- 您现在的位置：买卖IC网 > PDF目录13854 > LT1376HVCS8 (Linear Technology)IC REG BUCK ADJ 1.5A 8SOIC PDF资料下载
参数资料
| 型号： | LT1376HVCS8 |
| 厂商： | Linear Technology |
| 文件页数： | 25/28页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK ADJ 1.5A 8SOIC |
| 标准包装： | 100 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 2.42 V ~ 21.5 V |
| 输入电压： | 5 V ~ 25 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 500kHz |
| 电流 - 输出： | 1.5A |
| 同步整流器： | 无 |
| 工作温度： | 0°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 8-SOIC（0.154"，3.90mm 宽） |
| 包装： | 管件 |
| 供应商设备封装： | 8-SOIC |
| 产品目录页面： | 1327 (CN2011-ZH PDF) |
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页当前第25页第26页第27页第28页
LT1375/LT1376
APPLICATIO N S I N FOR M ATIO N
INDUCTOR VALUE
Minimum inductor discontinuous mode:
( f )( I )
Unlike buck converters, positive-to-negative converters
cannot use large inductor values to reduce output ripple
voltage. At 500kHz, values larger than 25 μ H make almost
no change in output ripple. The graph in Figure 19 shows
peak-to-peak output ripple voltage for a 5V to – 5V con-
L MIN =
2 ( V OUT )( I OUT )
2
P
verter versus inductor value. The criteria for choosing the
Minimum inductor continuous mode:
( )( )
V V
? I ? I ? 1 +
? P OUT ?
?
) ? ? ? ?
? ?
inductoristhereforetypicallybasedonensuringthatpeak
switch current rating is not exceeded. This gives the
lowest value of inductance that can be used, but in some
cases (lower output load currents) it may give a value that
creates unnecessarily high output ripple voltage. A com-
promise value is often chosen that reduces output ripple.
L MIN =
2 ( f ) ( V IN + V OUT
)
? ?
IN OUT
?
(
V OUT + V F
V IN
? ?
As you can see from the graph, large inductors will not
give arbitrarily low ripple, but small inductors can give
high ripple.
150
For the example above, with maximum load current of
0.25A:
( ) ( ) . 1 5
120
90
5V TO –5V CONVERTER
OUTPUT CAPACITOR
ESR = 0.1 ?
I CONT =
2 2
5
4 ( 5 + 5 ) ( 5 + 5 + 0 . 5 )
= 0 . 37 A
I LOAD = 0.25A
60
I LOAD = 0.1A
This says that discontinuous mode can be used and the
minimum inductor needed is found from:
( )( )
? ( )
? 500 ? 10 ? 1 . 5
3
30
0
0
5
10 15
INDUCTOR SIZE ( μ H)
20
25
L MIN =
?
2 5 0 . 25
2
= 2 . 2 μ H
1375/76 F19
Figure 19. Ripple Voltage on Positive-to-Negative Converter
The difficulty in calculating the minimum inductor size
needed is that you must first know whether the switcher
will be in continuous or discontinuous mode at the critical
point where switch current is 1.5A. The first step is to use
the following formula to calculate the load current where
the switcher must use continuous mode. If your load
current is less than this, use the discontinuous mode
formula to calculate minimum inductor needed. If load
current is higher, use the continuous mode formula.
Output current where continuous mode is needed:
In practice, the inductor should be increased by about
30% over the calculated minimum to handle losses and
variations in value. This suggests a minimum inductor of
3 μ H for this application, but looking at the ripple voltage
chart shows that output ripple voltage could be reduced by
a factor of two by using a 15 μ H inductor. There is no rule
of thumb here to make a final decision. If modest ripple is
needed and the larger inductor does the trick, go for it. If
ripple is noncritical use the smaller inductor. If ripple is
extremely critical, a second filter may have to be added in
any case, and the lower value of inductance can be used.
Keep in mind that the output capacitor is the other critical
( ) ( ) I
V
4 ( ) ( V + V
I CONT =
V IN + V OUT IN OUT + V F
IN P
2 2
)
factor in determining output ripple voltage. Ripple shown
on the graph (Figure 19) is with a capacitor ESR of 0.1 ? .
This is reasonable for an AVX type TPS “D” or “E” size
13756fd
25
相关PDF资料 |
PDF描述 |
|---|---|
| 25ML82MEFCTZ8X5 | CAP ALUM 82UF 25V 20% RADIAL |
| GBC60DRXN-S734 | CONN EDGECARD 120PS DIP .100 SLD |
| SC53-471 | INDUCTOR SMD 470UH 0.20A 1KHZ |
| 50ML33MEFC8X7 | CAP ALUM 33UF 50V 20% RADIAL |
| 50ZLJ56M6.3X11 | CAP ALUM 56UF 50V 20% RADIAL |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT1376HVCS8#PBF | 功能描述:IC REG BUCK ADJ 1.5A 8SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:250 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V 输入电压:2.05 V ~ 6 V PWM 型:电压模式 频率 - 开关:2MHz 电流 - 输出:500mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:6-UFDFN 包装:带卷 (TR) 供应商设备封装:6-SON（1.45x1） 产品目录页面:1032 (CN2011-ZH PDF) 其它名称:296-25628-2 |
| LT1376HVCS8#TR | 功能描述:IC REG BUCK ADJ 1.5A 8SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V，1.5V，1.8V，2.5V 输入电压:2.7 V ~ 20 V PWM 型:- 频率 - 开关:- 电流 - 输出:50mA 同步整流器:是 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽）裸露焊盘 包装:带卷 (TR) 供应商设备封装:10-MSOP 裸露焊盘 |
| LT1376HVCS8#TRPBF | 功能描述:IC REG BUCK ADJ 1.5A 8SOIC RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V，1.5V，1.8V，2.5V 输入电压:2.7 V ~ 20 V PWM 型:- 频率 - 开关:- 电流 - 输出:50mA 同步整流器:是 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:10-TFSOP，10-MSOP（0.118"，3.00mm 宽）裸露焊盘 包装:带卷 (TR) 供应商设备封装:10-MSOP 裸露焊盘 |
| LT1376HVCS8PBF | 制造商:Linear Technology 功能描述:DC-DC Converter Step-Down 5-30V SOIC8 |
| LT1376HVIS | 功能描述:IC REG BUCK ADJ 1.5A 16SOIC RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 设计资源:Design Support Tool 标准包装:1 系列:- 类型:升压（升压） 输出类型:固定 输出数:1 输出电压:3V 输入电压:0.75 V ~ 2 V PWM 型:- 频率 - 开关:- 电流 - 输出:100mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-5 细型，TSOT-23-5 包装:剪切带 (CT) 供应商设备封装:TSOT-23-5 其它名称:AS1323-BTTT-30CT |
发布紧急采购，3分钟左右您将得到回复。