- 您现在的位置：买卖IC网 > PDF目录14733 > IR3840MTR1PBF (International Rectifier)IC REG BUCK SYNC ADJ 12A 15QFN PDF资料下载
参数资料
| 型号： | IR3840MTR1PBF |
| 厂商： | International Rectifier |
| 文件页数： | 19/32页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 12A 15QFN |
| 产品培训模块： | SupIRBuck? Family and POL Design Tools Overview |
| 标准包装： | 1 |
| 系列： | SupIRBuck™ |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 0.7 V ~ 14.4 V |
| 输入电压： | 1.5 V ~ 16 V |
| PWM 型： | 电压模式 |
| 频率 - 开关： | 225kHz ~ 1.65MHz |
| 电流 - 输出： | 12A |
| 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： | 15-PowerVQFN |
| 包装： | 标准包装 |
| 供应商设备封装： | PQFN（5x6） |
| 产品目录页面： | 1384 (CN2011-ZH PDF) |
| 其它名称： | IR3840MTR1PBFDKR |
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页当前第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页
IR3840MPbF
Output Capacitor Selection
The voltage ripple and transient requirements
determine the output capacitors type and values.
The criteria is normally based on the value of the
Effective Series Resistance (ESR). However the
actual capacitance value and the Equivalent Series
The output LC filter introduces a double pole,
–40dB/decade gain slope above its corner
resonant frequency, and a total phase lag of 180 o
(see figure 13). The resonant frequency of the LC
filter is expressed as follows:
Inductance (ESL) are other contributing
components. These components can be described
as
F LC =
1
2 ? π L o ? C o
.......... .......... .......... .. (16)
Δ V o = Δ V o ( ESR ) + Δ V o ( ESL ) + Δ V o ( C )
Δ V o ( ESR ) = Δ I L * ESR
Figure 13 shows gain and phase of the LC filter.
Since we already have 180 o phase shift from the
output filter alone, the system runs the risk of
being unstable.
Δ V o ( ESL ) = ?? in
?? * ESL
? V ? V o ?
? L ?
Gain
Phase
Δ V o ( C ) =
Δ I L
8 * C o * F s
.......... .......... ..... (15)
0 dB
-40dB/decade
0 0
Δ V o = Output
voltage
ripple
Δ I L = Inductor ripple current
Since the output capacitor has a major role in the
F LC Frequency
-180 0
F LC Frequency
overall performance of the converter and
determines the result of transient response,
selection of the capacitor is critical. The IR3840
can perform well with all types of capacitors.
As a rule, the capacitor must have low enough
ESR to meet output ripple and load transient
requirements.
The goal for this design is to meet the voltage
ripple requirement in the smallest possible
capacitor size. Therefore it is advisable to select
ceramic capacitors due to their low ESR and ESL
and small size. Six of the Panasonic ECJ-
2FB0J226ML (22uF, 6.3V, 3mOhm) capacitors is
a good choice.
Feedback Compensation
The IR3840 is a voltage mode controller. The
control loop is a single voltage feedback path
including error amplifier and error comparator. To
achieve fast transient response and accurate
output regulation, a compensation circuit is
Fig. 13. Gain and Phase of LC filter
The IR3840 uses a voltage-type error amplifier
with high-gain (110dB) and wide-bandwidth. The
output of the amplifier is available for DC gain
control and AC phase compensation.
The error amplifier can be compensated either in
type II or type III compensation.
Local feedback with Type II compensation is
shown in Fig. 14.
This method requires that the output capacitor
should have enough ESR to satisfy stability
requirements. In general the output capacitor’s
ESR generates a zero typically at 5kHz to 50kHz
which is essential for an acceptable phase
margin.
The ESR zero of the output capacitor is
expressed as follows:
necessary. The goal of the compensation
network is to provide a closed-loop transfer
function with the highest 0 dB crossing frequency
F ESR =
1
2 ? π *ESR*C o
.......... .......... ....... (17)
and adequate phase margin (greater than 45 o ).
06/18/09
19
相关PDF资料 |
PDF描述 |
|---|---|
| SLP223M035H4P3 | CAP ALUM 22000UF 35V 20% SNAP |
| VI-22N-EY-F2 | CONVERTER MOD DC/DC 18.5V 50W |
| LLS2C152MELA | CAP ALUM 1500UF 160V 20% SNAP |
| EBC36DRES-S734 | CONN EDGECARD 72POS .100 EYELET |
| IHLP2525CZER4R7M07 | INDUCTOR POWER 4.7UH 5.5A SMD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| IR3840MTR1PBF | 制造商:International Rectifier 功能描述:IC DC/DC SUPIRBUCK 12A 15QFN |
| IR3840MTRPBF | 功能描述:直流/直流开关调节器 12A SupIRBuck Reg 250-1500kHz, 1.5-16V 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 |
| IR3840WMPBF | 制造商:IRF 制造商全称:International Rectifier 功能描述:HIGHLY EFFICIENT INTEGRATED 12A SYNCHRONOUS BUCK REGULATOR |
| IR3840WMPBF_12 | 制造商:IRF 制造商全称:International Rectifier 功能描述:HIGHLY EFFICIENT INTEGRATED 12A SYNCHRONOUS BUCK REGULATOR |
| IR3840WMTR1PBF | 功能描述:直流/直流开关调节器 12A SupIRBuck Reg 250-1500kHz, 1.5-16V 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。