- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383156 > ISL6556ACRZ-T (INTERSIL CORP) PWM Controller with Wide Input Range 8-PDIP -40 to 85 PDF資料下載
參數(shù)資料
| 型號： | ISL6556ACRZ-T |
| 廠商： | INTERSIL CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | PWM Controller with Wide Input Range 8-PDIP -40 to 85 |
| 中文描述： | SWITCHING CONTROLLER, 1500 kHz SWITCHING FREQ-MAX, PQCC32 |
| 封裝： | 5 X 5 MM, ROHS COMPLIANT, PLASTIC, MO-220VHHD-2, QFN-32 |
| 文件頁數(shù)： | 10/24頁 |
| 文件大?。?/td> | 702K |
| 代理商： | ISL6556ACRZ-T |
10
OFSOUT (ISL6556ACR only)
OFSOUT is the output of the offset-current generating
circuit. It must be connected either to REF (recommended)
or FB to generate a dc offset.
OVP
Overvoltage protection pin. This pin pulls to VCC and is
latched when an overvoltage condition is detected. Connect
this pin to the gate of an SCR or MOSFET tied from V
IN
or
V
OUT
to ground to prevent damage to the load. This pin may
be pulled as high as 15V to ground with an external resistor.
However, it is only capable of pulling low when VCC is above
2V.
Operation
Multi-Phase Power Conversion
Microprocessor load current profiles have changed to the
point that the advantages of multi-phase power conversion
are impossible to ignore. The technical challenges
associated with producing a single-phase converter which is
both cost-effective and thermally viable have forced a
change to the cost-saving approach of multi-phase. The
ISL6556A controller helps in simplifying the implementation
by integrating vital functions and requiring minimal output
components. The block diagrams on pages 2 and 3 provide
top level views of multi-phase power conversion using the
ISL65556ACB and ISL6556ACR controllers.
Interleaving
The switching of each channel in a multi-phase converter is
timed to be symmetrically out of phase with each of the other
channels. In a 3-phase converter, each channel switches 1/3
cycle after the previous channel and 1/3 cycle before the
following channel. As a result, the three-phase converter has
a combined ripple frequency three times greater than the
ripple frequency of any one phase. In addition, the peak-to-
peak amplitude of the combined inductor currents is reduced
in proportion to the number of phases (Equations 1 and 2).
Increased ripple frequency and lower ripple amplitude mean
that the designer can use less per-channel inductance and
lower total output capacitance for any performance
specification.
Figure 1 illustrates the multiplicative effect on output ripple
frequency. The three channel currents (IL1, IL2, and IL3)
combine to form the AC ripple current and the DC load
current. The ripple component has three times the ripple
frequency of each individual channel current. Each PWM
pulse is terminated 1/3 of a cycle after the PWM pulse of the
previous phase. The peak-to-peak current for each phase is
about 7A, and the dc components of the inductor currents
combine to feed the load.
To understand the reduction of ripple current amplitude in the
multi-phase circuit, examine the equation representing an
individual channel’s peak-to-peak inductor current.
In Equation 1, V
IN
and V
OUT
are the input and output
voltages respectively, L is the single-channel inductor value,
and f
S
is the switching frequency.
The output capacitors conduct the ripple component of the
inductor current. In the case of multi-phase converters, the
capacitor current is the sum of the ripple currents from each
of the individual channels. Compare Equation 1 to the
expression for the peak-to-peak current after the summation
of N symmetrically phase-shifted inductor currents in
Equation 2. Peak-to-peak ripple current decreases by an
amount proportional to the number of channels. Output-
voltage ripple is a function of capacitance, capacitor
equivalent series resistance (ESR), and inductor ripple
current. Reducing the inductor ripple current allows the
designer to use fewer or less costly output capacitors.
Another benefit of interleaving is to reduce input ripple
current. Input capacitance is determined in part by the
maximum input ripple current. Multi-phase topologies can
improve overall system cost and size by lowering input ripple
current and allowing the designer to reduce the cost of input
capacitance. The example in Figure 2 illustrates input
currents from a three-phase converter combining to reduce
the total input ripple current.
The converter depicted in Figure 2 delivers 36A to a 1.5V
load from a 12V input. The RMS input capacitor current is
5.9A. Compare this to a single-phase converter also
stepping down 12V to 1.5V at 36A. The single-phase
FIGURE 1. PWM AND INDUCTOR-CURRENT WAVEFORMS
FOR 3-PHASE CONVERTER
1
μ
s/DIV
PWM2, 5V/DIV
PWM1, 5V/DIV
IL2, 7A/DIV
IL1, 7A/DIV
IL1 + IL2 + IL3, 7A/DIV
IL3, 7A/DIV
PWM3, 5V/DIV
I
PP
V
-
V
S
V
IN
(
---------------Lf
)
V
OUT
=
(EQ. 1)
I
L
PP
,
V
-
N V
S
V
IN
(
------------------Lf
)
V
OUT
=
(EQ. 2)
ISL6556A
相關PDF資料 |
PDF描述 |
|---|---|
| ISL6556ACB-T | Optimized Multi-Phase PWM Controller with 6-Bit DAC for VR10.X Application |
| ISL6556ACBZ-T | Optimized Multi-Phase PWM Controller with 6-Bit DAC for VR10.X Application |
| ISL6556BCRZ-T | Optimized Multi-Phase PWM Controller with 6-Bit DAC and Programmable Internal Temperature Compensation for VR10.X Application |
| ISL6556BCBZ | Optimized Multi-Phase PWM Controller with 6-Bit DAC and Programmable Internal Temperature Compensation for VR10.X Application |
| ISL6556BCR-T | Optimized Multi-Phase PWM Controller with 6-Bit DAC and Programmable Internal Temperature Compensation for VR10.X Application |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| ISL6556ACRZ-TR5208 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Intersil Corporation 功能描述: |
| ISL6556BCB | 功能描述:IC CTRLR MULTIPHASE VRM10 28SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 產(chǎn)品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,000 系列:- 應用:電源，ICERA E400，E450 輸入電壓:4.1 V ~ 5.5 V 輸出數(shù):10 輸出電壓:可編程 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:42-WFBGA，WLCSP 供應商設備封裝:42-WLP 包裝:帶卷 (TR) |
| ISL6556BCB-T | 功能描述:IC CTRLR MULTIPHASE VRM10 28SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 產(chǎn)品培訓模塊:Lead (SnPb) Finish for COTS Obsolescence Mitigation Program 標準包裝:2,000 系列:- 應用:電源，ICERA E400，E450 輸入電壓:4.1 V ~ 5.5 V 輸出數(shù):10 輸出電壓:可編程 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:42-WFBGA，WLCSP 供應商設備封裝:42-WLP 包裝:帶卷 (TR) |
| ISL6556BCBZ | 功能描述:電流型 PWM 控制器 VRM 10 0 MULTI-PHS CONTROLLER RoHS:否 制造商:Texas Instruments 開關頻率:27 KHz 上升時間: 下降時間: 工作電源電壓:6 V to 15 V 工作電源電流:1.5 mA 輸出端數(shù)量:1 最大工作溫度:+ 105 C 安裝風格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
| ISL6556BCBZ | 制造商:Intersil Corporation 功能描述:Pulse Width Modulation (PWM) Controller |
發(fā)布緊急采購，3分鐘左右您將得到回復。