参数资料
型号: IR3622MTRPBF
厂商: International Rectifier
文件页数: 13/31页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM VM 32MLPQ
标准包装: 1
PWM 型: 电压模式
输出数: 2
频率 - 最大: 600kHz
占空比: 84%
电源电压: 7.5 V ~ 14.5 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 125°C
封装/外壳: 32-VFQFN 裸露焊盘
包装: 标准包装
其它名称: IR3622MTRPBFDKR
IR3622MPbF
Soft-Start (cont.)
3V
During power up, the converter output starts at
zero and thus the voltage at Fb is about 0V. An
internal voltage-controlled current source (64uA)
injects current into the Fb pin and generates a
voltage about 1.6V (64ux25K) across the
negative input of error amplifier, see figure 7.
This keeps the output of the error amplifier low.
The magnitude of this current is inversely
proportional to the voltage at the soft-start pin.
The 23uA current source starts to charge up the
external capacitor. In the mean time, the soft-
start voltage ramps up, the current flowing into
Fb pin starts to decrease linearly and so does the
voltage at the negative input of error amplifier.
When the soft-start voltage reaches about 1V,
the voltage at the negative input of the error
amplifier is approximately 0.8V.
As the soft-start capacitor voltage charges up,
the current flowing into the Fb pin keeps
decreasing.
The feedback voltage increases linearly as the
injecting current goes down. The injecting current
drops to zero when soft-start voltage is around
1.8V and the output voltage goes into steady
state. Figure 8 shows the theoretical operational
waveforms during soft-start.
The output start-up time is the time period when
soft-start capacitor voltage increases from 1V to
SS1/SD1
Seq
Fb1
VP1
SS2/SD2
Fb2
VP2
Track
64uA
POR
64uA
POR
I SS1 = 23uA
I hiccup1 = 3uA
E/A1
3V
I SS2 = 23uA
OCP2
I hiccup2 = 3uA
E/A2
OCP1
1.8V. The start-up time will be dependent on the
size of the external soft-start capacitor. The start-
up time can be estimated by:
Fig. 7: Soft-Start circuit for IR3622
23 μA ?
T start
C ss
= 1 . 8 V ? 1 V
Output of POR
3V
? 1.8V
For a given start up time, the soft-start capacitor
(nF) can be estimated as:
Soft-Start
Voltage
0V
? 1V
C SS ?
23 ( μ A ) * T start ( ms )
0 . 8 ( V )
- - - - ( 5 )
Current flowing
into Fb pin
64uA
0uA
For normal start up the Seq pin should be pulled
Voltage at negative input ? 1.6V
of Error Amp
0.8V
high (usually can be connected to Vout3).
Voltage at Fb pin
0V
0.8V
Fig. 8: Theoretical operation waveforms
during soft-start
www.irf.com
13
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IR3623MPBF 功能描述:IC REG CTRLR BUCK PWM VM 32MLPQ RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR)
IR3623MPBF_1 制造商:IRF 制造商全称:International Rectifier 功能描述:HIGH FREQUENCY 2-PHASE, SINGLE OR DUAL OUTPUT SYNCHRONOUS STEP DOWN CONTROLLER WITH OUTPUT TRACKING AND SEQUENCING
IR3623MTRPBF 功能描述:开关变换器、稳压器与控制器 HI FREQ 2-PHASE Single or Dual SYNCH RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel
IR3624MPBF 功能描述:IC REG CTRLR BUCK PWM VM 10-MLPD RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:4,000 系列:- PWM 型:电压模式 输出数:1 频率 - 最大:1.5MHz 占空比:66.7% 电源电压:4.75 V ~ 5.25 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:40-VFQFN 裸露焊盘 包装:带卷 (TR)
IR3624MTRPBF 功能描述:开关变换器、稳压器与控制器 HI FREQ SYNC PWM 600kHz 5 or 12V 0.6 RoHS:否 制造商:Texas Instruments 输出电压:1.2 V to 10 V 输出电流:300 mA 输出功率: 输入电压:3 V to 17 V 开关频率:1 MHz 工作温度范围: 安装风格:SMD/SMT 封装 / 箱体:WSON-8 封装:Reel