參數(shù)資料
型號(hào): TOP245P
英文描述: Up to 290 W Extended power. design flexible.
中文描述: 高達(dá)290瓦的擴(kuò)展能力。設(shè)計(jì)靈活。
文件頁(yè)數(shù): 30/52頁(yè)
文件大?。?/td> 468K
代理商: TOP245P
TOP242-250
30
K
9/03
General Information & Table of Contents
SOURCE pins will act as an effective heat sink. On double
sided boards (Figure 49), top side and bottom side areas
connected with vias can be used to increase the effective heat
sinking area.
Design Ideas 4
specifications are not exceeded under worst case conditions.
The following minimum set of tests is strongly recommended:
DPA-SwitchDC-DC Seminar 8
1. Maximum drain voltage – Verify that peak V
does not
exceed 675 V at highest input voltage and maximum
overload output power. Maximum overload output power
occurs when the output is overloaded to a level just before
the power supply goes into auto-restart (loss of regulation).
LINE-SENSE or EXTERNAL CURRENT LIMIT pins. This
is because the SOURCE pin is also the controller ground
reference pin.
2. Maximum drain current – At maximum ambient
TOPSwitch-GXAC-DC Seminar 10
coupling. LINE-SENSE resistor (R1 in figures 47-49) should
be located close to the M or L pin to minimize the trace length
on the M or L pin side.
For designs where operating current is significantly lower than
the default current limit, it is recommended to use an externally
set current limit close to the operating peak current to reduce
peak flux density and peak power (see Figures 20 and 34). In
most applications, the tighter current limit tolerance, higher
switching frequency and soft-start features of
TOPSwitch-GX
contribute to a smaller transformer when compared to
TOPSwitch-II.
Standby Consumption
Frequency reduction can significantly reduce power loss at light
or no load, especially when a Zener clamp is used. For very
low secondary power consumption use a TL431 regulator for
feedback control. Alternately, switching losses can be
significantly reduced by changing from 132 kHz in normal
operation to 66 kHz under light load conditions.
TOPSwitch-GX
Layout Considerations
As
TOPSwitch-GX
has additional pins and operates at much
higher power levels compared to previous
TOPSwitch
families, the following guidelines should be carefully
followed.
Primary Side Connections
Use a single point (Kelvin) connection at the negative terminal
of the input filter capacitor for
TOPSwitch-GX
source pin and
bias winding return. This improves surge capabilities by
returning surge currents from the bias winding directly to the
input filter capacitor.
The CONTROL pin bypass capacitor should be located as
close as possible to the SOURCE and CONTROL pins and its
SOURCE connection trace should not be shared by the main
MOSFET switching currents. All SOURCE pin referenced
components connected to the MULTI-FUNCTION, LINE-
SENSE or EXTERNAL CURRENT LIMIT pins should also
be located closely between their respective pin and SOURCE.
Once again the SOURCE connection trace of these
components should not be shared by the main MOSFET
switching currents. It is very critical that SOURCE pin
switching currents are returned to the input capacitor negative
terminal through a seperate trace that is not shared by the
components connected to CONTROL, MULTI-FUNCTION,
Any traces to the M, L or X pins should be kept as short as
possible and away from the DRAIN trace to prevent noise
In addition to the 47
μ
F CONTROL pin capacitor, a high
frequency bypass capacitor in parallel may be used for better
noise immunity. The feedback optocoupler output should also
be located close to the CONTROL and SOURCE pins of
TOPSwitch-GX.
Y-Capacitor
The Y-capacitor should be connected close to the secondary
output return pin(s) and the positive primary DC input pin of
the transformer.
Heat Sinking
The tab of the Y package (TO-220) or F package (TO-262) is
internally electrically tied to the SOURCE pin. To avoid
circulating currents, a heat sink attached to the tab should not
be electrically tied to any primary ground/source nodes on the
PC board.
When using a P (DIP-8), G (SMD-8) or R (TO-263) package,
a copper area underneath the package connected to the
In addition, sufficient copper area should be provided at the
anode and cathode leads of the output diode(s) for heat
sinking.
In Figures 47, 48 and 49 a narrow trace is shown between the
output rectifier and output filter capacitor. This trace acts as a
thermal relief between the rectifier and filter capacitor to
prevent excessive heating of the capacitor.
Quick Design Checklist
As with any power supply design, all
TOPSwitch-GX
designs
should be verified on the bench to make sure that components
temperature, maximum input voltage and maximum output
load, verify drain current waveforms at start-up for any signs
of transformer saturation and excessive leading edge current
spikes.
TOPSwitch-GX
has a leading edge blanking time
of 220 ns to prevent premature termination of the on-cycle.
相關(guān)PDF資料
PDF描述
TOPD345-RX5 Optoelectronic
TOPD346-RXMS Optoelectronic
TOPD347-RXB Telecommunication IC
TOPD347-RXBS Optoelectronic
TOPD347-RXBT Optoelectronic
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
TOP245P- 制造商:POWERINT 制造商全稱:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP245P_1 制造商:POWERINT 制造商全稱:Power Integrations, Inc. 功能描述:Title 32W (47W peak) Multiple Output supply
TOP245PN 功能描述:交流/直流開關(guān)轉(zhuǎn)換器 22W 85-265 VAC 30 W 230 VAC RoHS:否 制造商:STMicroelectronics 輸出電壓:800 V 輸入/電源電壓(最大值):23.5 V 輸入/電源電壓(最小值):11.5 V 開關(guān)頻率:115 kHz 電源電流:1.6 mA 工作溫度范圍:- 40 C to + 150 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SSO-10 封裝:Reel
TOP245PN- 制造商:POWERINT 制造商全稱:Power Integrations, Inc. 功能描述:TOPSwitch-GX Family Extended Power, Design Flexible, EcoSmart, Integrated Off-line Switcher
TOP245PN0152 制造商:Power Integrations 功能描述: