参数资料
型号: IR3651STRPBF
厂商: International Rectifier
文件页数: 16/19页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM VM 14-SOIC
标准包装: 2,500
PWM 型: 电压模式
输出数: 1
频率 - 最大: 460kHz
占空比: 80%
电源电压: 4.5 V ~ 13.2 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: 0°C ~ 125°C
封装/外壳: 14-SOIC(0.154",3.90mm 宽)
包装: 带卷 (TR)
配用: IRDC3651-ND - KIT REF DESIGN SYNCH BUCK REG
IR3651SPBF
To cancel one of the LC filter poles, place the
zero before the LC filter resonant frequency pole:
Z IN
V O
C 3
F z = 0 . 75 *
F z = 75 % F LC
1
2 π L o * C o
- -(16)
C 7
R 10
R 8
R 3
C 4
Z f
Using equations (15) and (16) to calculate C 4 .
One more capacitor is sometimes added in
R 9
Fb
E/A
Comp
Ve
parallel with C 4 and R 3 . This introduces one more
pole which is mainly used to suppress the
switching noise.
The additional pole is given by:
Gain(dB)
H(s) dB
V REF
2 π * R 3 * 4
F P =
1
C * C POLE
C 4 + C POLE
F Z 1
F Z 2
F P 2
F P 3
Frequency
The pole sets to one half of switching frequency
which results in the capacitor C POLE :
Fig.15: Compensation network with local
feedback and its asymptotic gain plot
C POLE =
For F P <<
1
π * R 3 * F s ?
F s
2
1
C 4
?
1
π * R 3 * F s
As known, transconductance amplifier has high
impedance (current source) output, therefore,
consideration should be taken when loading the
error amplifier output. It may exceed its
source/sink output current capability, so that the
For a general solution for unconditionally stability
for any type of output capacitors, in a wide range
of ESR values we should implement local
feedback with a compensation network (typeIII).
The typically used compensation network for
voltage-mode controller is shown in figure 15.
amplifier will not be able to swing its output
voltage over the necessary range.
The compensation network has three poles and
two zeros and they are expressed as follows:
F P 1 = 0
V e 1 ? g m Z f
2 π * R 3 ? ? 4
? C * C 3 ?
C 4 + C 3 ? ?
In such configuration, the transfer function is
given by:
=
V o 1 + g m Z IN
The error amplifier gain is independent of the
F P 2 =
F P 3 =
1
2 π * R 10 * C 7
1
?
?
?
1
2 π * R 3 * C 3
transconductance under the following condition:
g m * Z f >> 1 and g m * Z in >> 1 - -(17)
By replacing Z in and Z f according to figure 15, the
F z 1 =
F z 2 =
1
2 π * R 3 * C 4
1
2 π * C 7 * ( R 8 + R 10 )
?
1
2 π * C 7 * R 8
transformer function can be expressed as:
Cross over frequency is expressed as:
1 ( 1 + sR 3 C 4 ) * 1 + sC 7 ( R 8 + R 10 ) ]
sR 8 ( C 4 + C 3 ) ?
? C 4 * C 3 ? ?
? 1 + sR 3 ? ? ? * ( 1 + sR 10 C 7 )
V in 1
V osc 2 π * L o * C o
H ( s ) =
*
? ? C 4 + C 3 ? ?
F o = R 3 * C 7 *
*
06/08/2011
16
相关PDF资料
PDF描述
IR3710MTRPBF IC REG CTRLR BUCK PWM 16-MLPQ
IR3720MTRPBF IC POWER SUPPLY MONITOR 10-DFN
IR3721MTRPBF IC POWER SUPPLY MONITOR 10-DFN
IR3725MTRPBF IC PWR MONITOR INPUT 12-DFN
IR3800AMTRPBF IC REG BUCK SYNC ADJ 14A 15QFN
相关代理商/技术参数
参数描述
IR3651STRPBF-CUT TAPE 制造商:IR 功能描述:IR3651SPbF Series 13.2 V 7 mA High Voltage Synchronous PWM Buck Controller
IR367319 制造商:Thomas & Betts 功能描述:CONNECTOR
IR3702 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog IC
IR3702N 制造商:未知厂家 制造商全称:未知厂家 功能描述:Analog IC
IR370BGD 制造商:未知厂家 制造商全称:未知厂家 功能描述: