- 您现在的位置：买卖IC网 > PDF目录17333 > CS5171BSTGEVB (ON Semiconductor)EVAL BOARD FOR CS5171BST PDF资料下载
参数资料
| 型号： | CS5171BSTGEVB |
| 厂商： | ON Semiconductor |
| 文件页数： | 13/21页 |
| 文件大小： | 0K |
| 描述： | EVAL BOARD FOR CS5171BST |
| 设计资源： | CS5171BSTGEVB Gerber Files |
| 标准包装： | 1 |
| 主要目的： | DC/DC，步升 |
| 输出及类型： | 1，非隔离 |
| 输出电压： | 5V |
| 电流 - 输出： | 400mA |
| 输入电压： | 3.3V |
| 稳压器拓扑结构： | 升压 |
| 频率 - 开关： | 260kHz |
| 板类型： | 完全填充 |
| 已供物品： | 板 |
| 已用 IC / 零件： | CS5171 |
| 其它名称： | CS5171BSTEVBOS CS5171BSTEVBOS-ND CS5171BSTGEVBOS |
CS5171, CS5172, CS5173, CS5174
Magnetic Component Selection
When choosing a magnetic component, one must consider
factors such as peak current, core and ferrite material, output
voltage ripple, EMI, temperature range, physical size and
I IN
I L
cost. In boost circuits, the average inductor current is the
product of output current and voltage gain (V OUT /V CC ),
assuming 100% energy transfer efficiency. In continuous
conduction mode, inductor ripple current is
V CC
+
?
C IN
R ESR
IRIPPLE + CC
V (VOUT * VCC)
(f)(L)(VOUT)
where:
f = 280 kHz for CS5171/2 and 560 kHz for CS5173/4.
The peak inductor current is equal to average current plus
half of the ripple current, which should not cause inductor
saturation. The above equation can also be referenced when
selecting the value of the inductor based on the tolerance of
the ripple current in the circuits. Small ripple current
provides the benefits of small input capacitors and greater
output current capability. A core geometry like a rod or
barrel is prone to generating high magnetic field radiation,
but is relatively cheap and small. Other core geometries,
such as toroids, provide a closed magnetic loop to prevent
EMI.
Input Capacitor Selection
In boost circuits, the inductor becomes part of the input
filter, as shown in Figure 35. In continuous mode, the input
current waveform is triangular and does not contain a large
pulsed current, as shown in Figure 34. This reduces the
requirements imposed on the input capacitor selection.
During continuous conduction mode, the peak to peak
inductor ripple current is given in the previous section. As
we can see from Figure 34, the product of the inductor
current ripple and the input capacitor ’s effective series
resistance (ESR) determine the V CC ripple. In most
applications, input capacitors in the range of 10 m F to 100 m F
with an ESR less than 0.3 W work well up to a full 1.5 A
switch current.
V CC ripple
I IN
I L
Figure 34. Boost Input Voltage and Current
Figure 35. Boost Circuit Effective Input Filter
The situation is different in a flyback circuit. The input
current is discontinuous and a significant pulsed current is
seen by the input capacitors. Therefore, there are two
requirements for capacitors in a flyback regulator: energy
storage and filtering. To maintain a stable voltage supply to
the chip, a storage capacitor larger than 20 m F with low ESR
is required. To reduce the noise generated by the inductor,
insert a 1.0 m F ceramic capacitor between V CC and ground
as close as possible to the chip.
Output Capacitor Selection
V OUT ripple
I L
Figure 36. Typical Output Voltage Ripple
By examining the waveforms shown in Figure 36, we can
see that the output voltage ripple comes from two major
sources, namely capacitor ESR and the
charging/discharging of the output capacitor. In boost
circuits, when the power switch turns off, I L flows into the
output capacitor causing an instant D V = I IN × ESR. At the
same time, current I L ? I OUT charges the capacitor and
increases the output voltage gradually. When the power
switch is turned on, I L is shunted to ground and I OUT
discharges the output capacitor. When the I L ripple is small
enough, I L can be treated as a constant and is equal to input
current I IN .
Ripple Waveforms
http://onsemi.com
13
相关PDF资料 |
PDF描述 |
|---|---|
| HK100568NJ-T | INDUCTOR HI FREQ 68NH 5% 0402 |
| F930G477MNC | CAP TANT 470UF 4V 20% 2917 |
| ASPI-0630HI-1R0M-T15 | INDUCTOR POWER 1.0UH 0630 SMD |
| HK10055N1S-T | INDUCTOR HIFREQ 5.1+/-0.3NH 0402 |
| ISL8204MEVAL1Z | EVAL BOARD 1 FOR ISL8204 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| CS5171ED8 | 功能描述:直流/直流开关调节器 1.5A High Efficiency 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 |
| CS5171ED8G | 功能描述:直流/直流开关调节器 1.5A High Efficiency Boost 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 |
| CS5171EDR8 | 功能描述:直流/直流开关调节器 1.5A High Efficiency 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 |
| CS5171EDR8G | 功能描述:直流/直流开关调节器 1.5A High Efficiency Boost 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 |
| CS5171GD8 | 功能描述:直流/直流开关调节器 1.5A High Efficiency 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 |
发布紧急采购，3分钟左右您将得到回复。