
this pad through the pcb layers if present, and
on the bottom side of the PCB. Use multiple
vias to connect these layers to aid in heat
dissipation. Do not oversize this pad - since
the LX node is subjected to very high dv/dt
voltages, the stray capacitance formed
between these islands and the surrounding
circuitry will tend to couple switching noise
iii) Connect the Schottky diode cathode as
close as possible to the LX node and inductor
input side. Connect the anode to a large
diameter trace or a copper area that connects
the input ground to the output ground.
iv) The output capacitor, if used, should be
placed close to the load. Use short wide
Fig. 18: Circuit for design example
copper regions to connect output capacitors to
load to minimize inductance and resistances.
v) Keep other sensitive circuits and traces
away from the LX node in particular and away
from the power supply completely if possible.
For more detail on the SP7600 layout see the
SP7600EB Evaluation Board Manual available
on our web site. Each layer is shown in detail
as well as a complete bill of materials.
Fig. 19: SP7600 Eval Board
Component Side Lay
? 2009 Exar Corporation
11/13
Rev. 2.0.0
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
SPB2 PANEL SWING KIT
SPIKECUBE SURGE SUPPRESSR 1OUT DIRECT PLUG
SPIKESTIK SURGE SUPPRESSOR SPIKE STIK 6OUT
SPS-615-HG SURGE SUPP 6OUT 15'CORD HOSP GRD
SR202 SHELF FIXED 4-POST HEAVY DUTY
SR204 SHELF FIXED 2U CANTILEVER
SR205 SHELF SLIDING 4-POST 1U
SR206 SHELF SLIDING 4-POST 2U
相关代理商/技术参数
SP7600EN2-L/TR 功能描述:LED照明驱动器 2A 29V NON-SYNC BUCK HIGH PWR RoHS:否 制造商:STMicroelectronics 输入电压:11.5 V to 23 V 工作频率: 最大电源电流:1.7 mA 输出电流: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:SO-16N
SP7601 制造商:EXAR 制造商全称:EXAR 功能描述:29V High Voltage LED Driver
SP7601_EB 制造商:EXAR 制造商全称:EXAR 功能描述:29V High Voltage LED Driver
SP7601EB 功能描述:LED 照明开发工具 Eval Board for SP7601 Series RoHS:否 制造商:Fairchild Semiconductor 产品:Evaluation Kits 用于:FL7732 核心: 电源电压:120V 系列: 封装:
SP7601EK1-L 功能描述:LED照明驱动器 High Curr DC-to-DC Buck LED Drvr 1.2MHz RoHS:否 制造商:STMicroelectronics 输入电压:11.5 V to 23 V 工作频率: 最大电源电流:1.7 mA 输出电流: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:SO-16N
SP7601EK1-L/TR 功能描述:LED照明驱动器 RoHS:否 制造商:STMicroelectronics 输入电压:11.5 V to 23 V 工作频率: 最大电源电流:1.7 mA 输出电流: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:SO-16N
SP7606 制造商:EXAR 制造商全称:EXAR 功能描述:Wide Input Voltage Boost Controller
SP7606ER-L 制造商:EXAR 制造商全称:EXAR 功能描述:Wide Input Voltage Boost Controller