参数资料
| 型号： | ISL6556BCR-T |
| 厂商： | Intersil |
| 文件页数： | 21/24页 |
| 文件大小： | 0K |
| 描述： | IC CTRLR MULTIPHASE VRM10 32-QFN |
| 标准包装： | 6,000 |
| 应用： | 控制器，Intel VR10X |
| 输入电压： | 3 V ~ 12 V |
| 输出数： | 4 |
| 输出电压： | 0.84 V ~ 1.6 V |
| 工作温度： | 0°C ~ 70°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 32-VFQFN 裸露焊盘 |
| 供应商设备封装： | 32-QFN 裸露焊盘（5x5） |
| 包装： | 带卷 (TR) |
ISL6556B
Input Supply Voltage Selection
The VCC input of the ISL6556B can be connected either
directly to a +5V supply or through a current limiting resistor to
a +12V supply. An integrated 5.8V shunt regulator maintains
the voltage on the VCC pin when a +12V supply is used. A
300 ? resistor is suggested for limiting the current into the
VCC pin to a worst-case maximum of approximately 25mA.
Switching Frequency
There are a number of variables to consider when choosing
the switching frequency, as there are considerable effects on
the upper-MOSFET loss calculation. These effects are
outlined in MOSFETs , and they establish the upper limit for
the switching frequency. The lower limit is established by the
requirement for fast transient response and small output-
voltage ripple as outlined in Output Filter Design . Choose the
lowest switching frequency that allows the regulator to meet
the transient-response requirements.
Switching frequency is determined by the selection of the
frequency-setting resistor, R T (see the figures labeled
Typical Application on pages 4 and 5). Figure 13 and
Equation 27 are provided to assist in selecting the correct
Select a bulk capacitor with a ripple current rating which will
minimize the total number of input capacitors required to
support the RMS current calculated. The voltage rating of
the capacitors should also be at least 1.25 times greater
than the maximum input voltage.
Figures 15 and 16 provide the same input RMS current
information for three and four phase designs respectively.
Use the same approach to selecting the bulk capacitor type
and number as described above.
Low capacitance, high-frequency ceramic capacitors are
needed in addition to the bulk capacitors to suppress leading
and falling edge voltage spikes. The result from the high
current slew rates produced by the upper MOSFETs turn on
and off. Select low ESL ceramic capacitors and place one as
close as possible to each upper MOSFET drain to minimize
board parasitic impedances and maximize suppression.
0.3
value for R T .
R T = 1.0203 ( 10 )
·
[ 10.6258- ( 1.03167 ) log ( f S ) ]
– 1200
(EQ. 27)
0.2
1000
0.1
I L,PP = 0
I L,PP = 0.5 I O
I L,PP = 0.75 I O
0
0
0.2
0.4
0.6
0.8
1.0
100
DUTY CYCLE (V O / V IN )
FIGURE 14. NORMALIZED INPUT-CAPACITOR RMS CURRENT
vs DUTY CYCLE FOR 2-PHASE CONVERTER
0.3
I L,PP = 0
I L,PP = 0.25 I O
I L,PP = 0.5 I O
I L,PP = 0.75 I O
10
10
100 1000
SWITCHING FREQUENCY (kHz)
10000
0.2
FIGURE 13. R T vs SWITCHING FREQUENCY
Input Capacitor Selection
The input capacitors are responsible for sourcing the ac
component of the input current flowing into the upper
MOSFETs. Their RMS current capacity must be sufficient to
handle the ac component of the current drawn by the upper
MOSFETs which is related to duty cycle and the number of
active phases.
For a two phase design, use Figure 14 to determine the
input-capacitor RMS current requirement given the duty
cycle, maximum sustained output current (I O ), and the ratio
of the per-phase peak-to-peak inductor current (I L,PP ) to I O .
21
0.1
0
0 0.2 0.4 0.6 0.8 1.0
DUTY CYCLE (V O / V IN )
FIGURE 15. NORMALIZED INPUT-CAPACITOR RMS CURRENT
vs DUTY CYCLE FOR 3-PHASE CONVERTER
FN9097.4
December 28, 2004
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相关代理商/技术参数 |
参数描述 |
|---|---|
| ISL6556BCRZ | 功能描述:IC CTRLR MULTIPHASE VRM10 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
| ISL6556BCRZA | 功能描述:IC CTRLR MULTIPHASE VRM10 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
| ISL6556BCRZA-T | 功能描述:IC CTRLR MULTIPHASE VRM10 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
| ISL6556BCRZ-T | 功能描述:IC CTRLR MULTIPHASE VRM10 32-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 专用型 系列:- 标准包装:43 系列:- 应用:控制器，Intel VR11 输入电压:5 V ~ 12 V 输出数:1 输出电压:0.5 V ~ 1.6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:48-VFQFN 裸露焊盘 供应商设备封装:48-QFN（7x7） 包装:管件 |
| ISL6557 WAF | 制造商:Intersil Corporation 功能描述: |
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