参数资料
| 型号： | ISL8130IAZ |
| 厂商： | Intersil |
| 文件页数： | 20/24页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BST FLYBK VM 20QSOP |
| 标准包装： | 58 |
| PWM 型： | 电压模式 |
| 输出数： | 1 |
| 频率 - 最大： | 1.4MHz |
| 占空比： | 100% |
| 电源电压： | 4.5 V ~ 5.5 V |
| 降压： | 是 |
| 升压： | 是 |
| 回扫： | 是 |
| 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： | 20-SSOP（0.154"，3.90mm 宽） |
| 包装： | 管件 |
ISL8130
The optimum MOSFET is usually that the conduction loss equals
the switching loss. The worst case for the MOSFET is at the
minimum VIN, when the inductor average current is the
maximum. The equations assume linear voltage-current
transitions and do not model power loss due to the
reverse-recovery of the Schottky diode.
INDUCTOR SELECTION
For a boost converter, the output ripple is not a strong function of
the boost inductor. The inductor is selected to meet the
efficiency, size and thermal requirement. Usually a smaller
inductor is preferred for cost, size and easy compensation. When
a small inductor is used, the inductor ripple current is large
Use ceramic capacitors for the high frequency decoupling and
bulk capacitors to supply the RMS current. Small ceramic
capacitors can be placed very close to the MOSFET and diode to
suppress the voltage induced in the parasitic circuit impedances.
CURRENT SENSING RESISTOR SELECTION
A small current sensing resistor is preferred for high efficiency
conversion. A too small R CS might not render an accurate
overcurrent protection threshold.
The current sensing resistor should be selected so that the
voltage across the current sensing resistor at OCP be greater
than 500mV for accurate OCP trip threshold (Equation 27).
R CS = ------------------------------------------------------------
incurring larger core loss. The ripple ration is usually from 30% to
50% (Equation 22).
500mV
I PKIND ? ( 1 + M arg in )
(EQ. 27)
L BST = ------------------------------------- DC ( 1 – DC )
V OUT
F SW Δ I R I OUT
2
(EQ. 22)
Where I PKIND is the maximum inductor peak current. It is
recommended to have 25% margin for load transient and
P RCS = R CS ( I PKIND ? ( 1 + M arg in ) )
(EQ. 28)
Where is Δ I R the desired ripple ratio. DC is the boost converter
duty cycle.
The DC inductor current is the maximum at the minimum V IN
(Equation 23).
variation.
Then the resistor should be sized to survive the maximum stress
at OCP (Equation 28).
2
I OUT ? V OUT
Δ i PP
I RMSIND = ----------------------------------- ? 1 + ----------------
V IN
12
2
(EQ. 23)
INPUT CAPACITOR SELECTION
The input current ripple for a boost converter is much smaller
The maximum peak inductor current occurs at the minimum
input (Equation 24).
than the output ripple. The input capacitor of the boost converter
is to filter out the inductor ripple current and to stabilize the
power supply and the boost converter.
I PKIND = I RMSIND + --- --------------------------- ? 1 – -------------------- ?
1 V INMIN ? V INMIN ?
2 L BST F SW ? V OUT ?
(EQ. 24)
The input capacitor should take the input RMS current
(Equation 29).
? V OUT ?
------ ? ? ------------------------------- ? DC ( 1 – DC ) ?
Select the inductor using Equation 22. with saturation current
higher than that calculated with Equation 24. Make sure the
I RMSIN =
1
12 ? L BST ? F SW ?
(EQ. 29)
inductor can handle the thermal stress.
OUTPUT CAPACITORS SELECTION
The important parameters for the bulk output capacitor(s) are
the voltage rating, the RMS current rating and output ripple. For
reliable operation, select bulk capacitors with voltage and
If the boost converter is powered by another DC/DC converter
with sufficient output capacitors, a small ceramic capacitor can
be used for the input capacitor.
Boost Converter Compensation
V OSC ? ( 1 – DC )
current ratings above the maximum output voltage, which should
be the OVP threshold and largest RMS current required by the
circuit. The capacitor voltage rating should be at least 1.25x
greater than the maximum output voltage and 1.5x is a
conservative guideline. The AC RMS output current varies with
MODULATOR BREAK FREQUENCY EQUATIONS
The modulator DC gain is (Equation 30):
V OUT
G DC = ---------------------------------------------
(EQ. 30)
the load and V IN . The total RMS current filtered by the output
capacitance is given by Equation 25:
V OSC is the internal oscillator output amplitude, which is 1.25V,
DC is the boost converter duty cycle.
I RMSOUT = I OUT ? ---------------- – 1
V OUT
V IN
(EQ. 25)
The Boost converter double pole is a function of the duty cycle,
inductor and output capacitor (Equation 31).
F LC = ----------------------------------------------
The worst case is at full load and minimum V IN . When the
maximum AC ripple current is as shown in Equation 26:
1 – DC
2 π ? ( L BST ? C O )
(EQ. 31)
I RMSOUT = I OUTMAX ? -------------------- – 1
V OUT
V INMIN
(EQ. 26)
The output capacitor ESR adds a zero to the loop gain
(Equation 32).
F ESR = ---------------------------------------------
20
1
2 π ? ( ESR ? C O )
(EQ. 32)
FN7954.3
October 5, 2012
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| ISL8130IAZ-T7A | 功能描述:电流型 PWM 控制器 PB-FREE SYNC BUCK PWM CONT. W/ 4.5V-28V INPUT,20LD QSOP, 250 RoHS:否 制造商:Texas Instruments 开关频率:27 KHz 上升时间: 下降时间: 工作电源电压:6 V to 15 V 工作电源电流:1.5 mA 输出端数量:1 最大工作温度:+ 105 C 安装风格:SMD/SMT 封装 / 箱体:TSSOP-14 |
| ISL8130IAZ-TK | 功能描述:IC REG CTRLR BST FLYBK VM 20QSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) |
| ISL8130IRZ | 功能描述:IC REG CTRLR BST FLYBK PWM 20QFN 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:75 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.3 V ~ 13.5 V 降压:是 升压:是 回扫:是 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:0°C ~ 70°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:管件 产品目录页面:1051 (CN2011-ZH PDF) 其它名称:296-2543-5 |
| ISL8130IRZ-T7A | 功能描述:电流型 PWM 控制器 Pb-Free W/Anneal SYNC BUCK PWM CONT. WITH 4.5V-28V INPUT,20 RoHS:否 制造商:Texas Instruments 开关频率:27 KHz 上升时间: 下降时间: 工作电源电压:6 V to 15 V 工作电源电流:1.5 mA 输出端数量:1 最大工作温度:+ 105 C 安装风格:SMD/SMT 封装 / 箱体:TSSOP-14 |
| ISL8130IRZ-TK | 功能描述:IC REG CTRLR BST FLYBK PWM 20QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 产品培训模块:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:275kHz 占空比:50% 电源电压:18 V ~ 110 V 降压:无 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:是 工作温度:-40°C ~ 85°C 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) |
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