- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄385449 > IRU3038 (International Rectifier) RES CHIP 383OHM 1/10 1% 100PP PDF資料下載
參數(shù)資料
| 型號： | IRU3038 |
| 廠商： | International Rectifier |
| 英文描述： | RES CHIP 383OHM 1/10 1% 100PP |
| 中文描述： | 同步PWM控制器終止電源應(yīng)用 |
| 文件頁數(shù)： | 5/18頁 |
| 文件大小： | 139K |
| 代理商： | IRU3038 |
IRU3038
5
Rev. 2.0
09/12/02
www.irf.com
APPLICATION INFORMATION
Design Example:
The following example is a typical application for IRU3038,
the schematic is Figure 11 on page 12.
V
IN
= 5V
V
OUT
= 2.5V
I
OUT
= 8A
V
OUT
= 100mV
f
S
= 200KHz
Output Voltage Programming
Output voltage is programmed by reference voltage and
external voltage divider. The Fb pin is the inverting input
of the error amplifier, which is referenced to the voltage
on non-inverting pin of error amplifier. For this applica-
tion, this pin (V
P
) is connected to reference voltage (V
REF
).
The output voltage is defined by using the following equa-
tion:
V
OUT
= V
P
×
1 +
---(1)
R
5
( )
When an external resistor divider is connected to the
output as shown in Figure 3.
Figure 3 - Typical application of the IRU3038 for
programming the output voltage.
Equation (1) can be rewritten as:
R
6
= R
5
×
( )
Choose R
5
= 1K
This will result to
R
6
= 1K
If the high value feedback resistors are used, the input
bias current of the Fb pin could cause a slight increase
in output voltage. The output voltage set point can be
more accurate by using precision resistor.
Soft-Start Programming
The soft-start timing can be programmed by selecting
the soft-start capacitance value. The start-up time of the
converter can be calculated by using:
t
START
= 75
×
Css (ms) ---(2)
Where C
SS
is the soft-start capacitor (
μ
F)
For a start-up time of 7.5ms, the soft-start capacitor will
be 0.1
μ
F. Choose a ceramic capacitor at 0.1
μ
F.
Shutdown
The converter can be shutdown by pulling the soft-start
pin below 0.5V. The control MOSFET turns off and the
synchronous MOSFET turns on during shutdown.
Boost Supply Vc
To drive the high-side switch it is necessary to supply a
gate voltage at least 4V greater than the bus voltage.
This is achieved by using a charge pump configuration
as shown in Figure 11. The capacitor is charged up to
approximately twice the bus voltage. A capacitor in the
range of 0.1
μ
F to 1
μ
F is generally adequate for most
applications. In application, when a separate voltage
source is available the boost circuit can be avoided as
shown in Figure 1.
Input Capacitor Selection
The input filter capacitor should be based on how much
ripple the supply can tolerate on the DC input line. The
ripple current generated during the on time of control
MOSFET should be provided by input capacitor. The RMS
value of this ripple is expressed by:
Where:
D is the Duty Cycle, D=V
OUT
/V
IN.
I
RMS
is the RMS value of the input capacitor current.
I
OUT
is the output current for each channel.
For higher efficiency, a low ESR capacitor is recom-
mended. Choose two Poscap from Sanyo 10TPB100ML
(10V, 100
μ
F, 55m
) with a maximum allowable ripple
current of 1.9A.
Fb
IRU3038
V
OUT
R
5
R
6
V
REF
V
P
For V
IN
=5V, I
OUT
=8A and D=0.5, the I
RMS
=4A
R
6
V
P
= V
REF
= 1.25V
- 1
V
OUT
V
P
I
RMS
= I
OUT
D
×
(1-D)
---(3)
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| IRU3038CF | RES CHP 3.83K 1/8W 1% |
| IRU3038CS | SYNCHRONOUS PWM CONTROLLER FOR TERMINATION POWER SUPPLY APPLICATIONS |
| IRU431AL | LOW -VOLTAGE ADJUSTABLE PRECISION SHUNT REGULATOR |
| IRU431ALCL3 | LOW -VOLTAGE ADJUSTABLE PRECISION SHUNT REGULATOR |
| IRU431ALCL5 | LOW -VOLTAGE ADJUSTABLE PRECISION SHUNT REGULATOR |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| IRU3038CF | 功能描述:IC REG CTRLR BUCK PWM VM TSSOP14 RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 標(biāo)準(zhǔn)包裝:2,000 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:50% 電源電壓:9 V ~ 10 V 降壓:無 升壓:是 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 85°C 封裝/外殼:8-TSSOP（0.173"，4.40mm 寬） 包裝:帶卷 (TR) |
| IRU3038CFTRPBF | 制造商:International Rectifier 功能描述:Voltage Mode PWM Controller 500mA 14-Pin TSSOP T/R |
| IRU3038CS | 功能描述:IC REG CTRLR BUCK PWM VM 14-SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 標(biāo)準(zhǔn)包裝:2,000 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:50% 電源電壓:9 V ~ 10 V 降壓:無 升壓:是 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 85°C 封裝/外殼:8-TSSOP（0.173"，4.40mm 寬） 包裝:帶卷 (TR) |
| IRU3038CSTR | 功能描述:IC REG CTRLR BUCK PWM VM 14-SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 特色產(chǎn)品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 標(biāo)準(zhǔn)包裝:1 系列:PowerWise® PWM 型:電壓模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:81% 電源電壓:4.5 V ~ 18 V 降壓:是 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-5°C ~ 125°C 封裝/外殼:32-WFQFN 裸露焊盤 包裝:Digi-Reel® 產(chǎn)品目錄頁面:1303 (CN2011-ZH PDF) 其它名稱:LM3754SQDKR |
| IRU3039 | 制造商:IRF 制造商全稱:International Rectifier 功能描述:SYNCHRONOUS PWM CONTROLLER WITH OVER CURRENT PROTECTION |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。