- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄44988 > LTC1530IS8-2.5#PBF (LINEAR TECHNOLOGY CORP) SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO8 PDF資料下載
參數(shù)資料
| 型號： | LTC1530IS8-2.5#PBF |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封裝： | 0.150 INCH, PLASTIC, SO-8 |
| 文件頁數(shù)： | 24/24頁 |
| 文件大?。?/td> | 301K |
| 代理商： | LTC1530IS8-2.5#PBF |
9
LTC1530
1530fa
Typically, thermal shutdown is activated if the LTC1530’s
junction temperature exceeds 150
°C. G1 and G2 resume
switching when the junction temperature drops below
100
°C.
Soft-Start and Current Limit
Unlike other PWM parts, the LTC1530 includes an on-chip
soft-start capacitor that is used during start-up and cur-
rent limit operation. On power-up, an internal 4
A pull-up
at COMP brings the LTC1530 out of shutdown mode. An
internal current source then charges the internal CSS
capacitor. The COMP pin is clamped to one VGS above the
voltage on CSS during start-up. This prevents the error
amplifier from forcing the loop to maximum duty cycle.
The LTC1530 operates at low duty cycle as the COMP pin
voltage increases above about 2.4V. The slew rate of the
soft-start capacitor is typically 0.4V/ms. As the voltage on
CSS continues to increase, MSS eventually turns off and the
error amplifier regulates the output. The MIN comparator
is disabled if soft-start is active to prevent an override of
the soft-start function.
The LTC1530 includes another feedback loop to control
operation in current limit. Before each falling edge of G1,
the current comparator, CC, samples and holds the volt-
age drop across external MOSFET Q1 with the LTC1530’s
IFB pin. CC compares the voltage at IFB to the voltage at the
IMAX pin. As peak current rises, the voltage across the
RDS(ON) of Q1 increases. If the voltage at IFB drops below
IMAX, indicating that Q1’s drain current has exceeded the
maximum desired level, CC pulls current out of CSS. Duty
cycle decreases and the output current is controlled. The
CC comparator pulls current out of CSS in proportion to the
voltage difference between IFB and IMAX. Under minor
overload conditions, the voltage at CSS falls gradually,
creating a time delay before current limit activates. Very
short, mild overloads may not affect the output voltage at
all. Significant overload conditions allow the voltage on
CSS to reach a steady state and the output remains at a
reduced voltage until the overload is removed. Serious
overloads generate a large overdrive and allow CC to pull
the CSS voltage down quickly, thus preventing damage to
the external components.
By using the RDS(ON) of Q1 to measure output current, the
current limit circuit eliminates the sense resistor that
would otherwise be required. This minimizes the number
of components in the high current power path. The current
limit circuitry is not designed to be highly accurate. It is
primarily meant to prevent damage to the power supply
circuitry during fault conditions. The exact current level
where current limiting takes effect will vary from unit to
unit as the RDS(ON) of Q1 varies.
Figure 5a illustrates the basic connections for the current
limit circuitry. For a given current limit level, the external
resistor from IMAX to VIN is determined by:
LTC1530
+
CIN
COUT
VOUT
1530 F05
VIN
LO
20
IFB
G1
Q1
Q2
G2
IMAX
RIMAX
200
A
+
–
CC
Maximum load current
I
Inductor ripple current
=
V
f
oscillator frequency = 300kHz
L
value
R
n-r
tance of Q1 at I
200 A sink current
RIPPLE
IN
OSC
O
DS(ON)Q1
LMAX
R
IR
I
where
II
I
VV
LV
f
LTC
Inductor
O
esis
I
IMAX
LMAX
DS ON Q
IMAX
LMAX
LOAD
RIPPLE
LOAD
OUT
OIN
OSC
IMAX
= ()
=+
=
()( )
()( )( )
=
()
,
1
2
1530
Figure 5a. Current Limit Setting (Use Kelvin-Sense
Connections Directly at the Drain and Source of Q1)
APPLICATIO S I FOR ATIO
WU
UU
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC1530CS8-2.8#TR | SWITCHING CONTROLLER, 350 kHz SWITCHING FREQ-MAX, PDSO8 |
| LTC1628IG#PBF | 3 A SWITCHING CONTROLLER, 310 kHz SWITCHING FREQ-MAX, PDSO28 |
| LTC1628IG-SYNC#TR | 3 A SWITCHING CONTROLLER, 360 kHz SWITCHING FREQ-MAX, PDSO28 |
| LTC1643HCGN#PBF | 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO16 |
| LTC1643LCGN#TR | 4-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO16 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC1530IS8-3.3 | 功能描述:IC SW REG CNTRLR SYNC 3.3V 8SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標準包裝:43 系列:- 應用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應商設備封裝:48-QFN（7x7） 包裝:管件 |
| LTC1530IS8-3.3#PBF | 功能描述:IC SW REG CNTRLR SYNC 3.3V 8SOIC RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標準包裝:43 系列:- 應用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應商設備封裝:48-QFN（7x7） 包裝:管件 |
| LTC1530IS8-3.3#TR | 功能描述:IC SW REG CTRLR SYNC HIPWR 8SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標準包裝:43 系列:- 應用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應商設備封裝:48-QFN（7x7） 包裝:管件 |
| LTC1530IS8-3.3#TRPBF | 功能描述:IC SW REG CNTRLR SYNC 3.3V 8SOIC RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標準包裝:43 系列:- 應用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應商設備封裝:48-QFN（7x7） 包裝:管件 |
| LTC1530IS8PBF | 制造商:Linear Technology 功能描述:DC-DC Controller Sync Buck 3.5-7V SOIC8 |
發(fā)布緊急采購，3分鐘左右您將得到回復。