- 您現在的位置：買賣IC網 > PDF目錄375723 > FAN5069 (Fairchild Semiconductor Corporation) PWM and LDO Controller Combo PDF資料下載
參數資料
| 型號： | FAN5069 |
| 廠商： | Fairchild Semiconductor Corporation |
| 英文描述： | PWM and LDO Controller Combo |
| 中文描述： | PWM和LDO控制器組合 |
| 文件頁數： | 16/20頁 |
| 文件大小： | 379K |
| 代理商： | FAN5069 |
16
www.fairchildsemi.com
FAN5069 Rev. 1.1.0
F
Poles and Zeros of Plant Transfer Function:
Plant zero frequency =
(EQ. 26)
Plant 1
st
pole frequency =
(EQ. 27)
Plant 2
nd
pole frequency =
(EQ. 28)
Plant 3
rd
pole frequency =
(EQ. 29)
Plant gain (magnitude) response:
(EQ. 30)
Plant phase response:
(EQ. 31)
Choose R1, R
BIAS
to set the output voltage using EQ.5. Choose
the zero cross over frequency F
cross
of the overall loop. Typically
F
cross
should be less than 1/5th of F
sw
. Choose the desired
phase margin. Typically this number should be between 60° to
90°.
Calculate plant gain at F
cross
using EQ.28 by substituting F
cross
in place of f. The gain that the amplifier needs to provide to get
the required cross over is given by
(EQ. 32)
The phase boost required is calculated as given in (EQ. 33).
(EQ. 33)
Where, M is the desired phase margin in degrees and P is the
modulator phase shift in degrees at the time of crossover.
The feedback component values are now calculated as given in
equations below:
(EQ. 34)
(EQ. 35)
(EQ. 36)
(EQ. 37)
(EQ. 38)
(EQ. 39)
Layout Considerations
The switching power converter layout needs careful attention
and is critical to achieving low losses and clean and stable oper-
ation. Below are specific recommendations for a good board
layout:
■
Keep the high current traces and load connections as short
as possible.
■
Use thick copper boards whenever possible to achieve higher
efficiency.
■
Keep the loop area between the SW node, low-side MOS-
FET, inductor and the output capacitor as small as possible.
■
Route high dV/dt signals such as SW node away from the
error amplifier input/output pins. Keep components con-
nected to these pins close to the pins.
■
Place ceramic de-coupling capacitors very close to VCC pin.
■
All input signals are referenced with respect to AGND pin.
Dedicate one layer of the PCB for a GND plane. Use at least
4 layers for the PCB.
■
Minimize GND loops in the layout to avoid EMI related
issues.
■
Use wide traces for the lower gate drive to keep the drive
impedances low.
■
Connect PGND directly to the lower MOSFET source pin.
■
Use wide land areas with appropriate thermal vias to effec-
tively remove heat from the MOSFET’s.
■
Use snubber circuits to minimize high frequency ringing at
the SW nodes.
■
Place the output capacitor for the LDO close to the source of
the LDO MOSFET.
f
z
o
es
-----------------------------------------
=
f
p1
2
π
C
o
R
p
e
R
L
------
+
×
×
×
---------------------------------------------------------
=
f
p2
π
------------
o
L
-------------------
p
L
e
------
+
×
=
f
p3
2
e
R
p
×
×
π
-------------------------
=
G
p
(f)
20
M
0
log
10
1
f
f
p2
---
2
+
1
f
p1
------
+
1
------
+
1
f
p3
------
2
+
×
×
-------------------------------------------------------------------------------------------------------
log
×
+
×
=
G
P
(f)
∠
tan
1
–
f
z
---
tan
1
–
f
f
p1
------
–
tan
1
–
f
f
p2
------
–
tan
1
–
f
f
p3
------
–
–
=
G
AMP
p
cross
)
---------------------------------
=
Phase Boost
M
P
–
90
°
–
=
K
Tan
----------------
45
+
2
=
C1
cross
K
–
AMP
--------------------------------------------------------------------------
=
C2
C1
1
(
)
×
=
C3
2
π
F
cross
K
×
×
×
R3
×
-----------------------------------------------------------------
=
R2
cross
--------------------------------------------------
=
R3
1
–
)
-----------------
=
相關PDF資料 |
PDF描述 |
|---|---|
| FAN5069EMTCX | PWM and LDO Controller Combo |
| FAN5070 | High Performance Programmable Synchronous DC-DC Controller |
| FAN5070M | Voltage-Mode SMPS Controller |
| FAN5071 | High Performance Programmable Synchronous DC-DC Controller for Multi-Voltage Platforms |
| FAN5071M | Analog IC |
相關代理商/技術參數 |
參數描述 |
|---|---|
| FAN5069_06 | 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:PWM and LDO Controller Combo |
| FAN5069_08 | 制造商:FAIRCHILD 制造商全稱:Fairchild Semiconductor 功能描述:PWM and LDO Controller Combo |
| FAN5069B_BAC3116B WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| FAN5069C_BAD3116B WAF | 制造商:Fairchild Semiconductor Corporation 功能描述: |
| FAN5069EMTCX | 功能描述:電流型 PWM 控制器 PWM and ULDO Controller Combo RoHS:否 制造商:Texas Instruments 開關頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
發布緊急采購，3分鐘左右您將得到回復。