- 您現在的位置：買賣IC網 > PDF目錄384655 > MAX1965 (Maxim Integrated Products, Inc.) Tracking/Sequencing Triple/Quintuple Power-Supply Controllers PDF資料下載
參數資料
| 型號： | MAX1965 |
| 廠商： | Maxim Integrated Products, Inc. |
| 英文描述： | Tracking/Sequencing Triple/Quintuple Power-Supply Controllers |
| 中文描述： | 三/五路電源控制器，提供跟蹤/排序功能 |
| 文件頁數： | 20/30頁 |
| 文件大?。?/td> | 475K |
| 代理商： | MAX1965 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁當前第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁
M
where V
REF
= 1.24V, A
VCS
is the current-sense amplifi-
er
’
s gain (4.9 typ), A
VEA
is the DC gain of the transcon-
ductance error amplifier (2000 typ) set by its DC output
resistance, and V
OUT(NOMINAL)
is the output voltage
set by the feedback resistive-divider (internal or exter-
nal). Since the output voltage is a function of the load
current and load resistance, the total DC loop gain
(A
V(DC)
) is approximately:
The first compensation capacitor (C
COMP1
) creates the
dominant pole. Due to the current-mode control
scheme, the output capacitor also creates a pole in the
system which is a function of the load resistance. As
the load resistance increases, the frequency of the out-
put capacitor
’
s pole decreases. However, the DC loop
gain increases with larger load resistance, so the unity-
gain bandwidth remains fixed. Additionally, the com-
pensation resistor and the output capacitor
’
s ESR both
generate zeros which must be canceled out by corre-
sponding poles. Therefore, in order to achieve stable
operation, use the following procedure to properly com-
pensate the system:
1) The crossover frequency (the frequency at which
unity gain occurs) must be less than 1/5th the
switching frequency:
2) Determine the series compensation capacitor
(C
COMP1
) required to set the desired crossover fre-
quency:
where the error amplifier
’
s transconductance (g
m
)
is 100μS (see
Electrical Characteristics
) and A
V(DC)
is the total DC loop gain defined above.
3) Before crossover occurs, the output capacitor and
the load resistor generate a second pole:
4) The series compensation resistor and capacitor
provide a zero which can be used to cancel the
second pole in order to ensure stability:
5) For most applications using electrolytic capacitors,
the output capacitor
’
s ESR forms a second zero
that occurs before crossover. Applications using
low-ESR capacitors (e.g., polymer, OS-CON) may
have ESR zeros that occur after crossover.
Therefore, verify the frequency of the output capaci-
tor
’
s ESR zero:
6) Finally, if the output capacitor
’
s ESR zero occurs
before crossover, add the parallel compensation
capacitor (C
COMP2
) to form a third pole to cancel
this second zero:
For example, the MAX1964
Standard Application
Circuit
shown in Figure 1 requires a 5V output that sup-
ports up to 2A. Using the above compensation guide-
lines, we can determine the proper component values:
First, select the crossover frequency to be 1/5th the
200kHz switching frequency.
Next, determine the total DC loop gain (A
V(DC)
) so
you can calculate the series compensation capaci-
tance (C
COMP1
). Since the applications circuit uses
the International Rectifier IRF7101 with an R
DS(ON)
of 100m
, the DC loop gain approximately equals
2480 and C
COMP1
must be approximately 490pF.
Select the closest standard capacitor value of
470pF.
Determine the location of the output pole
(f
POLE(OUT)
). With a 5V output supplying 2A and a
1000μF electrolytic capacitor, the output pole
occurs at 64Hz.
C
C
R
C
f
f
COMP
COMP
COMP COMP ZERO ESR
COMP POLE OUT
1
-
ZERO ESR
POLE OUT
2
1
1
2
1
≈
(
)
≈
(
)
π
(
)
(
)
(
)
(
)
-
f
C
ZERO ESR
OUT ESR
(
)
≈
1
2
π
R
C
COMP
COMP POLE OUT
1
≥
1
2
π
(
)
f
C
I
π
C
POLE OUT
OUT LOAD
LOAD MAX
OUT OUT
(
)
(
)
=
=
1
2
2
π
C
g A
2000
f
COMP
V DC
(
C
1
1
π
2
≥
)
f
f
C
SW
5
≤
A
I
I
V
V
V
R
)
A
V
R
)
V DC
(
PEAK
LOAD
REF LOAD VEA
OUT NOMINAL
(
DS ON
(
VCS
REF LOAD
OUT NOMINAL
(
DS ON
(
)
)
)
≈
≈
≈
×
400
I
V
V
R
)
A
PEAK
OUT REF VEA
OUT NOMINAL
(
DS ON
(
VCS
=
)
Tracking/Sequencing Triple/Quintuple
Power-Supply Controllers
20
______________________________________________________________________________________
相關PDF資料 |
PDF描述 |
|---|---|
| MAX1964TEEE | Tracking/Sequencing Triple/Quintuple Power-Supply Controllers |
| MAX1965TEEP | Tracking/Sequencing Triple/Quintuple Power-Supply Controllers |
| MAX1966 | Low-Cost Voltage-Mode PWM Step-Down Controllers |
| MAX1967EUB | Low-Cost Voltage-Mode PWM Step-Down Controllers |
| MAX1966-MAX1967 | Low-Cost Voltage-Mode PWM Step-Down Controllers |
相關代理商/技術參數 |
參數描述 |
|---|---|
| MAX1965TEEP | 功能描述:電流和電力監(jiān)控器、調節(jié)器 RoHS:否 制造商:STMicroelectronics 產品:Current Regulators 電源電壓-最大:48 V 電源電壓-最小:5.5 V 工作溫度范圍:- 40 C to + 150 C 安裝風格:SMD/SMT 封裝 / 箱體:HPSO-8 封裝:Reel |
| MAX1965TEEP-T | 功能描述:電流和電力監(jiān)控器、調節(jié)器 RoHS:否 制造商:STMicroelectronics 產品:Current Regulators 電源電壓-最大:48 V 電源電壓-最小:5.5 V 工作溫度范圍:- 40 C to + 150 C 安裝風格:SMD/SMT 封裝 / 箱體:HPSO-8 封裝:Reel |
| MAX1966ESA | 功能描述:電壓模式 PWM 控制器 RoHS:否 制造商:Texas Instruments 輸出端數量:1 拓撲結構:Buck 輸出電壓:34 V 輸出電流: 開關頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel |
| MAX1966ESA+ | 功能描述:電壓模式 PWM 控制器 Voltage-Mode PWM Step-Down RoHS:否 制造商:Texas Instruments 輸出端數量:1 拓撲結構:Buck 輸出電壓:34 V 輸出電流: 開關頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel |
| MAX1966ESA+T | 功能描述:電壓模式 PWM 控制器 Voltage-Mode PWM Step-Down RoHS:否 制造商:Texas Instruments 輸出端數量:1 拓撲結構:Buck 輸出電壓:34 V 輸出電流: 開關頻率: 工作電源電壓:4.5 V to 5.5 V 電源電流:600 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 封裝 / 箱體:WSON-8 封裝:Reel |
發(fā)布緊急采購，3分鐘左右您將得到回復。