- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384525 > ISL6539CA-T (INTERSIL CORP) Wide Input Range Dual PWM Controller with DDR Option PDF資料下載
參數(shù)資料
| 型號： | ISL6539CA-T |
| 廠商： | INTERSIL CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | Wide Input Range Dual PWM Controller with DDR Option |
| 中文描述： | DUAL SWITCHING CONTROLLER, 345 kHz SWITCHING FREQ-MAX, PDSO28 |
| 封裝： | PLASTIC, QSOP-28 |
| 文件頁數(shù)： | 12/20頁 |
| 文件大?。?/td> | 503K |
| 代理商： | ISL6539CA-T |
12
FN9144.4
June 6, 2005
over frequency at about 30kHz. With a given set of
parameters, including the MOSFET r
DSON
, current sense
resistor R
CS
, output LC filter, and feedback network, the
system loop gain can be accurately analyzed and modified
by the system designers based on the applications
requirements.
Gate Control Logic
The gate control logic translates generated PWM signals
into gate drive signals providing necessary amplification,
level shift, and shoot-through protection. It bears some
functions that help to optimize the IC performance over a
wide range of the operational conditions. As MOSFET
switching time can vary dramatically from type to type, and
with the input voltage, the gate control logic provides
adaptive dead time by monitoring real gate waveforms of
both the upper and the lower MOSFETs.
Dual-Step Conversion
The ISL6539 dual channel controller can be used either in
power systems with a single-stage power conversion or in
systems where some intermediate voltages are initially
established. The choice of the approach may be dictated by
the overall system design criteria, or the approach may be a
matter of voltages available to the system designer.
When the output voltage is regulated from low voltage such
as 5V, the feed-forward ramp may become too shallow,
creating the possibility of duty-factor jitter; this is particularly
relevant in a noisy environment. Noise susceptibility, when
operating from low level regulated power sources, can be
improved by connecting the VIN pin to ground, by which the
feed-forward ramp generator will be internally reconnected
from the VIN pin to the VCC pin, and the ramp slew rate will
be doubled.
Voltage Monitor and Protections
The converter output is monitored and protected against
extreme overload, short circuit, overvoltage, and
undervoltage conditions. A sustained overload on the output
sets the PGOOD low and latches off the offending channel of
the chip. The controller operation can be restored by cycling
the VCC voltage or toggling both enable (EN) pins to low to
clear the latch.
Power Good
In the soft-start process, the PGOOD is established after the
soft pin voltage is at 1.5V. In normal operation, the PGOOD
window is 100mV below the 0.9V and 135mV higher than
0.9V. The VSEN pin has to stay within this window for
PGOOD to be high. Since the VSEN pin is used for both
feedback and monitoring purposes, the output voltage
deviation can be coupled directly to the VSEN pin by the
capacitor in parallel with the voltage divider as shown in
Figure 4. In order to prevent false PGOOD drop, capacitors
need to parallel at the output to confine the voltage deviation
with severe load step transient. The PGOOD comparator has
a built-in 3μs filter. PGOOD is an open drain output.
Overcurrent Protection
In dual switcher application, both PWM controllers use the
lower MOSFETs on-resistance r
DSON,
to monitor the
current for protection against shorted outputs. The sensed
current from the ISEN pin is compared with a current set by
a resistor connected from the OCSET pin to ground:
where I
OC
is a desired overcurrent protection threshold and
R
CS
is the value of the current sense resistor connected to
the ISEN pin. The 8μA is the offset current added on top of
the sensed current from the ISEN pin for internal circuit
biasing.
If the lower MOSFET current exceeds the overcurrent
threshold, a pulse skipping circuit is activated. The upper
MOSFET will not be turned on as long as the sensed current
is higher than the threshold value, limiting the current
supplied by the DC voltage source. The current in the lower
MOSFET will be continuously monitored until it is lower than
the OC threshold value, then the following UGATE pulse will
be released and normal current sample resumes. This kind
of operation remains for eight clock cycles after the
overcurrent comparator was tripped for the first time. If after
the first eight clock cycles the current exceeds the
overcurrent threshold again, in a time interval of another
eight clock cycles, the overcurrent protection latches and
disables the offending channel. If the overcurrent condition
goes away during the first eight clock cycles, normal
operation is restored and the overcurrent circuit resets itself
at the end of sixteen clock cycles (See Figure 8).
