- 您现在的位置：买卖IC网 > PDF目录14440 > LM2596TVADJG (ON Semiconductor)IC REG BUCK ADJ 3A TO220-5 PDF资料下载
参数资料
| 型号： | LM2596TVADJG |
| 厂商： | ON Semiconductor |
| 文件页数： | 16/25页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK ADJ 3A TO220-5 |
| 标准包装： | 50 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 1.23 V ~ 37 V |
| 输入电压： | 4.5 V ~ 40 V |
| PWM 型： | 电压模式 |
| 频率 - 开关： | 150kHz |
| 电流 - 输出： | 3A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 通孔 |
| 封装/外壳： | TO-220-5 成形引线 |
| 包装： | 管件 |
| 供应商设备封装： | TO-220-5 |
| 其它名称： | LM2596TVADJG-ND LM2596TVADJGOS |
LM2596
interference between two or more of the regulator circuits,
especially at high currents due to mutual coupling. A toroid,
pot core or E ? core (closed magnetic structure) should be
used in such applications.
Do Not Operate an Inductor Beyond its
Maximum Rated Current
Exceeding an inductor ’s maximum current rating may
cause the inductor to overheat because of the copper wire
losses, or the core may saturate. Core saturation occurs when
the flux density is too high and consequently the cross
sectional area of the core can no longer support additional
lines of magnetic flux.
This causes the permeability of the core to drop, the
inductance value decreases rapidly and the inductor begins
to look mainly resistive. It has only the DC resistance of the
winding. This can cause the switch current to rise very
rapidly and force the LM2596 internal switch into
cycle ? by ? cycle current limit, thus reducing the DC output
load current. This can also result in overheating of the
inductor and/or the LM2596. Different inductor types have
different saturation characteristics, and this should be kept
in mind when selecting an inductor.
0.4 A
Inductor
Current
Waveform
0A
0.4 A
Power
Switch
Current
Waveform
0A
HORIZONTAL TIME BASE: 2.0 m s/DIV
Figure 20. Discontinuous Mode Switching Current
Waveforms
GENERAL RECOMMENDATIONS
Output
Voltage
Output Voltage Ripple and Transients
Source of the Output Ripple
Since the LM2596 is a switch mode power supply
regulator, its output voltage, if left unfiltered, will contain a
sawtooth ripple voltage at the switching frequency. The
output ripple voltage value ranges from 0.5% to 3% of the
output voltage. It is caused mainly by the inductor sawtooth
ripple current multiplied by the ESR of the output capacitor.
Short Voltage Spikes and How to Reduce Them
The regulator output voltage may also contain short
voltage spikes at the peaks of the sawtooth waveform (see
Figure 21). These voltage spikes are present because of the
fast switching action of the output switch, and the parasitic
inductance of the output filter capacitor. There are some
other important factors such as wiring inductance, stray
capacitance, as well as the scope probe used to evaluate these
transients, all these contribute to the amplitude of these
spikes. To minimize these voltage spikes, low inductance
capacitors should be used, and their lead lengths must be
kept short. The importance of quality printed circuit board
layout design should also be highlighted.
Voltage spikes
caused by
switching action
Filtered of the output
switch and the
parasitic
inductance of the
output capacitor
Unfiltered
Output
Voltage
HORIZONTAL TIME BASE: 5.0 m s/DIV
Figure 21. Output Ripple Voltage Waveforms
Minimizing the Output Ripple
In order to minimize the output ripple voltage it is possible
to enlarge the inductance value of the inductor L1 and/or to
use a larger value output capacitor. There is also another way
to smooth the output by means of an additional LC filter (20
m H, 100 m F), that can be added to the output (see Figure 30)
to further reduce the amount of output ripple and transients.
With such a filter it is possible to reduce the output ripple
voltage transients 10 times or more. Figure 21 shows the
difference between filtered and unfiltered output waveforms
of the regulator shown in Figure 30.
The lower waveform is from the normal unfiltered output
of the converter, while the upper waveform shows the output
ripple voltage filtered by an additional LC filter.
Heatsinking and Thermal Considerations
The Through ? Hole Package TO ? 220
The LM2596 is available in two packages, a 5 ? pin
TO ? 220(T, TV) and a 5 ? pin surface mount D 2 PAK(D2T).
Although the TO ? 220(T) package needs a heatsink under
most conditions, there are some applications that require no
heatsink to keep the LM2596 junction temperature within
the allowed operating range. Higher ambient temperatures
require some heat sinking, either to the printed circuit (PC)
board or an external heatsink.
The Surface Mount Package D 2 PAK and its
Heatsinking
The other type of package, the surface mount D 2 PAK, is
designed to be soldered to the copper on the PC board. The
copper and the board are the heatsink for this package and
the other heat producing components, such as the catch
diode and inductor. The PC board copper area that the
package is soldered to should be at least 0.4 in 2 (or 260 mm 2 )
and ideally should have 2 or more square inches (1300 mm 2 )
of 0.0028 inch copper. Additional increases of copper area
beyond approximately 6.0 in 2 (4000 mm 2 ) will not improve
http://onsemi.com
16
相关PDF资料 |
PDF描述 |
|---|---|
| LQG15HN18NJ02D | INDUCTOR 18NH 300MA 0402 |
| LQG15HN15NJ02D | INDUCTOR 15NH 300MA 0402 |
| LM2574DW-ADJR2G | IC REG BUCK ADJ 0.5A 16SOICW |
| LM2574N-3.3G | IC REG BUCK 3.3V 0.5A 8DIP |
| LQG15HN12NJ02D | INDUCTOR 12NH 300MA 0402 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LM2597HVM-12 | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| LM2597HVM-12/NOPB | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| LM2597HVM-12/NOPB | 制造商:Texas Instruments 功能描述:DC/DC Converter IC |
| LM2597HVM-3.3 | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
| LM2597HVM-3.3/NOPB | 功能描述:直流/直流开关转换器 RoHS:否 制造商:STMicroelectronics 最大输入电压:4.5 V 开关频率:1.5 MHz 输出电压:4.6 V 输出电流:250 mA 输出端数量:2 最大工作温度:+ 85 C 安装风格:SMD/SMT |
发布紧急采购，3分钟左右您将得到回复。