- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄372193 > SP7653TR Wide Input Voltage Range, 1.3MHz,Buck Regulator PDF資料下載
參數(shù)資料
| 型號(hào)： | SP7653TR |
| 英文描述： | Wide Input Voltage Range, 1.3MHz,Buck Regulator |
| 中文描述： | 寬輸入電壓范圍，1.3MHz，降壓穩(wěn)壓器 |
| 文件頁(yè)數(shù)： | 6/12頁(yè) |
| 文件大?。?/td> | 207K |
| 代理商： | SP7653TR |
6
Date: 03/25/05
SP7653 Wide Input Voltage Range, 1.3MHz, Buck Regulator Copyright 2005 Sipex Corporation
THEORY OF OPERATION
pin externally. If a simple, single pole-single
zero response is desired, then compensation can
be as simple as an RC circuit to ground. If a more
complex compensation is required, then the
amplifier has enough bandwidth (45
°
at 4 MHz)
and enough gain (60dB) to run Type III compen-
sation schemes with adequate gain and phase
margins at cross over frequencies greater than
50kHz.
The common mode output of the error amplifier
is 0.9V to 2.2V. Therefore, the PWM voltage
ramp has been set between 1.1V and 2.2V to
ensure proper 0% to 100% duty cycle capability.
The voltage loop also includes two other very
important features. One is an asynchronous start
up mode. Basically, the synchronous rectifier
cannot turn on unless the high side switch has
attempted to turn on or the SS pin has exceeded
1.7V. This feature prevents the controller from
“dragging down” the output voltage during
startup or in fault modes. The second feature is
a 100% duty cycle timeout that ensures synchro-
nized refreshing of the Boost capacitor at very
high duty ratios. In the event that the high side
NFET is on for 20 continuous clock cycles, a
reset is given to the PWM flip flop half way
through the 21st cycle. This forces GL to rise for
the cycle, in turn refreshing the Boost capacitor.
The boost capacitor is used to generate a high
voltage drive supply for the high side switch,
which is 5V above V
IN
.
Power MOSFETs
The SP7653 contains a pair of integrated low
resistance N-channel switches designed for up
to 3A. Care should be taken to de-rate the output
current based on the thermal conditions in the
system such as ambient temperature, airflow
and heat sinking. Maximum output current could
be limited by thermal limitations of a particular
application by taking advantage of the inte-
grated-over-temperature protective scheme em-
ployed in the SP7653. The SP7653 incorporates
a built-in overtemperature protection to prevent
internal overheating.
GH
Voltage
GL
Voltage
V(VIN)
0V
-0V
-V(Diode) V
V(VIN)+V(VCC)
BST
Voltage
V(VCC)
TIME
SWN
Voltage
VBST
VSWN
V(VCC)
The SP7653 can be set to different output
voltages. The relationship in the following
formula is based on a voltage divider from the
output to the feedback pin V
, which is set to
an internal reference voltage of 0.80V.
Standard 1% metal film resistors of surface
mount size 0603 are recommended.
Vout = 0.80V ( R1 / R2 + 1 ) =>
R2 = R1 / [ ( Vout / 0.80V ) – 1 ]
Where R1 = 68.1K
and for Vout = 0.80V
setting, simply remove R2 from the board.
Furthermore, one could select the value of the
R1 and R2 combination to meet the exact
output voltage setting by restricting the
resistance range of R1 such that 50K
< R1
< 100K
for overall system loop stability.
Setting Output Voltages
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| SP7655 | Wide Input Voltage Range 8A, 300kHz, Buck Regulator |
| SP774BA | 12-Bit Sampling A/D Converters |
| SP774BB | 12-Bit Sampling A/D Converters |
| SP774BJ | 12-Bit Sampling A/D Converters |
| SP774BK | 12-Bit Sampling A/D Converters |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| SP7655 | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Wide Input Voltage Range 8A, 300kHz, Buck Regulator |
| SP7655_05 | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Evaluation Board Manual |
| SP7655_07 | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Wide Input Voltage Range, 8Amp 300kHz, Buck Regulator |
| SP7655EB | 功能描述:電源管理IC開發(fā)工具 Eval Board for SP7655 Series RoHS:否 制造商:Maxim Integrated 產(chǎn)品:Evaluation Kits 類型:Battery Management 工具用于評(píng)估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V |
| SP7655ER | 制造商:SIPEX 制造商全稱:Sipex Corporation 功能描述:Evaluation Board Manual |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。