參數(shù)資料
型號： ISL6308CRZ-T
廠商： INTERSIL CORP
元件分類： 穩(wěn)壓器
英文描述： Quadruple 2-Input Exclusive-OR Gates 14-SOIC -40 to 85
中文描述： SWITCHING CONTROLLER, 1500 kHz SWITCHING FREQ-MAX, PQCC40
封裝： 6 X 6 MM, ROHS COMPLIANT, PLASTIC, MO-220VJJD-1, QFN-40
文件頁數(shù)： 20/27頁
文件大?。?/td> 765K
代理商： ISL6308CRZ-T
20
FN9208.2
October 19, 2005
dissipating their heat so that the affected channels run hotter
than desired, choose new, smaller values of R
ISEN
for the
affected phases (see the section entitled Channel Current
Balance). Choose R
ISEN,2
in proportion to the desired
decrease in temperature rise in order to cause proportionally
less current to flow in the hotter phase.
In Equation 24, make sure that
T
2
is the desired
temperature rise above the ambient temperature, and
T
1
is
the measured temperature rise above the ambient
temperature. While a single adjustment according to
Equation 24 is usually sufficient, it may occasionally be
necessary to adjust R
ISEN
two or more times to achieve
optimal thermal balance between all channels.
Load Line Regulation Component Selection (DCR
Current Sensing)
For accurate load line regulation, the ISL6308 senses the
total output current by detecting the voltage across the
output inductor DCR of each channel (As described in the
Load Line Regulation
section). As Figure 7 illustrates, an
R-C network is required to accurately sense the inductor
DCR voltage and convert this information into a droop
voltage, which is proportional to the total output current.
Choosing the components for this current sense network is a
two step process. First, R
COMP
and C
COMP
must be
chosen so that the time constant of this R
COMP
-C
COMP
network matches the time constant of the inductor L/DCR.
Then the resistor R
S
must be chosen to set the current
sense network gain, obtaining the desired full load droop
voltage. Follow the steps below to choose the component
values for this R-C network.
1. Choose an arbitrary value for C
COMP
. The recommended
value is 0.01μF.
2. Plug the inductor L and DCR component values, and the
values for C
COMP
chosen in steps 1, into Equation 25 to
calculate the value for R
COMP
.
3. Use the new value for R
COMP
obtained from Equation 25,
as well as the desired full load current, I
FL
, full load droop
voltage, V
DROOP
, and inductor DCR in Equation 26 to
calculate the value for R
S
.
I
DROOP
Due to errors in the inductance or DCR it may be necessary
to adjust the value of R
COMP
to match the time constants
correctly. The effects of time constant mismatch can be seen
in the form of droop overshoot or undershoot during the
initial load transient spike, as shown in Figure 18. Follow the
steps below to ensure the R-C and inductor L/DCR time
constants are matched accurately.
1. Capture a transient event with the oscilloscope set to
about L/DCR/2 (sec/div). For example, with L = 1
μ
H and
DCR = 1m
, set the oscilloscope to 500
μ
s/div.
2. Record
V1 and
V2 as shown in Figure 18.
3. Select a new value, R
COMP,2
, for the time constant
resistor based on the original value, R
COMP,1
, using the
following equation.
V
2
4. Replace R
COMP
with the new value and check to see that
the error is corrected. Repeat the procedure if necessary.
After choosing a new value for R
COMP
, it will most likely be
necessary to adjust the value of R
S
to obtain the desired full
load droop voltage. Use Equation 26 to obtain the new value
for R
S
.
Compensation
The two opposing goals of compensating the voltage
regulator are stability and speed. Depending on whether the
regulator employs the optional load-line regulation as
described in “
Load-Line Regulation
”, there are two distinct
methods for achieving these goals.
Compensating the Load-Line Regulated Converter
The load-line regulated converter behaves in a similar
manner to a peak current mode controller because the two
poles at the output filter L-C resonant frequency split with the
introduction of current information into the control loop. The
final location of these poles is determined by the system
function, the gain of the current signal, and the value of the
compensation components, R
2
and C
1
.
R
ISEN 2
R
ISEN
T
2
T
1
----------
=
(EQ. 24)
R
COMP
COMP
---------------------------------------
=
(EQ. 25)
R
S
------------------------
R
COMP
DCR
=
(EQ. 26)
R
COMP 2
R
COMP 1
1
----------
=
(EQ. 27)
FIGURE 18. TIME CONSTANT MISMATCH BEHAVIOR
V
1
V
OUT
I
TRAN
V
2
I
ISL6308
相關(guān)PDF資料
PDF描述
ISL6308IRZ-T Three-Phase Buck PWM Controller with High Current Integrated MOSFET Drivers
ISL6315 Two-Phase Multiphase Buck PWM Controller with Integrated MOSFET Drivers(帶集成MOSFET驅(qū)動器的雙相降壓PWM控制器)
ISL6316 Quadruple 2-Input Exclusive-OR Gates 14-SOIC -40 to 85
ISL6316IRZ MINIATURE TOGGLE SWITCH
ISL6316CRZ Enhanced 4-Phase PWM Controller with 6-Bit VID Code Capable of Precision RDS(ON) or DCR Differential Current Sensing for VR10 Application
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ISL6308CRZ-TR5374 制造商:Intersil Corporation 功能描述:ISL6308CRZ W/ 24HR BURN-IN - Tape and Reel 制造商:Intersil Corporation 功能描述:IC CTRLR PWM 3PHASE BUCK 40-QFN 制造商:Intersil 功能描述:ISL6308CRZ W/24HRU RN-IN
ISL6308CRZ-TR5453 制造商:Intersil Corporation 功能描述:STD. ISL6308CRZ-T W/GOLD BOND WIRE ONLY - Tape and Reel
ISL6308EVAL1Z 制造商:Intersil Corporation 功能描述:ISL6308 EVALUATION BOARD 1 - ROHS COMPLIANT - QFN - Bulk
ISL6308IRZ 功能描述:電壓模式 PWM 控制器 DAC-LESS MULTI-PHS PWM CNTRLR W/3-DRVRS RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)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
ISL6308IRZ-T 功能描述:電壓模式 PWM 控制器 DAC-LESS MULTI-PHS PWM CNTRLR W/3-DRVRS RoHS:否 制造商:Texas Instruments 輸出端數(shù)量:1 拓?fù)浣Y(jié)構(gòu):Buck 輸出電壓:34 V 輸出電流: 開關(guān)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(fù)。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*