- 您现在的位置：买卖IC网 > PDF目录15089 > NCP1450ASN50T1 (ON Semiconductor)IC REG CTRLR BST PWM VM 5TSOP PDF资料下载
参数资料
| 型号： | NCP1450ASN50T1 |
| 厂商： | ON Semiconductor |
| 文件页数： | 18/22页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BST PWM VM 5TSOP |
| 产品变化通告： | LTB Notification 03/Jan/2008 |
| 标准包装： | 1 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 216kHz |
| 占空比： | 90% |
| 电源电压： | 0.6 V ~ 5.5 V |
| 降压： | 无 |
| 升压： | 是 |
| 回扫： | 无 |
| 反相： | 无 |
| 倍增器： | 无 |
| 除法器： | 无 |
| Cuk： | 无 |
| 隔离： | 无 |
| 工作温度： | -40°C ~ 85°C |
| 封装/外壳： | 6-TSOP（0.059"，1.50mm 宽）5 引线 |
| 包装： | 剪切带 (CT) |
| 其它名称： | NCP1450ASN50TOSCT |
NCP1450A
APPLICATION CIRCUIT INFORMATION
Step?up Converter Design Equations
The NCP1450A PWM step?up DC?DC controller is
designed to operate in continuous conduction mode and can
Calculate the maximum inductance value which can
generate the desired current output and the preferred delta
inductor current to average inductor current ratio:
be defined by the following equations. External components
values can be calculated from these equations, however, the
optimized value should obtained through experimental
L v
(3.3 V ) 0.3 V * 2.4 V)(1 * 0.364)2
180000 Hz 1A 0.2
+ 13.5 m H
results.
Determine the average inductor current and peak inductor
current:
v OUT
IL +
+ 1.57 A
IPK + 1.57A (1 ) 0.2 ) + 1.73A
Calculation
D
I L
L
Equation
V ) VD * VIN
VOUT ) VD * VS
IO
(1 * D)
(VOUT ) VD * VIN)(1 * D)2
f IO DIR
1
1 * 0.364
2
Therefore, a 12 m H inductor with saturation current larger
than 1.73 A can be selected as the initial trial.
Calculate the delta charge stored in the output capacitor
during the charging up period in each switching cycle:
IL (1 ) DIR )
I PK
D Q
2
( IL * IO)(1 * D)
D Q +
(1.57A * 1A)(1 * 0.364)
18000Hz
+ 2.01 m C
f
Determine the output capacitance value for the desired
[
COUT u
+ 138.6 m F
NOTES:
D ? On?time duty cycle
I L ? Average inductor current
V PP D Q
COUT
) ( IL * IO) ESR
output ripple voltage:
Assume the ESR of the output capacitor is 0.15 W ,
2.01 m C
100mV * (1.57A * 1A) 0.15 W
I PK ? Peak inductor current
DIR ? Delta inductor current to average inductor current ratio
I O ? Desired dc output current
V IN ? Nominal operating dc input voltage
V OUT ? Desired dc output voltage
V D ? Diode forward voltage
V S ? Saturation voltage of the external transistor switch
Therefore, a Tantalum capacitor with value of 150 m F to
220 m F and ESR of 0.15 W can be used as the output
capacitor. However, according to experimental result,
220 m F output capacitor gives better overall operational
stability and smaller ripple voltage.
D Q
ESR
? Charge stores in the C OUT during charging up
? Equivalent series resistance of the output capacitor
External Component Selection
Design Example
It is supposed that a step?up DC?DC controller with 3.3 V
output delivering a maximum 1000 mA output current with
100 mV output ripple voltage powering from a 2.4 V input
is to be designed.
Design parameters:
V IN = 2.4 V
V OUT = 3.3 V
I O = 1.0 A
V pp = 100 mV
f = 180 kHZ
DIR = 0.2 (typical for small output ripple voltage)
Assume the diode forward voltage and the transistor
saturation voltage are both 0.3 V. Determine the maximum
steady state duty cycle at V IN = 2.4 V:
Inductor Selection
The NCP1450A is designed to work well with a 6.8 to
12 m H inductors in most applications 10 m H is a sufficiently
low value to allow the use of a small surface mount coil, but
large enough to maintain low ripple. Lower inductance
values supply higher output current, but also increase the
ripple and reduce efficiency.
Higher inductor values reduce ripple and improve
efficiency, but also limit output current.
The inductor should have small DCR, usually less than
1 W , to minimize loss. It is necessary to choose an inductor
with a saturation current greater than the peak current which
the inductor will encounter in the application.
D +
3.3 V ) 0.3 V * 2.4 V
3.3 V ) 0.3 V * 0.3 V
+ 0.364
http://onsemi.com
18
相关PDF资料 |
PDF描述 |
|---|---|
| SD3110-6R8-R | INDUCT PWR LOW PROFILE 6.8UH SMD |
| EMM12DSAS | CONN EDGECARD 24POS R/A .156 SLD |
| SD3110-680-R | INDUCTR PWR LOW PROFILE 68UH SMD |
| SLPX333M016E7P3 | CAP ALUM 33000UF 16V 20% SNAP |
| ESM24DRXS | CONN EDGECARD 48POS DIP .156 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| NCP1450ASN50T1G | 功能描述:直流/直流开关转换器 5V 1A Boost DC-DC PWM RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| NCP1450ASN50T1G | 制造商:ON Semiconductor 功能描述:Power Supply IC |
| NCP1500DMR2 | 功能描述:直流/直流开关转换器 Dual Mode PWM RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| NCP1500DMR2G | 功能描述:直流/直流开关转换器 Dual Mode PWM Linear Buck RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| NCP1501DMR2 | 功能描述:直流/直流开关转换器 Dual Mode Buck w/LDO RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
发布紧急采购，3分钟左右您将得到回复。