參數(shù)資料
型號(hào): EL7564CREZ-T13
廠商: INTERSIL CORP
元件分類: 穩(wěn)壓器
英文描述: Monolithic 4 Amp DC/DC Step-Down Regulator
中文描述: 5 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO28
封裝: ROHS COMPLIANT, MO-153, HTSSOP-28
文件頁數(shù): 15/17頁
文件大?。?/td> 644K
代理商: EL7564CREZ-T13
15
FN7297.3
May 9, 2005
4. Start-up Delay
A capacitor can be added to the EN pin to delay the
converter start-up (Figure 26) by utilizing the pull-up current.
The delay time is approximately:
Thermal Management
The EL7564CM utilizes “fused lead” packaging technology in
conjunction with the system board layout to achieve a lower
thermal resistance than typically found in standard SO20
packages. By fusing (or connecting) multiple external leads
to the die substrate within the package, a very conductive
heat path is created to the outside of the package. This
conductive heat path MUST then be connected to a heat
sinking area on the PCB in order to dissipate heat out and
away from the device. The conductive paths for the
EL7564CM package are the fused leads: # 6, 7, 11, 12, and
13. If a sufficient amount of PCB metal area is connected to
the fused package leads, a junction-to-ambient resistance of
43°C/W can be achieved (compared to 85°C/W for a
standard SO20 package). The general relationship between
PCB heat-sinking metal area and the thermal resistance for
this package is shown in the Performance Curves section of
this data sheet. It can be readily seen that the thermal
resistance for this package approaches an asymptotic value
of approximately 43°C/W without any airflow, and 33°C/W
with 100 LFPM airflow. Additional information can be found
in Application Note #8 (Measuring the Thermal Resistance
of Power Surface-Mount Packages). For a thermal shutdown
die junction temperature of 135°C, and power dissipation of
1.5W, the ambient temperature can be as high as 70°C
without airflow. With 100 LFPM airflow, the ambient
temperature can be extended to 85°C.
The EL7564CRE utilizes the 28-pin HTSSOP package. The
majority of heat is dissipated through the heat pad exposed
at the bottom of the package. Therefore, the heat pad needs
to be soldered to the PCB. The thermal resistance for this
package is as low as 29°C/W, better than that of SO20.
Typical performance is shown in the curves section. The
actual junction temperature can be measured at V
TJ
pin.
Since the thermal performance of the IC is heavily
dependent on the board layout, the system designer should
exercise care during the design phase to ensure that the IC
will operate under the worst-case environmental conditions.
Layout Considerations
The layout is very important for the converter to function
properly. Power Ground (
) and Signal Ground (
be separated to ensure that the high pulse current in the
Power Ground never interferes with the sensitive signals
connected to Signal Ground. They should only be connected
at one point (normally at the negative side of either the input
or output capacitor.)
) should
The trace connected to the FB pin is the most sensitive
trace. It needs to be as short as possible and in a “quiet”
place, preferably with the PGND or SGND traces
surrounding it.
In addition, the bypass capacitor connected to the V
DD
pin
needs to be as close to the pin as possible.
The heat of the chip is mainly dissipated through the PGND
pins for the CM package, and through the heat pad at the
bottom for the CRE package. Maximizing the copper area
around these PGND pins or the heat pad is preferable. In
addition, a solid ground plane is always helpful for the EMI
performance.
The demo board is a good example of layout based on these
principles. Please refer to the EL7564 Application Brief for
the layout.
t
d
ms
(
)
1200
C
μ
F
(
)
×
=
FIGURE 28. START-UP DELAY
1
2
15
14
13
12
6
7
8
11
10
9
20
19
EL7564
-
+
V
OUT
STP
STN
C
TIME
V
O
V
IN
t
d
EL7564
相關(guān)PDF資料
PDF描述
EL7564CREZ-T7 Monolithic 4 Amp DC/DC Step-Down Regulator
EL7564CM CLB Strip Light 332mm Red CE RoHS; Mounting Style: Horizontal/Vertical Mount; Functions: Continuous light; Light Type: LED; Rated Voltage: 24V DC; Style: Strip Light; Color: Red; Diameter: 332mm long; Applicable Model: CLB
EL7564CM-T13 CLE Series, Standard angle, Smoked lens; Functions: Continuous light; Light Type: LED; Rated Voltage: 24V DC; Style: Work light; Diameter: 71; Applicable Model: CLE
EL7564CMZ CLE Series, Narrower angle, Clear lens; Functions: Continuous light; Light Type: LED; Rated Voltage: 24V DC; Style: Work light; Diameter: 71; Applicable Model: CLE
EL7566AIREZ Monolithic 6 Amp DC-DC Step-Down Regulator
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
EL7564CREZ-T7 功能描述:直流/直流開關(guān)調(diào)節(jié)器 EL7564CREZ MONO 4 AMP STP DWN SWITCH RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
EL7566 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Monolithic 6 Amp DC-DC Step-Down Regulator
EL7566_06 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:Monolithic 6A DC/DC Step-Down Regulator
EL7566AIREZ 功能描述:直流/直流開關(guān)調(diào)節(jié)器 EL7566AIREZ MONOLITH 8 AMP DC:DC STP-DNGT RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5
EL7566AIREZ-T13 功能描述:直流/直流開關(guān)調(diào)節(jié)器 EL7566AIREZ MONOLITH 6 AMP DC:DC STP-DNGT RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5