- 您现在的位置：买卖IC网 > PDF目录67757 > LT3484EDCB-0#PBF (LINEAR TECHNOLOGY CORP) SPECIALTY ANALOG CIRCUIT, PDSO6 PDF资料下载
参数资料
| 型号： | LT3484EDCB-0#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 模拟信号调理 |
| 英文描述： | SPECIALTY ANALOG CIRCUIT, PDSO6 |
| 封装： | 2 X 3 MM, LEAD FREE, PLASTIC, MO-229TBD, DFN-6 |
| 文件页数： | 11/12页 |
| 文件大小： | 446K |
| 代理商： | LT3484EDCB-0#PBF |
LT3484-0/LT3484-1/LT3484-2
8
3484012f
voltage as it changes the amplitude of the reflected voltage
from the output to the SW pin. Choose N according to the
following equation:
N
VOUT
=
+ 2
31 5
.
Where: VOUT is the desired output voltage. The number 2
in the numerator is used to include the effect of the voltage
drop across the output diode(s).
Thus for a 320V output, N should be 322/31.5 or 10.2. For
a 300V output, choose N equal to 302/31.5 or 9.6.
The next parameter that needs to be set is the primary
inductance, LPRI. Choose LPRI according to the following
formula:
L
V
NI
PRI
OUT
PK
≥
200 10 9
Where: VOUT is the desired output voltage. N is
the transformer turns ratio. IPK is 1.4 (LT3484-0), 0.7
(LT3484-1), and 1.0 (LT3484-2).
LPRI needs to be equal or larger than this value to ensure
that the LT3484-0/LT3484-1/LT3484-2 has adequate time
to respond to the flyback waveform.
All other parameters need to meet or exceed the recom-
mended limits as shown in Table 1. A particularly impor-
tant parameter is the leakage inductance, LLEAK. When the
power switch of the LT3484-0/LT3484-1/LT3484-2 turns
off, the leakage inductance on the primary of the trans-
former causes a voltage spike to occur on the SW pin. The
height of this spike must not exceed 40V, even though the
absolute maximum rating of the SW Pin is 50V. The 50V
absolute maximum rating is a DC blocking voltage speci-
fication, which assumes that the current in the power NPN
is zero. Figure 3 shows the SW voltage waveform for the
circuit of Figure 6 (LT3484-0). Note that the absolute
maximum rating of the SW pin is not exceeded. Make sure
to check the SW voltage waveform with VOUT near the
target output voltage, as this is the worst case condition
for SW voltage. Figure 4 shows the various limits on the
SW voltage during switch turn off.
It is important not to minimize the leakage inductance to
a very low level. Although this would result in a very low
leakage spike on the SW pin, the parasitic capacitance of
the transformer would become large. This will adversely
affect the charge time of the photoflash circuit.
Linear Technology has worked with several leading mag-
netic component manufacturers to produce pre-designed
flyback transformers for use with the LT3484-0/
LT3484-1/LT3484-2. Table 2 shows the details of several
of these transformers.
APPLICATIO S I FOR ATIO
WU
U
Table 1. Recommended Transformer Parameters
TYPICAL RANGE
PARAMETER
NAME
LT3484-0
LT3484-1
LT3484-2
UNITS
LPRI
Primary Inductance
>5
>10
>7
H
LLEAK
Primary Leakage Inductance
100 to 300
200 to 500
nH
N
Secondary: Primary Turns Ratio
1:8 to 1:12
VISO
Secondary to Primary Isolation Voltage
>500
V
ISAT
Primary Saturation Current
>1.6
>0.8
>1.0
A
RPRI
Primary Winding Resistance
<300
<500
<400
m
RSEC
Secondary Winding Resistance
<40
<80
<60
相关PDF资料 |
PDF描述 |
|---|---|
| LT3484EDCB-2#PBF | SPECIALTY ANALOG CIRCUIT, PDSO6 |
| LT3484EDCB-1#PBF | SPECIALTY ANALOG CIRCUIT, PDSO6 |
| LT3493EDCB#PBF | 2.2 A SWITCHING REGULATOR, 815 kHz SWITCHING FREQ-MAX, PDSO6 |
| LT3493IDCB#PBF | 2.2 A SWITCHING REGULATOR, 815 kHz SWITCHING FREQ-MAX, PDSO6 |
| LT3493EDCB#TRM | 2.2 A SWITCHING REGULATOR, 815 kHz SWITCHING FREQ-MAX, PDSO6 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3484EDCB-1 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Photoflash Capacitor Chargers |
| LT3484EDCB-1#PBF | 制造商:Linear Technology 功能描述:Photo Flash Charger 6-Pin DFN EP |
| LT3484EDCB-1#TR | 功能描述:IC PHOTOFLASH CAP CHARGER 6-DFN RoHS:否 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:- 标准包装:1 系列:- 应用:手持/移动设备 电流 - 电源:- 电源电压:3 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
| LT3484EDCB-1#TRM | 功能描述:IC PHOTOFLASH CAP CHARGER 6-DFN RoHS:否 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:- 标准包装:1 系列:- 应用:手持/移动设备 电流 - 电源:- 电源电压:3 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
| LT3484EDCB-1#TRMPBF | 功能描述:IC PHOTOFLASH CAP CHARGER 6-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 电源管理 - 专用 系列:- 标准包装:1 系列:- 应用:手持/移动设备 电流 - 电源:- 电源电压:3 V ~ 5.5 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:14-WFDFN 裸露焊盘 供应商设备封装:14-LLP-EP（4x4） 包装:Digi-Reel® 配用:LP3905SD-30EV-ND - BOARD EVALUATION LP3905SD-30 其它名称:LP3905SD-30DKR |
发布紧急采购，3分钟左右您将得到回复。