收藏本站
LTC3220/LTC3220-1
APPLICATIONS INFORMATION
Flying Capacitor Selection
Warning: Polarized capacitors such as tantalum or
aluminum should never be used for the ?ying capaci-
Table 2 shows a list of ceramic capacitor manufacturers
and how to contact them:
Table 2. Recommended Capacitor Vendors
tors since their voltage can reverse upon start-up of the
LTC3220/LTC3220-1. Ceramic capacitors should always
be used for the ?ying capacitors.
The ?ying capacitors control the strength of the charge
pump. In order to achieve the rated output current it is
AVX
Kemet
Murata
Taiyo Yuden
Vishay
www.avxcorp.com
www.kemet.com
www.murata.com
www.t-yuden.com
www.vishay.com
necessary to have at least 1.6μF of capacitance for each of
the ?ying capacitors. Capacitors of different materials lose
their capacitance with higher temperature and voltage at
different rates. For example, a ceramic capacitor made of
X7R material will retain most of its capacitance from –40°C
to 85°C, whereas a Z5U or Y5V style capacitor will lose
considerable capacitance over that range. Z5U and Y5V
capacitors may also have a very poor voltage coef?cient
causing them to lose 60% or more of their capacitance when
the rated voltage is applied. Therefore, when comparing
different capacitors, it is often more appropriate to compare
the amount of achievable capacitance for a given case size
rather than comparing the speci?ed capacitance value. For
example, over rated voltage and temperature conditions,
a 1μF, 10V, Y5V ceramic capacitor in a 0603 case may not
provide any more capacitance than a 0.22μF, 10V, X7R
available in the same case. The capacitor manufacturer’s
data sheet should be consulted to determine what value
of capacitor is needed to ensure minimum capacitances
at all temperatures and voltages.
Layout Considerations and Noise
The LTC3220/LTC3220-1 have been designed to minimize
EMI. However due to their high switching frequency and the
transient currents produced by the LTC3220/LTC3220-1,
careful board layout is necessary. A true ground plane
and short connections to all capacitors will improve
performance and ensure proper regulation under all
conditions.
The ?ying capacitor pins C1P, C2P, C1M and C2M have
controlled edge rate waveforms. The large dv/dt on these
pins can couple energy capacitively to adjacent PCB runs.
Magnetic ?elds can also be generated if the ?ying capaci-
tors are not close to the LTC3220/LTC3220-1 (i.e., the loop
area is large). To decouple capacitive energy transfer, a
Faraday shield may be used. This is a grounded PCB trace
between the sensitive node and the LTC3220/LTC3220-1
pins. For a high quality AC ground, it should be returned
to a solid ground plane that extends all the way to the
LTC3220/LTC3220-1.
32201fc
17
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
LTC3230EUD#PBF IC LED DRIVR WHITE BCKLGT 20-QFN
LTC3452EUF#TRPBF IC LED DRIVER PHOTO FLASH 20-QFN
LTC3453EUF#TRPBF IC LED DRIVER PHOTO FLASH 16-QFN
LTC3454EDD#TRPBF IC LED DRIVER PHOTO FLASH 10-DFN
LTC3490EDD#PBF IC LED DRIVER PHOTO FLASH 8-DFN
LTC3783EFE#PBF IC LED DRVR PWM CONTROL 16-TSSOP
LV5026MC-AH IC LED DRIVER 1CH HV 10SOIC
LV5213LP-TE-L-E IC LED DVR 3CH CELL PHONE VCT16
相关代理商/技术参数
LTC3220EPF#TRPBF 功能描述:IC LED DRVR QVGA DISPLAY 28UTQFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极，PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3220EPF-1#PBF 功能描述:IC LED DRVR QVGA DISPLAY 28UTQFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极，PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3220EPF-1#TRPBF 功能描述:IC LED DRVR QVGA DISPLAY 28UTQFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极，PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3220EPF-1-PBF 制造商:LINER 制造商全称:Linear Technology 功能描述:360mA Universal 18-Channel LED Driver
LTC3220EPF-1-TRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:360mA Universal 18-Channel LED Driver
LTC3220EPFPBF 制造商:Linear Technology 功能描述:360mA 18-Channel LED Driver LTC3220EPF
LTC3220EPF-PBF 制造商:LINER 制造商全称:Linear Technology 功能描述:360mA Universal 18-Channel LED Driver
LTC3220EPF-TRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:360mA Universal 18-Channel LED Driver