参数资料
型号: NCP1547DG
厂商: ON Semiconductor
文件页数: 11/15页
文件大小: 0K
描述: IC REG BUCK ADJ 1.5A 8SOIC
标准包装: 98
类型: 降压(降压)
输出类型: 可调式
输出数: 1
输出电压: 1.5 V ~ 24 V
输入电压: 4.5 V ~ 40 V
PWM 型: 混合物
频率 - 开关: 340kHz
电流 - 输出: 1.5A
同步整流器:
工作温度: 0°C ~ 70°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-SOICN
NCP1547
IP * P + O
) ) ESL( IN
) + ESL( IN )
VRIPPLE(ESL) + ESL(
them for some low cost designs. Electrolytic capacitors are
physically large, and not used in applications where the size,
and especially height is the major concern.
Ceramic capacitors are now available in values over 10 m F.
Since the ceramic capacitor has low ESR and ESL, a single
ceramic capacitor can be adequate for both low frequency
and high frequency noises. The disadvantage of ceramic
capacitors are their high cost. Solid tantalum capacitors can
have low ESR and small size. However, the reliability of the
tantalum capacitor is always a concern in the application
where the capacitor may experience surge current.
Output Capacitor
In a buck converter, the requirements on the output
capacitor are not as critical as those on the input capacitor.
The current to the output capacitor comes from the inductor
and thus is triangular. In most applications, this makes the
RMS ripple current not an issue in selecting output
capacitors.
Figure 15. The Output Voltage Ripple Using Two 10 m F
Ceramic Capacitors in Parallel
Figure 17. The Output Voltage Ripple Using
One 100 m F OS ? CON
The output ripple voltage is the sum of a triangular wave
caused by ripple current flowing through ESR, and a square
wave due to ESL. Capacitive reactance is assumed to be
small compared to ESR and ESL. The peak to peak ripple
current of the inductor is:
V (VIN * VO)
(VIN)(L)(fS)
V RIPPLE(ESR) , the output ripple due to the ESR, is equal
to the product of I P ? P and ESR. The voltage developed
across the ESL is proportional to the di/dt of the output
capacitor. It is realized that the di/dt of the output capacitor
is the same as the di/dt of the inductor current. Therefore,
when the switch turns on, the di/dt is equal to (V IN ? V O )/L,
and it becomes V O /L when the switch turns off. The total
ripple voltage induced by ESL can then be derived from
VO       V * VO V
L L L
The total output ripple is the sum of the V RIPPLE(ESR) and
V RIPPLE(ESL) .
Figure 16. The Output Voltage Ripple Using One
100 m F POSCAP Capacitor
Figure 18. The Output Voltage Ripple Using
One 100 m F Tantalum Capacitor
http://onsemi.com
11
相关PDF资料
PDF描述
NCP1550SN33T1G IC REG CTRLR BUCK PWM VM 5TSOP
NCP1560HDR2 IC REG CTRLR FLYBACK PWM 16-SOIC
NCP1562BDR2G IC REG CTRLR PWM VM 16-SOIC
NCP1571DG IC REG CTRLR BUCK PWM 8-SOIC
NCP1573DR2 IC REG CTRLR BUCK PWM 8-SOIC
相关代理商/技术参数
参数描述
NCP1547DR2G 功能描述:直流/直流开关调节器 340 KHZ REGULATOR RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
NCP1547MNR2G 功能描述:直流/直流开关调节器 340 KHZ RoHS:否 制造商:International Rectifier 最大输入电压:21 V 开关频率:1.5 MHz 输出电压:0.5 V to 0.86 V 输出电流:4 A 输出端数量: 最大工作温度: 安装风格:SMD/SMT 封装 / 箱体:PQFN 4 x 5
NCP1550SN18T1 功能描述:直流/直流开关转换器 1.8V 2A Buck PWM/PFM 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
NCP1550SN18T1G 功能描述:直流/直流开关转换器 1.8V 2A Buck PWM/PFM w/Enable Soft Start 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
NCP1550SN19T1 功能描述:直流/直流开关转换器 1.8V 2A Buck PWM/PFM 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