FIGURE 7. THE BODE PLOT OF THE LC FILTER,
COMPENSATOR, CONTROL TO OUTPUT
VOLTAGE TRANSFER FUNCTION, AND SYSTEM
LOOP GAIN
0
10
20
30
40
50
60
100
110
3
FREQUENCY (Hz)
G
-10
-20
-30
-40
-50
-60
110
4
110
5
110
6
COMPENSATOR
LC FILTER
VO/VC
LOOP GAIN
R
SET
140
+
R
CS
)
--------------------------------------
8
μ
A
+
--------------------------------------------------------
=
ISL6539
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ISL6539CAZ | Wide Input Range Dual PWM Controller with DDR Option |
| ISL6539CAZ-T | Wide Input Range Dual PWM Controller with DDR Option |
| ISL6539IA | Wide Input Range Dual PWM Controller with DDR Option |
| ISL6539IA-T | Circular Connector; No. of Contacts:29; Series:D38999; Body Material:Metal; Connecting Termination:Crimp; Connector Shell Size:25; Circular Contact Gender:Socket; Circular Shell Style:Straight Plug; Insert Arrangement:25-29 |
| ISL6539IAZ | Wide Input Range Dual PWM Controller with DDR Option |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ISL6539CAZ | 功能描述:電流型 PWM 控制器 VER OF ISL6539CA RoHS:否 制造商:Texas Instruments 開關(guān)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(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
| ISL6539CAZ-T | 功能描述:電流型 PWM 控制器 VER OF ISL6539CA-T RoHS:否 制造商:Texas Instruments 開關(guān)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(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
| ISL6539EVAL1 | 功能描述:EVAL BOARD 1 FOR ISL6539 RoHS:否 類別:編程器，開發(fā)系統(tǒng) >> 評估板 - 線性穩(wěn)壓器 (LDO) 系列:* 產(chǎn)品變化通告:1Q2012 Discontinuation 30/Mar/2012 設(shè)計資源:NCP590MNDPTAGEVB Gerber Files 標準包裝:1 系列:- 每 IC 通道數(shù):2 - 雙 輸出電壓:1.8V，2.8V 電流 - 輸出:300mA 輸入電壓:2.1 ~ 5.5 V 穩(wěn)壓器類型:正，固定式 工作溫度:-40°C ~ 85°C 板類型:完全填充 已供物品:板 已用 IC / 零件:NCP590MNDP 其它名稱:NCP590MNDPTAGEVB-NDNCP590MNDPTAGEVBOS |
| ISL6539EVAL2 | 功能描述:EVAL BOARD 2 FOR ISL6539 RoHS:否 類別:編程器，開發(fā)系統(tǒng) >> 評估板 - 線性穩(wěn)壓器 (LDO) 系列:* 產(chǎn)品變化通告:1Q2012 Discontinuation 30/Mar/2012 設(shè)計資源:NCP590MNDPTAGEVB Gerber Files 標準包裝:1 系列:- 每 IC 通道數(shù):2 - 雙 輸出電壓:1.8V，2.8V 電流 - 輸出:300mA 輸入電壓:2.1 ~ 5.5 V 穩(wěn)壓器類型:正，固定式 工作溫度:-40°C ~ 85°C 板類型:完全填充 已供物品:板 已用 IC / 零件:NCP590MNDP 其它名稱:NCP590MNDPTAGEVB-NDNCP590MNDPTAGEVBOS |
| ISL6539IA | 功能描述:電流型 PWM 控制器 DUAL RoHS:否 制造商:Texas Instruments 開關(guān)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(fēng)格:SMD/SMT 封裝 / 箱體:TSSOP-14 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。