- 您现在的位置：买卖IC网 > PDF目录20807 > FL7701M (Fairchild Semiconductor)IC LED DRIVER PFC BUCK 8-SOIC PDF资料下载
参数资料
| 型号： | FL7701M |
| 厂商： | Fairchild Semiconductor |
| 文件页数： | 7/13页 |
| 文件大小： | 0K |
| 描述： | IC LED DRIVER PFC BUCK 8-SOIC |
| 标准包装： | 95 |
| 拓扑： | PWM，降压（降压） |
| 输出数： | 1 |
| 内部驱动器： | 无 |
| 类型 - 主要： | 通用 |
| 频率： | 可调节/可选择 |
| 电源电压： | 9 V ~ 20 V |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 供应商设备封装： | 8-SO |
| 包装： | 管件 |
| 工作温度： | -40°C ~ 125°C |
n ? V f ? ( 1 ? D min )
L m ? [ H ]
4. Dimming Function
The FL7701 uses the ADIM pin for analog or 0 V to
10 V dimming by using a resistive divider. The peak
voltage of internal reference, which is DAC_OUT signal
in Figure 5, is changed by the V ADIM level, as shown in
In DCM Mode, inductance is:
f s ? ? i rip
(2)
Figure 7, and has different peak level according to the
operating mode.
If the peak current is fixed at 350 mApk, the formula for
the peak current is:
V DAC _ OUT
I LED ( ave . peak ) ? ? i con ?
? i rip
2
[A]
(3)
0 .5 V
0.365V
AC mode
DC mode
In FL7701, the LED RMS current determines the
inductance parameter. To drive for CCM Mode, define
LED RMS current first, as:
I LED ( rms ) ?
I LED ( ave . peak ) [A]
2
(4)
Substituting
Equation
(2)
for
Equation
(4),
the
0. 5 V
3 . 5V
V ADIM
inductance of inductor is obtained.
Figure 7. V ADIM vs. V DAC_OUT(peak)
V IN
5. Inductor Design
4 Π
The FL7701 prefixed internal duty ratio range is below
Π
2 Π
3 Π
t
50%, or around 400 ns, from timing point of view. The
range is dependent on the input voltage and LED
numbers in its string.
Minimum duty is calculated as:
V bridge
ZCD
Input Voltage
Peak
Bridge Diode
Output Voltage
V dd Charging
Voltage
t
D min ?
n ? V f
? ? V in (max)
(1)
DAC
t
t
where:
V LED
η is efficiency of system;
V IN(max) is maximum input voltage;
V drain
Input Voltage
Peak
t
V f is forward drop voltage of LED; and
n is LED number in series connection.
t
Current Limit
Average
I LED
Input Voltage
Peak
t
LED Current
I FRD
t
Current peak at LED average
t on t off
D min 1-D min
(a) DCM Mode
Current peak at LED current
maximum point (I LED(peak) )
Average
I MOSFET
I input
t
current maximum point
(I LED(ave.peak) )
LED Current (I LED(ave) )
t
DCM
? i
0.5 ? i
DCM
T/2 = 1/(Input Frequency * 2)
0.5 ? i
CCM
Current min at LED current
maximum point (I LED(min) )
T = 1/Input Ferquency
Figure 9. Typical Performance Characteristics
D min
t on t off
1-D min
(b) CCM Mode
Figure 8. DCM and CCM Operation
? 2011 Fairchild Semiconductor Corporation
FL7701 ? Rev. 1.0.4
7
www.fairchildsemi.com
相关PDF资料 |
PDF描述 |
|---|---|
| REC3-123.3SRW/H6/C/M | CONV DC/DC 3W 9-18VIN 3.3VOUT |
| TH3C475K035C1300 | CAP TANT 4.7UF 35V 10% 2312 |
| TH3C475K025C1600 | CAP TANT 4.7UF 25V 10% 2312 |
| P51-300-S-C-D-4.5OVP-000-000 | SENSOR 300PSI M12-1.5 6G .5-4.5V |
| P51-200-S-AD-M12-4.5V-000-000 | SENSOR 200PSI 7/16-20 UNF 4.5V |
相关代理商/技术参数 |
参数描述 |
|---|---|
| FL7701MX | 功能描述:LED照明驱动器 Smart Non-isolated PFC Buck LED Driver 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 |
| FL7730 | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| FL7730MY | 功能描述:LED照明驱动器 Single Stage PFC PSR Off-line LED Driver 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 |
| FL7730MY_F116 | 功能描述:LED照明驱动器 Single Stage PFC PSR Off-line LED Driver 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 |
| FL7732 | 制造商:FAIRCHILD 制造商全称:Fairchild Semiconductor 功能描述:Single-Stage PFC Primary-Side-Regulation Offline LED Driver |
发布紧急采购，3分钟左右您将得到回复。